Electrifying my '85 635CSi Euro

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Electrifying my '85 635CSi Euro

Post by mdkohler »

Hi Everyone,
I recently purchased a beautiful 1985 635CSi Euro from forum poster PantherCity.

My goal is to convert this classic to electric to use as my daily commuter. As far as I know, this will be the first/only electric E24 in the world. I already have the batteries and have begun ordering various electrical components such as the motor, controller, dc-dc converter, electric A/C compressor, etc. This means that when all of the parts finally arrive (some are on back order), I will have the gas components removed from the car that I no longer need, which some of you may be interested in.

These items will be made available for sale, so please let me know if you need them:
M30 Engine, Euro Spec (higher compression, higher HP), no oil or vacuum leaks (sold)
Complete exhaust system (sold, except for catalytic converter which is still available)
Fuel tank, fuel pump, fuel level sending unit, gas cap (sold)
A/C compressor ($75)
Radiator (make offer)
5 new Oil Filters
Oil cooler/radiator (sold)

The previous owner spent the last five years fixing it up so that there are no leaks of any kind and it runs like a top.
He also provided me with a lot of other items and spare parts that I have on ebay if you are interested to buy now.

https://www.ebay.com/sch/marckohler/m.h ... 7675.l2562

As I begin to receive components for the conversion, I will update this thread.

The details of the electrical conversion include:
170kW/227hp drivetrain (two 85kW AC motors), 309 lb-ft/440 Nm from 0-3600 rpm
27kWh of lithium ion batteries
6kW charger

Depending on how my finances go, I may have to do the conversion in two stages, first with one motor, then add the other at a later time.
For now, I've just been driving it and enjoying it.

Thanks for reading,
Last edited by mdkohler on Tue Oct 27, 2020 1:57 am, edited 4 times in total.
Marc
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Re: Electrifying my '85 635CSi Euro

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Here is a picture the day I picked it up.
Pure Joy
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Last edited by mdkohler on Sat Nov 23, 2019 1:26 am, edited 1 time in total.
Marc
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Re: Electrifying my '85 635CSi Euro

Post by olympia57 »

Mmmm. :-k
Speaking personally ,I commend your desire to save the planet from we that ( allegedly) pollute most ...
The technical hurdles you face are challenging but a credit to you for taking them on.
However , I can't help feeling your project is not dissimilar to ripping the heart out of one's favourite pet Labrador and replacing it with a windscreen washer motor , it'll do the same job but with no soul.
You must keep us posted and show us the final thing.
Don
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Re: Electrifying my '85 635CSi Euro

Post by 86_6series »

Why would you take the essence of the 6 series character and change to an unexciting, boring, down right head scratching conversion.

It's taking the life out of a great car. If your going to go from wonderful enjoyment to boring why not convert a classic Pinto.

Then the looks of the car would compliment the conversion.
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Hi Don,
I understand where you are coming from. But driving electric is not always about saving the planet. True, I have solar panels on my garage that will charge my car emissions free (at no additional cost to me), and I can charge at work (again for "free"), but driving electric also has many other advantages that mean a lot to me.

1) I hate going to the gas station. I hate the expense, the smell, the (lack of) cleanliness, etc. of the experience. Yes, I have done it for 35 years, but it has not gotten any more enjoyable over that time. With electric, I start with a full tank every time I get in the car.
2) As for a classic car or favorite pet, our love for them causes us to spend much money and time (either at the local classic repair shop or vet) keeping them alive. But I see the electrification as an opportunity to drive the car another decade without having to constantly invest time in fixing leaks or seals or any of the many things that a 35 yr old gas motor needs to keep running.
3) Yes, phase 1 with only one electric motor will lower it's performance compared to original (phase 2 with two motors would exceed the original engine's specs). But for my needs, it is fine, as my commute is 25 miles long and it takes me an hour to get there because of traffic. So you can see I won't be missing the additional hp, only the fumes and possible overheating issues of sitting in stop and go traffic.
4) For soul, once you drive electric, you can get a feel of it's own character (the instant torque, the unique sound), but also one gets to introduce/interact with a entire younger generation when showing that it's electric, not just a bunch of older guys talking about the good ol' days. To me this gives it a second life beyond just car clubs.

