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MH Vehicle Solutions
18-12-2010, 16:43
Having re visited my five today, it runs spot on, but i have fumes coming from the pot that sits on the top of the oil return to sump, the car was perfect before i did the headgasket, now the pipe ontop of the swirl pot has smoke coming from it when not connected, and unless its faced upwards oil comes from it. Could this be a blockage in the return? I have a catch tank to fit as i am told this will remedy it, but figure there must be a reason why it is doing it now and wasnt before?apart from this the car runs fine, but obviously dont want to drive it like it, does anybody have any ideas or what to look for?thanks :)

scratcher
18-12-2010, 18:24
It could be from the condensation, cold or left over from when the gasket went.
Does it breath heavily from the filler if you pop the cap off?
And do you have the OE breather set up or the 'cup mod'?

Brigsy
18-12-2010, 19:05
Give it a run out, see if it cleares. All gtt's breathe a bit in my experience.

If its chucking oil out the breather though do a comp test, the rings might be damaged?

tom t
18-12-2010, 19:09
definatley take it for a run bud.

Tony Walker
18-12-2010, 21:55
not the most healthy way of testing but blow down the pipe to the sump make sure its clear, if its fine then you'll be ok, take a look at a modern sealed system when you take off the oil fill cap while its running. All cars pass fumes round the breather system.

MH Vehicle Solutions
19-12-2010, 13:59
Checked rings etc while head was off it was all pretty fresh, my only concern is i took swirl pot off and blew through it, that was clear, refitted it and blew through it and it pressurised if that makes sense, i know the oil return to sump is a small diameter but should i be able to blow through it?wondering if this is blocked causing the problems i am experiencing??

Adam 005
19-12-2010, 15:47
my gt breaths heavy and has never had any problems in 20000 miles:)

MH Vehicle Solutions
19-12-2010, 17:57
turbo oil seals have gone, unsure if this is causing my other problems, but turbo is off and once i get my other on there i can fault find properly/see if it was linked :crap:

Adam 005
19-12-2010, 20:29
it seem your going round in circles with this problem.

Tony Walker
19-12-2010, 22:26
Just leave the swirl pot off then. have both pipes to a catch tank.
Higher pressures in the sump will result in high pressures at the turbo return. id keep the turbo on and remove the swirl pot see how it goes.

MH Vehicle Solutions
20-12-2010, 22:16
yes i dont seem to be getting anywhere, what would/could be the cause of excessive crankcase pressure?Because as Adam has said to me it seems like what is happening is oil is coming from the crank case breather and going through the breathing system, this is exactly what it is doing, and this excessive pressure means the oil is passing the turbo oil seals and going through the exhuast :confused: Is there a probable cause?

scratcher
20-12-2010, 22:22
Do you have the one way valve in the inlet manifold still and is it working properly?
Have you done a compression test to rule out worn rings?

MH Vehicle Solutions
20-12-2010, 22:31
It is blanked off, but only done this recently. I am going to do a compression test but am pretty sure its not rings, fingers crossed i guess but ill update when i can rule this out

Tony Walker
21-12-2010, 22:57
Only thing that can cause this is blocked breathers and/or worn rings. check another 5 first before you condem it. difficult to say without seeing it but they can breath fairly heavy. what psi are you running at and how much oil accumulates in the catch tank? theres also a sort of gallery along the top of the rocker cover, this gets filled with carbony rubbish, good idea to make sure thats clear as that helps oil lubricate the valve springs/rockers.
If your breathers are clear then compression test is your next test. with fingers crossed:agree:

MH Vehicle Solutions
21-12-2010, 23:15
What sort of readings should i expect, i will try and get to it tomorrow afternoon and compression test it, eek. many thanks

MH Vehicle Solutions
21-12-2010, 23:38
i was also wondering what the minimum thickness of the head would be before it raises the compression too much, if anybody knows this too?i know my head has had lots of money spent on it in the past and it had the thicker gasket fitted already, but I didnt measure it just faced it and put it back on, just trying to rule things out :) thanks

IANMM
22-12-2010, 08:53
you can put 2 head gaskets on to raise it up and i cant remember the exact size but i think its about 73mm im sure someone can remeber

Adam 005
22-12-2010, 20:49
over skimed head will not cause your probs:)

MH Vehicle Solutions
22-12-2010, 22:00
i just did a quick test
1- 150psi
2- 80psi
3- 150psi
4- 80psi

:crap:

James5
22-12-2010, 22:01
i just did a quick test
1- 150psi
2- 80psi
3- 150psi
4- 80psi

:crap:

Not looking good try a wet test on the cylinders that are down and see if it improves on those cylinders:agree:

MH Vehicle Solutions
22-12-2010, 22:11
sorry for my ignorance what is a wet comp test?cheers

Tony Walker
22-12-2010, 22:18
seems like odd results, 2 good cylinders and 2 very bad? Think i'd do it again and a wet test. have a look on some compression test procedures for a good method.

MH Vehicle Solutions
29-12-2010, 22:32
Wet test brought the low readings upto 120psi, then slowly came down again as i kept turning the engine over, assume this proves its rings, took head off again couldn't see anything wrong. I have always been told to put petrol/brake cleaner ontop of the pistons and obviously if the rings are worn it will slowly pass them, it didnt do this and theres no movement/rocking of the pistons. Going to strip it out and fit a set of rings/shells while and relap the valves and go from there, half tempted to spend a few quid on it, and do a nice rebuild, any ideas or suggestions?

Adam 005
30-12-2010, 10:43
i would go for a nice rebuild using new parts.
Piston and line set
big end and main bearings and thursts
top and bottem gasket kit
timing chain and tensioner
:):):)