Fuel cooler on my 1987 L6?

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six shooter

Fuel cooler on my 1987 L6?

Post by six shooter »

Fuel cooler from the AC pipe?

That is what I have been told I have.

It is a small canister that has fuel running in and out ( I guess)
it is part of the AC system. That hose from the AC compressor
is leaking ( freon) I need to get a new hose made.

Has anyone else had to do this?

Parts catalog does not show the fuel cooler/AC hose.

Thanks
donudel

Re: Fuel cooler on my 1987 L6?

Post by donudel »

six shooter wrote:Fuel cooler from the AC pipe?

That is what I have been told I have.

It is a small canister that has fuel running in and out ( I guess)
it is part of the AC system. That hose from the AC compressor
is leaking ( freon) I need to get a new hose made.

Has anyone else had to do this?

Parts catalog does not show the fuel cooler/AC hose.

Thanks
An attempt to cool the fuel to avoid vapor lock situations.
Don
alpinacsi

Post by alpinacsi »

RealOEM.com shows the hose under the fuel supply system here: (part # 1)

http://www.realoem.com/bmw/showparts.do ... g=16&fg=15

and under the heat and air coolant lines here: (part # 16)

http://www.realoem.com/bmw/showparts.do ... g=64&fg=60
Chris Wright

Post by Chris Wright »

Some have posted that the A/C hose with the built-in fuel cooler is no longer available, but since it is buried in a separate diagram they may not have found it.

You can try the dealer, but your best bet is to take the hose to a shop that makes A/C-Hydraulic hoses, they will make you a replacement hose using your original metal fittings so that you save the fuel cooler.
six shooter

Great Idea!

Post by six shooter »

Thanks Chris,
I will take all the rubber hoses in to be made.

I really don't think the car needs a fuel cooler,

but I want to keep my L6 as stock as possible.
GWL

Re: Great Idea!

Post by GWL »

six shooter wrote:Thanks Chris,
I will take all the rubber hoses in to be made.

I really don't think the car needs a fuel cooler,

but I want to keep my L6 as stock as possible.
If you look close at the fuel flow you will see that the fuel is cooled on the return line. When I first saw that my M6's had been bypassed I thought that it was used to cool the fuel on the way to the injectors and was all hot to reinstall the system. But after seeing that it cooled the fuel on the way back to the tank, I just left it disconnected. IIRC BMW dropped this feature at some point after my car's 12/86 build date.
six shooter

Post by six shooter »

I have a 11/86 manufacture date on my 1987 L6.

Thanks for the info about the fuel cooler.

I see that it cools the return fuel :( If it cooled the

intake fuel then I would be more interested in keeping the system.


For those of you that have done this procedure a picture

would be wonderful.

Thanks

Greg[/i]
GWL

Post by GWL »

six shooter wrote:I have a 11/86 manufacture date on my 1987 L6.

Thanks for the info about the fuel cooler.

I see that it cools the return fuel :( If it cooled the

intake fuel then I would be more interested in keeping the system.


For those of you that have done this procedure a picture

would be wonderful.

Thanks

Greg[/i]
On my car the bypass is done here. See circle on drawing. A short piece of fuel line is all you need to replace fuel line seven.
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alpinacsi

Post by alpinacsi »

Isn't the fuel going to be the hottest as it bypasses the regulator? So then it would make sense to cool it at the hottest point. It then goes back to the tank and mixes with cooler fuel.

On one of my boats the fuel runs in a closed loop and does not return to the tank so the bypassed fuel gets very hot and goes thru a water cooled heat exchanger before it is mixed with fresh fuel back to the supply side of the rail. My other boat has a cooler on each return line as it leaves the fuel rail and before it returns to the tank.
dividedbydrew

Post by dividedbydrew »

So, if my car had a fuel cooler, where would it be? Realoem indicates that my car has one of these but I'll be darned if I can figure out where it is. I have not completely followed the hard fuel lines from the back of the car where the filter and secondary pump are all the way to the engine bay but, what I can see in the engine bay is both the send and return soft fuel lines from the fuel rail going through 13311713470 "connecting pieces" and then connecting to hard lines at the firewall on the driver's (left hand) side. Does this mean I don't have a fuel cooler? A picture of what it really looks like/where it is or some clue as to where it might be would be great. I'm trying to replace all the soft fuel lines on my car but can't seem to make sense of this from the diagrams on realoem. Thanks!
GWL

Post by GWL »

dividedbydrew wrote:So, if my car had a fuel cooler, where would it be? Realoem indicates that my car has one of these but I'll be darned if I can figure out where it is. I have not completely followed the hard fuel lines from the back of the car where the filter and secondary pump are all the way to the engine bay but, what I can see in the engine bay is both the send and return soft fuel lines from the fuel rail going through 13311713470 "connecting pieces" and then connecting to hard lines at the firewall on the driver's (left hand) side. Does this mean I don't have a fuel cooler? A picture of what it really looks like/where it is or some clue as to where it might be would be great. I'm trying to replace all the soft fuel lines on my car but can't seem to make sense of this from the diagrams on realoem. Thanks!
If you have one it will be on the cold side of the refrigeration line. Look at the drawing above. Parts 1 & 2 are on the passenger side of the engine while parts 4 & 5 extend accross the engine bay to Parts 6 & 7.
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winfred
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Joined: Sat Aug 25, 2007 3:37 am
Location: louisiana

