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Model specific boards => Golf mk4 => Topic started by: Pez on 13 December 2012, 16:03

Title: Finding a boost leak.
Post by: Pez on 13 December 2012, 16:03
Just been to look at a 1.8T that I'm thinking about buying, the owner says he thinks it might have a boost leak. What's the best way to find out where it's coming from and is it just the hoses that are likely to be the cause?
Thanks in advance -Pez
Title: Re: Finding a boost leak.
Post by: Dalo Harkin on 13 December 2012, 17:03
boost leaks leak oil - start there.

Yes all the pipes under the plate on the inlet are most common and then the PCV system  :wink:
Title: Re: Finding a boost leak.
Post by: Pez on 13 December 2012, 20:26
boost leaks leak oil - start there.

Yes all the pipes under the plate on the inlet are most common and then the PCV system  :wink:
Cheers mate.
Title: Re: Finding a boost leak.
Post by: BarryMKIV on 13 December 2012, 22:22
Smoke test.
Title: Re: Finding a boost leak.
Post by: jamie1989 on 14 December 2012, 09:10
1.8t's are pretty easy tbf.

If you cant afford a smoke test I would start from the top of the turbo and follow it all the way down to the intercooler, then from the intercooler to inlet. Even if it means removing all these pipes and check for obvious splits.

If you have found nothing remove the engine covers and check under the inlet manifold youl find a few pipes connected to it, these are under vaccum and perish over time. If they are perished time to invest in new pipes or perfect oppertunity to get a catch can installation.

Goodluck
Title: Re: Finding a boost leak.
Post by: GTi_James on 14 December 2012, 09:16
welcome and i hope you have been saving all your pennies from the paper round!  :whistle:  :laugh:

and first thing i'd do is replace the PVC with a catch can  :wink:
Title: Re: Finding a boost leak.
Post by: tshirt2k on 14 December 2012, 09:35
Just checking pipes won't find you leaks. You need a smoke test or make a boost leak tester using some plumbing bits and a compressor. Pressurise the system and you'll hear the leaks.
Title: Re: Finding a boost leak.
Post by: jamie1989 on 14 December 2012, 10:17
Iv found plenty of leaks before.
Never in my life used a smoke test either.

Using the method above will 9/10 find your leak.

My very best mod was a boost guage this way I always knew if I had a leak. I would recomend every 1.8t have them as they are getting old now and all the boost pipes and vaccum pipes are bound to perished by now.
Title: Re: Finding a boost leak.
Post by: Dalo Harkin on 14 December 2012, 12:53
Just checking pipes won't find you leaks.

I don't have any and I dont have a smoke tester  :tongue:
Title: Re: Finding a boost leak.
Post by: jamie1989 on 14 December 2012, 13:00
 :grin:
Title: Re: Finding a boost leak.
Post by: tshirt2k on 15 December 2012, 12:47
Just checking pipes won't find you leaks.

I don't have any and I dont have a smoke tester  :tongue:

How can you tell? I don't have a smoke tester either! You will never know unless you pressurise your system upto your max boost. Just checking hoses won't tell you if you have a tiny leak that passes a lot of air once under pressure.
Title: Re: Finding a boost leak.
Post by: Dalo Harkin on 16 December 2012, 19:03
it will because you would have oil all over where the split is.

I have replaced EVERY pipe on mine that carries boost and there are no leaks.

Title: Re: Finding a boost leak.
Post by: Chris. on 16 December 2012, 19:15
My boost pipes werent full of oil....think your turbo seals are dying mate.
Title: Re: Finding a boost leak.
Post by: tshirt2k on 16 December 2012, 22:33
No oil in my pipes either. So your saying you can't be sure you dont have leaks because you haven't pressure tested the system up to 20 odd psi.  :undecided:

Even when you think its tightened up. They can still leak, especially with jubilee type clips.