I've converted many vehicles over the years from go-carts, scooters, cars, and even buses, so the technical hurdles are well understood. Hopefully if you follow my on this journey you'll find that it's not so difficult after all.
Last edited by mdkohler on Sun Nov 10, 2019 2:03 pm, edited 3 times in total.
Marc
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

86_6series wrote: Sun Nov 10, 2019 1:35 pm Why would you take the essence of the 6 series character and change to an unexciting, boring, down right head scratching conversion.

It's taking the life out of a great car. If your going to go from wonderful enjoyment to boring why not convert a classic Pinto.

Then the looks of the car would compliment the conversion.
I get that some people with a lot more experience than I with the 6 series will see this as heresy, but I am not a purist and am willing to experiment.

Conversions don't have to be unexciting and boring. It's really a matter of budget, just like with gas engine upgrades.
To me the life of the car is not just the engine, it's the whole experience. The look is inspiring, the handling is fun, but the enjoyment does not have to come from engine alone. To be honest, the 635 is probably the best looking BMW that has the least performance (compared to the looks/performance ratio of most other BMWs).

If my commute averages 25 mph, why would I need M series performance inside?

I want this to be my daily driver, not just a vehicle I take out on sunny weekends. I'm also in the lithium ion battery industry so it makes sense to integrate that into my daily living, so why not do it in style?
Marc
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Before removing any components, I weighed the vehicle at my local dirt & gravel depot on their scale.

3470 lbs total
1980 front (57%)
1490 rear (43%)

This was with me in it and about a 1/2 tank of fuel.

I don't know how heavy the gas engine is (350#?) or the exhaust system and fuel tank, but I plan to put 265# of batteries under the hood and the same amount in the trunk tucked in behind the rear seats. The e-motor weighs in at 120#.

I will try to maintain good balance and stay under Gross Vehicle Weight (~4100#).
Marc
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Re: Electrifying my '85 635CSi Euro

Post by olympia57 »

mdkohler wrote: Sun Nov 10, 2019 1:49 pm Hi Don,
I understand where you are coming from. But driving electric is not always about saving the planet. True, I have solar panels on my garage that will charge my car emissions free (at no additional cost to me), and I can charge at work (again for "free"), but driving electric also has many other advantages that mean a lot to me.

1) I hate going to the gas station. I hate the expense, the smell, the (lack of) cleanliness, etc. of the experience. Yes, I have done it for 35 years, but it has not gotten any more enjoyable over that time. With electric, I start with a full tank every time I get in the car.
2) As for a classic car or favorite pet, our love for them causes us to spend much money and time (either at the local classic repair shop or vet) keeping them alive. But I see the electrification as an opportunity to drive the car another decade without having to constantly invest time in fixing leaks or seals or any of the many things that a 35 yr old gas motor needs to keep running.
3) Yes, phase 1 with only one electric motor will lower it's performance compared to original (phase 2 with two motors would exceed the original engine's specs). But for my needs, it is fine, as my commute is 25 miles long and it takes me an hour to get there because of traffic. So you can see I won't be missing the additional hp, only the fumes and possible overheating issues of sitting in stop and go traffic.
4) For soul, once you drive electric, you can get a feel of it's own character (the instant torque, the unique sound), but also one gets to introduce/interact with a entire younger generation when showing that it's electric, not just a bunch of older guys talking about the good ol' days. To me this gives it a second life beyond just car clubs.

I've converted many vehicles over the years from go-carts, scooters, cars, and even buses, so the technical hurdles are well understood. Hopefully if you follow my on this journey you'll find that it's not so difficult after all.
Marc ,thank you for taking time to explain the reasons for the conversion, I apologise if I sounded harsh or rude . It is for you to decide what you want and I therefore hope you enjoy the work to be done and the final result when you get there.
It may be that in the not so distant future we will be seeking advice from you as to how to do it ourselves.....
Here in Ireland the wrath of the European Union is about to be inflicted upon us for failing to come even remotly close to the required carbon reduction target and as the motorist is the lowest hanging fruit it is certain that the garrot will be tightend soon, so who knows.
Good luck and post some detailed progress on your project thread.
Don
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Re: Electrifying my '85 635CSi Euro