Post by winfred »

it'll be on the large ac line coming out of the firewall, just about everything came with a fuel cooler around 87, and then it was gone, probably decided it didn't do squat
3/81 633 m30b35 & getrag 260/6, motronic 1.3 -sold

86 635 with nearly all goodies from rotted away 85 m635 including the m88/3, tuning in progress on motronic 3.3.1
dividedbydrew

Post by dividedbydrew »

Do the hard lines (parts 4 and 5) run along the firewall? If so, on the engine bay side (not behind the firewall? I don't seem to see anything there and I think I have properly identified the AC cold line heading into the firewall on the right-hand/passenger side but nothing obvious connected to it.

Am I correct in the assumption that most cars until sometime in 1987 should have these? That's what it sounded like from other posts but I want to confirm. I suppose it is possible it was removed by a previous owner but I wouldn't think they would have gone through the trouble of removing hard lines 4 and 5. I'll take a closer look again tonight.
dividedbydrew

Post by dividedbydrew »

I just got home and did a good thorough look at the right hand side of the car. I can clearly see the AC lines going into and out of the firewall and can trace them to the receiver/drier, out in front of the radiator and back and then to the compressor and back to the firewall. I see no evidence of a fuel cooler in those sections. Did I look in the right place? If so, how common (or not common) are these things on pre-87 cars?

Also, is the canister next to the receiver/drier the charcoal canister? It has what looks like 2 fuel lines. One goes to the evaporative purge valve (opposite the idle air stabilizer valve on the intake boot) and the other disappears at the firewall on the right hand side of the car where it attaches to a hard line. If so, are these lines worth replacing while I'm at it? I imagine they only carry vapors and not actual liquid fuel but maybe I'm wrong.
nataku83

Post by nataku83 »

It looks to me like the fuel cooler would be a sleeve that fits around one of the a/c return lines. I'd trace the fuel hose going back from the fpr, as it would almost certainly have to be in the engine bay - especially on a car without rear a/c.

The lines going to the cannister (yes, it is located near the drier) absolutely should not contain liquid fuel - however, they attach to the intake through a valve, and if degraded, can cause vacuum leaks when the valve opens
GWL

Post by GWL »

nataku83 wrote:It looks to me like the fuel cooler would be a sleeve that fits around one of the a/c return lines.
Exactly! The sleeve is behind the heat shield between the engine side of the wheel well and the heat shield. It looks like a fat tube with two fuel lines attached. The lines go into the firewall and extend across the cowl and turn back into the engine bay on the driver side. I tried to take a picture but failed because I have Euro snake headers and the heat shield completely hides the cooler.
dividedbydrew

Post by dividedbydrew »

I think I've gotten the info I needed so THANKS! I only have 4 lines coming or going at the right hand side of the engine bay near the firewall. I have identified them as the 2 AC lines, brake line going into front right wheel well, and evaporative line (presumably from gas tank) going to the charcoal canister. Nothing else at this corner of the engine bay in my car that isn't clearly electrical or the washer fluid hose. A picture of this fuel cooler would still probably be useful if anybody can ever get one without too much hassle mostly because I'm curious. So, again, are these common on pre-87 cars or not? I'm trying to figure out if my car never had one or if it was removed by a PO.
GWL

Post by GWL »

dividedbydrew wrote:I think I've gotten the info I needed so THANKS! I only have 4 lines coming or going at the right hand side of the engine bay near the firewall. I have identified them as the 2 AC lines, brake line going into front right wheel well, and evaporative line (presumably from gas tank) going to the charcoal canister. Nothing else at this corner of the engine bay in my car that isn't clearly electrical or the washer fluid hose. A picture of this fuel cooler would still probably be useful if anybody can ever get one without too much hassle mostly because I'm curious. So, again, are these common on pre-87 cars or not? I'm trying to figure out if my car never had one or if it was removed by a PO.
If the cooler was removed, he would have to have replaced the AC lines to the interior. It is not likely that he would have done so because all you do is re-route the fuel lines to bypass the cooler completely and not incur the line replacement costs.
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winfred
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Location: louisiana

Post by winfred »

it's not common outside of 1987-88, it will always be on the return line between the firewall where it exits and the compressor where it enters no matter what car its on
3/81 633 m30b35 & getrag 260/6, motronic 1.3 -sold

86 635 with nearly all goodies from rotted away 85 m635 including the m88/3, tuning in progress on motronic 3.3.1
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sskang
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Post by sskang »

I have mentioned this before in another thread but the AC pressure line with cooling chamber is NLA at BMW. What you get instead is an AC hose without the chamber.

I have been driving the car without fuel cooling system in the notoriously hot Tokyo summer with no major issue.

When doing so, you should get part number 13531726960
which is a bent rubber fuel hose used to connect the pressure regulator and the fuel line.
sskang
1987 M6 Alpinweiss
Tokyo, Japan

"Aller guten Dinge sind Sechs"
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