bmw m635 itb,s

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bm0635
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Joined: Fri Oct 12, 2018 1:03 am
Location: victoria

bmw m635 itb,s

Post by bm0635 »

engine is being rebuilt by pip barker, head chief mechanic of the old bmw jps team, he is retired but agreed to rebuild my engine,
broken valve spring.
throttles, the yellow caps, do you just pull them off carefully, also the vacuum brown rubber caps, took them off and cleaned out thoroughly, put rubbers back on, how does this work if you then seal them, how does air get in or out.
regards
richard
plip1953
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Re: bmw m635 itb,s

Post by plip1953 »

If it's the yellow caps I think you mean, aren't they intended to be single use only? And wasn't there something about new ones were invariably blue and therefore even with a casual glance you could see if the ITBs had been "tampered" with.
Phil
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bm0635
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Re: bmw m635 itb,s

Post by bm0635 »

hi, thanks for the reply, so do you break them to get them off, just want to clean the idle screws beneath them, also the rubber caps, can you let me know how they work.
regards richard
TimU
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Re: bmw m635 itb,s

Post by TimU »

bm0635 wrote: Tue Jan 31, 2023 9:12 pm hi, thanks for the reply, so do you break them to get them off, just want to clean the idle screws beneath them, also the rubber caps, can you let me know how they work.
regards richard
Wouldn't Pip be doing this when he gets the engine? Or are you doing some of the pre-work before sending it down?
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bm0635
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Location: victoria

Re: bmw m635 itb,s

Post by bm0635 »

hi, he is doing the engine only, he has the block with the head, all the rest of the bits i took off and are cleaning them and buying all new pipework and bits, have completed all new seals on the gearbox, so i was cleaning the itb,s, when i came across the caps and the rubbers, the rubbers have a spigot that goes right thru' the inside of the throttle, then you put the rubbers back and it is sealed, so what do they do, and i cannot get the yellow caps off
regards
richard
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Da_Hose
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Re: bmw m635 itb,s

Post by Da_Hose »

Sounds like you are talking about the balancing ports. You connect your manometer to them, and then are able to balance out the intake flow. Best approach is to use a liquid, 6-port manometer. The caps are just plain old black rubber.

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1987 M6 - My dream car
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Re: bmw m635 itb,s

Post by dlvad »

As for M88/S38 ITB Adjustment Screw Cap replacements I've ordered multiple sets from Pelican Parts...
https://www.pelicanparts.com/More_Info/ ... ULEALw_wcB
DV
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