Post by jps635 »

I guess you've sen this?

https://www.youtube.com/watch?v=610Amyhpzzk

Quite a bit of engineering involved and still has a hori great radiator. Interesting but not for me. Good luck
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Re: Electrifying my '85 635CSi Euro

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Re: Electrifying my '85 635CSi Euro

Post by ron »



What a great project with an absorbing write-up.
They are ALWAYS rustier than you thought!!!!!!
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Re: Electrifying my '85 635CSi Euro

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jps635 wrote: Mon Nov 11, 2019 7:01 am I guess you've sen this?

https://www.youtube.com/watch?v=610Amyhpzzk

Quite a bit of engineering involved and still has a hori great radiator. Interesting but not for me. Good luck
Yes I have, but thanks for sending. High power AC motors (>100kW) still require liquid cooling. My set up is different, with up to two smaller air cooled motors. My inverter will need to be liquid cooled, but only requires a tiny radiator to do so.
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Amazing project! I know of another E9 getting a gen 1 Tesla drivetrain installed (https://www.facebook.com/e9bmw/).

I looked into doing a Tesla swap, but didn't have the money/time/skill to do the necessary modifications to the rear end.

A local company, called Moment Motors (www.momentmotors.com), is converting an E9 with the same drive system I am choosing. That way, I can buy certain components from them, like the adapter for the motor to the transmission, without having to custom design things myself.
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Re: Electrifying my '85 635CSi Euro

Post by Brucey »

in terms of saving the planet, maybe it would have been better to have started with a 6er that was more of a basket case. OK those parts you don't need will hopefully see another life, but even so. If you only drive 25mph on your commute then probably there is another way of doing it (like cycling) which isn't shifting a single human being by dint of also shifting ten or twenty times as much metal/plastic about the place.

It is an interesting project I am sure, and (probably, since the other technologies that might work are failing to gain enough traction in the market) electric power is probably 'the future'. But there is a complicated calculation to be done in terms of continuing to use a vehicle (where the manufacturing cost in terms of pollution etc has already been 'paid for') that pollutes in use vs manufacturing a load of new stuff and using that instead. There is a large penalty in manufacturing all this stuff and you would 'need to drive' quite a long way before it paid for itself in those terms. Converting to a less polluting powertrain is probably not as bad as manufacturing a whole new vehicle though.

Arguably you, the planet, everyone, could be better off if you rode a bike to work and used your solar panels to offset all the pollution caused by all the other stuff that living in a 'developed economy' entails. 'Consuming more to save the planet' is perhaps a contradiction in terms; I'm probably as guilty as many others in this respect (try as I might) but if every soul on the planet consumed as much as we do in first world countries then the planet would be in much worse trouble than it is.

FWIW my 6er does about a thousand miles a year and is fuelled by LPG. I'd have converted it to hydrogen power if it were practical (BMW built a car like this in about 1973....the only thing coming out of the tailpipe was water, more or less....its a shame they didn't pursue this). The LPG conversion entailed manufacture of only ~50kgs of 'more manufactured stuff' and the tailpipe emissions are a lot cleaner (with less CO2 and more H2O) than on gasoline. Not a complete solution but a step in the right direction perhaps.

I recently saw an old episode of 'wheeler dealers' where they had a Maserati BiTurbo which had been converted to electric traction some years ago and they updated it with a new motor, controller, and batteries. I thought the end result was certainly better than the previous conversion and I wasn't hankering for them to reinstate the original engine much (that was probably Maserati's least loveable creation). But all the resources tied up in the previous electric conversion were effectively wasted; in a few year's time is that the likely fate of a conversion that is done today I wonder?

One of my chums has a Tesla and it has many appealing features. But most of the car's controls appear to be routed through a touch-screen interface which you can't work without taking you eyes off the road; not a very clever idea. It also weighs about 2-1/2 tonnes or something, which is simply ridiculous. The drivetrain (including the batteries) has a warranty on it with about five years left to run; I wonder how much the car will be worth in three year's time or so when the warranty is likely to expire (along with the batteries) during the tenure of the next owner....? An electric car that is a few years old and needs a new set of expensive batteries is likely to be worth virtually nothing I suspect.

