Smoke testing

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635sharknose
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Smoke testing

Post by 635sharknose »

I did some smoke tests on my car to find vacuum leaks.
Found one in the edge of the air check valve (part.no.1163170627), managed to seal it with some silicone sealant.
I did find no other leaks but that could be due to the fact I don't quite know where to connect the smoke tester.
Tried to connect to the fuel pressure regulator (part.no 13531711540) but the smoke just blew out of the intake manifold, from the blue tube show on the photo below (I blew the smoke in at the yellow arrow in photo 1 and it came out at the yellow arrow in photo 2).
Is that normal??

Any tips how to perfectly perform a smoke test and where best to connect are welcome. [-o<

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635sharknose
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Re: Smoke testing

Post by 635sharknose »

I think I found it.
The blue tube attached to the bottom side of the manifold needs to be connected to a small brown tube that goes into the interior, to which I believe goes to an interior sensor.

Can someone confirm this?

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hornhospital Online
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Re: Smoke testing

Post by hornhospital »

Confirmed. It uses manifold vacuum to draw interior air through the interior temperature sensor.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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635sharknose
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Re: Smoke testing

Post by 635sharknose »

Great! Thanks for the confirmation. Will connect and proceed with the smoke test to make sure everything is sealed properly.
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86_6series
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Re: Smoke testing

Post by 86_6series »

Send smoke thru the AFM tube at the front of #6.

https://www.realoem.com/bmw/enUS/showpa ... Id=13_0262
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635sharknose
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Re: Smoke testing

Post by 635sharknose »

Will do, thanks Bob!
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emac
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Re: Smoke testing

Post by emac »

This may help to attach the smoke machine to the intake.....
https://www.amazon.com/gp/product/B07QX ... UTF8&psc=1
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86_6series
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Re: Smoke testing

Post by 86_6series »

Here's a post I sent a couple of days ago.

I have an easy way to do a smoke test.

Purchase a bee smoker:
https://www.bing.com/search?q=bee+smoke ... HRDEF&sp=1

Use an empty plastic soda bottle and tape a small hose to spout of smoker
and the top of the bottle. Cut the bottom of the bottle and tape to end of rubber boot
#6.
https://www.realoem.com/bmw/enUS/showpa ... Id=13_0262.

Load the smoker with your choice of smoke chips, light the chips and pump the smoke thru the system.

Works for me every time, also not an expensive solution.

Good luck.
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