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Leak test done...

Posted: Sun Feb 04, 2007 12:17 pm
by MarkB
I've just done a leak chaeck on my intake system and I can hear air bubbling through the crackcase and oil.

Am I right in thinking this is most likely a problem with the one way valves on the spider pipe?

Help please!!

RE: Leak test done...

Posted: Sun Feb 04, 2007 1:06 pm
by nickb834
isn't it just the cranckcase breather - as in to relieve pressure?

Some air is bound to escape past the rings - especially if the engine has been sat for a long time (overnight) and the oil has drained back down to the sump.

Try it again after a run, see if anything changes.

RE: Leak test done...

Posted: Sun Feb 04, 2007 1:26 pm
by GrahamS4
I thought that was normal Mark.

RE: Leak test done...

Posted: Sun Feb 04, 2007 1:34 pm
by Nige_RS4
Yep, normal.

Posted: Sun Feb 04, 2007 1:34 pm
by MarkB
I could also hear air flowing through the throttle valve area. I was thinking this was it passing the throttle valve.

I must admit the car was stone cold, so i'll do it again after a run

Thanks

Posted: Sun Feb 04, 2007 2:27 pm
by S4TAN
Every time i've had a leak test done i hear a similar 'bubbling' noise - but i have no leaks: I think this is normal behaviour Mark.

Posted: Sun Feb 04, 2007 3:47 pm
by s4woody
yo S4TAN u shud be used to bubbling from dwn below..there,s a hell of alot of lava flowing where u come from.. :FIREdevil:

Posted: Sun Feb 04, 2007 5:36 pm
by S4TAN
yo S4TAN u shud be used to bubbling from dwn below..there,s a hell of alot of lava flowing where u come from..
Ain't that the truth! Fire and brimstone too - must be the vicious curry and lager mix i ingested last night ... :twisted:

Posted: Mon Feb 05, 2007 10:27 am
by JonnyX
Normal. Undo the oil filler cap. I think I fecked my car by accidentally blocking the breather system. Went for a drive
and managed to produce my own 'James Bond style' smokescreen. Not sure my piston rings are too clever any more :-(

Posted: Mon Feb 05, 2007 10:34 am
by MarkB
I remember you posting a while ago that your car wasn't too happy :( How do you think you blocked the breather system?

Mine seems fine at the moment after my attempt though I think I was putting about 30+ psi into the system.

I had removed the oil filler and could hear the oil going "blub blub blub"

Is is normal to hear air passing the butterfly or have a likely got a leak around the TBB? I going to get my self a Samco TBB and F hose so I'll strip and inspect all these soon.

Posted: Mon Feb 05, 2007 12:49 pm
by JonnyX
MarkB wrote:I remember you posting a while ago that your car wasn't too happy :( How do you think you blocked the breather system?

Mine seems fine at the moment after my attempt though I think I was putting about 30+ psi into the system.

I had removed the oil filler and could hear the oil going "blub blub blub"

Is is normal to hear air passing the butterfly or have a likely got a leak around the TBB? I going to get my self a Samco TBB and F hose so I'll strip and inspect all these soon.
Sounds fine to me from what you have said. I would think there would be less
blow-by if the engine was up to temperature. Forged pistons tend to expand a
little when they get hot. My car now has 110k miles. Coupled with my little kinked
hose 'accident' I am going to look into getting it re-ringed. Any ideas from the
mechanics amongst on how long this would take?

Posted: Mon Feb 05, 2007 10:26 pm
by flashyg
Can u re ring without bottom end strip?
Sorry off topic...

Your boost leak test sounds like it went well but any hissing is indicative of a small leak.
G

Posted: Mon Feb 05, 2007 10:44 pm
by shineydave
nope, you need access to the conrod end caps to get the pistons out, you might be able to do it with just a bottom end strip though, ie, sump off. i'm sure someone with more experience will be along shortly to put me right

**edit**

looking at the engine exploded diagrams it looks like the gearbox probably needs to come out to remove the crankshaft

Posted: Mon Feb 05, 2007 11:16 pm
by s4woody
the pistons have to come out from the top which means the heads have to come off..now if you took off the heads in situ then the sump you should be able to undo the big-end caps and push out the pistons and rods..but its so much work you just mite aswell pull the engine out and do it properly..

Posted: Mon Feb 05, 2007 11:36 pm
by shineydave
can you not remove the crank and drop them out of the bottom then?