Anyway, despite my reservations, if I worked in the Lithium battery trade I suspect I'd be keen on doing a similar project myself. I shall certainly be interested to see how you get on.

Out of interest what are you going to do with the PAS and the brake servo? I suspect that the extant system isn't terribly efficient and if you simply ran the PAS pump from an electric motor it would represent a fairly large parasitic load on the car. Probably there is a more efficient alternative means of powering these systems; conversion to an electric steering rack and a different brake servo might make sense?

cheers
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Re: Electrifying my '85 635CSi Euro

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Brucey wrote: Tue Nov 12, 2019 11:50 pm in terms of saving the planet, maybe it would have been better to have started with a 6er that was more of a basket case. OK those parts you don't need will hopefully see another life, but even so. If you only drive 25mph on your commute then probably there is another way of doing it (like cycling) which isn't shifting a single human being by dint of also shifting ten or twenty times as much metal/plastic about the place.

It is an interesting project I am sure, and (probably, since the other technologies that might work are failing to gain enough traction in the market) electric power is probably 'the future'. But there is a complicated calculation to be done in terms of continuing to use a vehicle (where the manufacturing cost in terms of pollution etc has already been 'paid for') that pollutes in use vs manufacturing a load of new stuff and using that instead. There is a large penalty in manufacturing all this stuff and you would 'need to drive' quite a long way before it paid for itself in those terms. Converting to a less polluting powertrain is probably not as bad as manufacturing a whole new vehicle though.

Arguably you, the planet, everyone, could be better off if you rode a bike to work and used your solar panels to offset all the pollution caused by all the other stuff that living in a 'developed economy' entails. 'Consuming more to save the planet' is perhaps a contradiction in terms; I'm probably as guilty as many others in this respect (try as I might) but if every soul on the planet consumed as much as we do in first world countries then the planet would be in much worse trouble than it is.

FWIW my 6er does about a thousand miles a year and is fuelled by LPG. I'd have converted it to hydrogen power if it were practical (BMW built a car like this in about 1973....the only thing coming out of the tailpipe was water, more or less....its a shame they didn't pursue this). The LPG conversion entailed manufacture of only ~50kgs of 'more manufactured stuff' and the tailpipe emissions are a lot cleaner (with less CO2 and more H2O) than on gasoline. Not a complete solution but a step in the right direction perhaps.

I recently saw an old episode of 'wheeler dealers' where they had a Maserati BiTurbo which had been converted to electric traction some years ago and they updated it with a new motor, controller, and batteries. I thought the end result was certainly better than the previous conversion and I wasn't hankering for them to reinstate the original engine much (that was probably Maserati's least loveable creation). But all the resources tied up in the previous electric conversion were effectively wasted; in a few year's time is that the likely fate of a conversion that is done today I wonder?

One of my chums has a Tesla and it has many appealing features. But most of the car's controls appear to be routed through a touch-screen interface which you can't work without taking you eyes off the road; not a very clever idea. It also weighs about 2-1/2 tonnes or something, which is simply ridiculous. The drivetrain (including the batteries) has a warranty on it with about five years left to run; I wonder how much the car will be worth in three year's time or so when the warranty is likely to expire (along with the batteries) during the tenure of the next owner....? An electric car that is a few years old and needs a new set of expensive batteries is likely to be worth virtually nothing I suspect.

Anyway, despite my reservations, if I worked in the Lithium battery trade I suspect I'd be keen on doing a similar project myself. I shall certainly be interested to see how you get on.

Out of interest what are you going to do with the PAS and the brake servo? I suspect that the extant system isn't terribly efficient and if you simply ran the PAS pump from an electric motor it would represent a fairly large parasitic load on the car. Probably there is a more efficient alternative means of powering these systems; conversion to an electric steering rack and a different brake servo might make sense?

cheers
Hi Brucey, I appreciate your point of view but I didn't post my project here to get into a debate about justifying electrical transportation. I've been involved with electric cars since the early nineties and have heard every argument similar to what you have made and many others.

I have no idea why you would suggest that I drive more of a beater. Why wouldn't I want to drive a nice car that is in good mechanical shape regardless of the fuel that runs it? I plan on driving it 12-15k miles per year and want something dependable.

I recently was in Amsterdam where there were many bikes (and bike lanes) and I think that would be a wonderful way to commute to work, however that is not a realistic possibility where I live. I also use my vehicle to take my daughter to school 12 along the away so it's not just a one person mover as you assume.

I am glad that you brought up the PAS pump. At first I was thinking of using the existing mechanical PAS pump (as well as the existing A/C compressor) which would be run from a pulley off the tailshaft of the electric motor, just as they are today. I would program the controller to have the motor idle at ~700 rpm when no throttle is applied. However, for the price of the custom aluminum front end accessory plate, the pulley, and tensioner, I think I can purchase electrically driven units, while gaining the flexibility of placing them in more convenient locations and hopefully more efficient than the mechanical options. 2002-2008 Mini Coopers already use electrical 12V PAS pumps (https://www.pepboys.com/dorman-renew-mi ... quantity=1), and I can buy a dedicated electrical A/C compressor to run off of my high voltage pack.
144V DC Compressor
144V DC Compressor
IMG_4464.jpg (40.49 KiB) Viewed 18652 times
I think the PAS pump will consume 1kW when fully loaded and the A/C compressor up to 3.5kW when on high. To me, these things, even if they appear to be parasitic loads, are essential and I have enough energy on board to accommodate their full use without impacting my utility of the car. I also have a dc-dc converter that will replace the alternator to drive all 12V accessories from the main battery pack.
1kW, 144VDC to 12VDC Converter
1kW, 144VDC to 12VDC Converter
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Last edited by mdkohler on Tue Nov 19, 2019 4:54 pm, edited 1 time in total.
Marc
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Re: Electrifying my '85 635CSi Euro

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For fun, I had a guy with a 3D printer make this emblem for me.
E6 Emblem
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Re: Electrifying my '85 635CSi Euro

Post by Brucey »

I appreciate your point of view but I didn't post my project here to get into a debate about justifying electrical transportation. I've been involved with electric cars since the early nineties and have heard every argument similar to what you have made and many others.

I have no idea why you would suggest that I drive more of a beater. Why wouldn't I want to drive a nice car that is in good mechanical shape regardless of the fuel that runs it? I plan on driving it 12-15k miles per year and want something dependable.
I think perhaps you misunderstand me; most people have some kind of idea of a reason why they would do such a conversion and the primary motivations might vary wildly. As I said it seems complicated to me; I've not got any special axe to grind , I'm just wondering what your thoughts are, really. If you have 'heard every argument' maybe there is a simple and cogent POV (or link to one?) that clarifies this in an unequivocal fashion; if so I'm sure it would be of interest to others. In your position I might choose to do a project like this for fun, even if I wasn't convinced about any of the other benefits.

My comment about the car has nothing to do with looking like a beater or not, more that you may as well have bought one with a blown engine and/or gearbox if you are not going to use those parts.

cheers
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Brucey wrote: Wed Nov 13, 2019 10:44 am
I think perhaps you misunderstand me; most people have some kind of idea of a reason why they would do such a conversion and the primary motivations might vary wildly. As I said it seems complicated to me; I've not got any special axe to grind , I'm just wondering what your thoughts are, really. If you have 'heard every argument' maybe there is a simple and cogent POV (or link to one?) that clarifies this in an unequivocal fashion; if so I'm sure it would be of interest to others. In your position I might choose to do a project like this for fun, even if I wasn't convinced about any of the other benefits.

My comment about the car has nothing to do with looking like a beater or not, more that you may as well have bought one with a blown engine and/or gearbox if you are not going to use those parts.

cheers
You are correct that motivations vary greatly for why we do things. You brought up several points that I feel are best dealt in other forums. I can't send you to a single link because you brought up many different angles (i.e. amount of pollution due to manufacturing, consumption per person, wasted resources when trying to transition into something new, layout design considerations of a Tesla, it's weight, it's resale value, etc.) I'd love to sit down over a beer or two and happily discuss each one of these topics in detail. Perhaps on my next trip to Belfest (where my company has a presence) , I can swing over to meet you.

My reasons for this conversion:
1) Don't want to buy gas anymore for multiple reasons (cost, cost variability, lack of convenience, hassle when the station is busy, smell/mess when overflows or drips on paint, environmental impact including oil spills)
2) Don't want to perform general maintenance on an old engine (oil & filter changes, valve adjustments, sensor search and replace, spark plugs, coils, wires, exhaust when it gets rusty, catalytic converter, coolant flush/upkeep, etc.). I know some guys live for this stuff. I do not.
3) Emissions from the car. I have to warm it up before I drive it. It stinks up the garage after I park it inside. Even in 1985 the exhaust emissions stunk, and they aren't any better in 2019.

Thanks for clarification about driving a junker. Yes, finding a car in good mechanical condition with a blown engine and transmission would have been ideal. But those were not available. Even if I did, I wouldn't have been able to have test drove it to see if the brakes or suspension were any good. Also, even now that I'm trying to sell my engine, there are no easy takers as the engines are pretty solid and when they break, people just get them fixed. Hopefully I can come across someone who just blew their engine and will want mine. But the chances that it happens in the next two months, and that we connect, are slim.
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Re: Electrifying my '85 635CSi Euro

Post by Brucey »

thanks for the reply. Yes it certainly is challenging and there are complex issues. FWIW if there is a bad fuel smell from the exhaust when the car starts this is usually caused by overfuelling when the car is cold. One of my mad plans is to have momentary action switches to run the fuel pump and manually prime the inlet manifold using the CSI; I suspect that if the engine doesn't fire instantly, there is often a puddle of fuel on the bottom of the inlet manifold after just a few seconds of cranking. Open loop cars are susceptible to overfuelling when cold but closed loop cars can be well out of adjustment and these faults are masked once the O2 sensor starts to work.

If there is a bad fuel smell after the car is driven into a garage then this usually either means the tank venting system is defective or (more likely) that the fuel hoses under the bonnet are slightly leaky. The latter makes a nasty rubber/fuel smell that will soon fill a small garage if the engine is hot. To find such fuel leaks; the outside of the fuel hoses will smell so badly that just touching them and then sniffing your fingertips will be enough to tell you which hoses are bad. When the engine is cold, with the fuel pump relay jumpered (so that the fuel pump will run), you may see the hoses are actually wet with fuel, once the leak is bad enough.

Of course this only matters much if you are still using the car in its original state. However if you sell the motor on and one of the old fuel hoses ruptures and causes a fire that wouldn't be good either. It is usually the CSI hose which causes this trouble BTW, and that one usually stays on the engine when it is transplanted.

I understand the need for AC where you are and ~3.5kW is about what I'd expect (you certainly notice the difference in consumption when it is on with other fuels). It still sounds like a lot when you consider that you could run about fifteen e-bikes on that power though... :shock:

BTW do you have a good plan for adjusting the ride height once you have converted it? The rear should be fairly easy (eg with blisteins) but the front is likely to be more of a problem. I'd suggest that if you can do, keeping the front axle weight the same and allowing the rear to creep up would be a good idea; IME anything up to 50% of the weight at the back of the car actually improves things over the stock weight distribution, which is a bit nose-heavy. LHD cars are tricky here; in removing the fuel tank you take weight out of the RHS of the car, so are in danger of making the car heavier than it should be on the left side, especially when you don't have a passenger on board.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Re: Electrifying my '85 635CSi Euro

Post by songzunhuang »

mdkohler wrote: Wed Nov 13, 2019 3:14 am For fun, I had a guy with a 3D printer make this emblem for me.
FWIW - I think this will be very interesting and cool to see. Love the emblem.
Bonus, your car is the same color as mine. :-)

Also, I went to school at UT in Austin so fun to see an Austinite going for this.
-----
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Brucey wrote: Thu Nov 14, 2019 1:53 pm
If there is a bad fuel smell after the car is driven into a garage then this usually either means the tank venting system is defective or (more likely) that the fuel hoses under the bonnet are slightly leaky. The latter makes a nasty rubber/fuel smell that will soon fill a small garage if the engine is hot. To find such fuel leaks; the outside of the fuel hoses will smell so badly that just touching them and then sniffing your fingertips will be enough to tell you which hoses are bad. When the engine is cold, with the fuel pump relay jumpered (so that the fuel pump will run), you may see the hoses are actually wet with fuel, once the leak is bad enough.
I didn't mean to imply that there was a fuel smell (either when starting it or when turning it off in the garage). I was strictly speaking of the exhaust fumes. Since my other cars are an Infiniti M35 hybrid and a Volvo XC60 plug-in-hybrid, I am used to driving into the garage in EV mode which has probably made me more aware of the exhaust fumes from the 6 after pulling in and turning off the engine.
Marc
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

Brucey wrote: Thu Nov 14, 2019 1:53 pm
BTW do you have a good plan for adjusting the ride height once you have converted it? The rear should be fairly easy (eg with blisteins) but the front is likely to be more of a problem. I'd suggest that if you can do, keeping the front axle weight the same and allowing the rear to creep up would be a good idea; IME anything up to 50% of the weight at the back of the car actually improves things over the stock weight distribution, which is a bit nose-heavy. LHD cars are tricky here; in removing the fuel tank you take weight out of the RHS of the car, so are in danger of making the car heavier than it should be on the left side, especially when you don't have a passenger on board.

cheers
I loaded up the batteries that I plan to put in the trunk.
IMG_3938a.jpg
IMG_3938a.jpg (201.55 KiB) Viewed 18568 times

The extra 250 lbs lowered the car a little over 3/4".

Unloaded measurement from wheel well:

unloaded height from wheel well
unloaded height from wheel well
left rear empty 3.JPG (1.51 MiB) Viewed 18568 times

Loaded measurement from wheel well:
loaded height from wheel well
loaded height from wheel well
rt rear loaded 4.JPG (1.56 MiB) Viewed 18568 times

I think my Bilsteins are on their middle setting, so I can probably move it up to the top ring to compensate for this amount of sag.

As for the front, I have no idea what the current engine weighs. The electric motor will weigh 120 lbs, the controller and adapter plate another 50 lbs, and the front batteries 250 lbs.

Thanks for reminding me about the missing weight from the fuel tank. I can place my charger and dc-dc converter back there to help a little.
Last edited by mdkohler on Sat Nov 23, 2019 1:30 am, edited 1 time in total.
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

songzunhuang wrote: Thu Nov 14, 2019 6:52 pm
mdkohler wrote: Wed Nov 13, 2019 3:14 am For fun, I had a guy with a 3D printer make this emblem for me.
FWIW - I think this will be very interesting and cool to see. Love the emblem.
Bonus, your car is the same color as mine. :-)

Also, I went to school at UT in Austin so fun to see an Austinite going for this.
Thanks Song, reading about your adventure(s) inspired me to embark upon this project, although after your updates, I knew that I wanted to find a car with everything already fixed! :D

If you ever make it back to Austin, PM me and let me know.
Marc
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Re: Electrifying my '85 635CSi Euro

Post by 86_6series »

Marc,

Your explanation for converting to electric was an interesting read.
Your point about the maintenance is very true, and the almost trouble
free with this conversion does eliminate the drive train headaches.

Are you going to tie in the brakes to add charging to the batteries,
or because of your short commute it won't be necessary.

Will there be one electric motor driving the shaft to the diff or
a motor for each axle?

I'll be awaiting your posts on the progress.
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Re: Electrifying my '85 635CSi Euro

Post by mdkohler »

86_6series wrote: Fri Nov 15, 2019 1:25 pm Marc,

Your explanation for converting to electric was an interesting read.
Your point about the maintenance is very true, and the almost trouble
free with this conversion does eliminate the drive train headaches.

Are you going to tie in the brakes to add charging to the batteries,
or because of your short commute it won't be necessary.

Will there be one electric motor driving the shaft to the diff or
a motor for each axle?

I'll be awaiting your posts on the progress.
Yes, the motor will have regenerative braking so every time I slow down, the motor will turn into a generator and recharge the batteries. This will also extend the life of my brake pads.

The current design is to connect the electric motor directly to the input of the transmission, just like the engine is now. I will not have a motor for each axle.
Marc
Austin, Tx
1985 635CSi Euro
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