g-mack
Active Member
eh?? never heard that one before!! which vid was that? mrs will **** herself when i tell her! lol
g-mack
Active Member
air filter is new.
is it safe to drive it with no pipe on the inlet of the turbo? if so i will do that as it could eliminate any intake pipe problems or vibrations!
g-mack
Active Member
collet was next to valve spring so yea retrieved and re fit as its only a few weeks old. also still looked new!
right, so next thing to try is removing air intake pipes right up to turbo!
i will update when i get results!
g-mack
Active Member
AAAAGGGGHHHHH!!! this is driving me nuts!!
so removed all airbox pipes from wing to turbo and STILL booming!!
so recap
booming when revved. when stationary can here it a little but more so when driving. dip the clutch and its gone!
noise is louder in driving seat and def quieter in rear seats.
checked exhaust and changed gaskets right up to block. been under car when being revved and def not coming from exhaust.
removed props one at a time.
set reset and reset again valve clearances.
new head gasket
air piping up to turbo removed.
so what next??
engine & gearbox mounts? i don't have any vibrations but could they coarse an exhaust like booming?
so removed all airbox pipes from wing to turbo and STILL booming!!
so recap
booming when revved. when stationary can here it a little but more so when driving. dip the clutch and its gone!
noise is louder in driving seat and def quieter in rear seats.
checked exhaust and changed gaskets right up to block. been under car when being revved and def not coming from exhaust.
removed props one at a time.
set reset and reset again valve clearances.
new head gasket
air piping up to turbo removed.
so what next??
engine & gearbox mounts? i don't have any vibrations but could they coarse an exhaust like booming?
jamesmartin
Well-Known Member
the only time valve stick is when they are bent
Or carboned up.
g-mack
Active Member
is it the air intake sound that makes you say that?
Hi James.
I've had one stick in a VW engine, not bent but seized for some strange reason. High mileage engine in which you expect all tolerances to open, very odd. 'Twas fine after a valve and guide change.
I would have suggested a burned seat as a result of running with the collet missing, but the OP says that it was 'booming' before he had the head off.
Given that the car was bought with the booming happening, it makes me wonder if it was a reason for the sale? And maybe a broken or slipped cam belt in the past?
I've had one stick in a VW engine, not bent but seized for some strange reason. High mileage engine in which you expect all tolerances to open, very odd. 'Twas fine after a valve and guide change.
I would have suggested a burned seat as a result of running with the collet missing, but the OP says that it was 'booming' before he had the head off.
Given that the car was bought with the booming happening, it makes me wonder if it was a reason for the sale? And maybe a broken or slipped cam belt in the past?
Yes. At first I thought that I could hear a leaking injector or heater plug seal, but as you moved the camera down, the deeper noise became apparent.
g-mack
Active Member
when i bought it there was no booming, but the air intake definitely popped like on the vid
If it were a stuck/burned/broken valve, then:-
If you put your hand near the inlet (with the hose off as in the video) can you feel any unevenness in the flow into it? That would be a good test in a non turbo car, but the turbo will, to some extent, mask the effect that the hot air being blown back out into the inlet manifold would have. Worth a try though.
If you put your hand near the inlet (with the hose off as in the video) can you feel any unevenness in the flow into it? That would be a good test in a non turbo car, but the turbo will, to some extent, mask the effect that the hot air being blown back out into the inlet manifold would have. Worth a try though.
g-mack
Active Member
haven't heard that one, will give it a go, also saw a youtube vid holding paper over tailpipe, if it flaps (gets sucked back to pipe) there is a valve problem, so will give that a go too.
are there any good ways to cure a sticky valve, or is my head coming off (again)
g-mack
Active Member
does this sound feasible?
whilst inspecting the original head (now off car) i discovered ALL 4 exhaust valve seals were sat at top of spring!! so effectively no seal at all.
i understand oil will be getting into bores, but surely as the exhaust valve opens and the spent oxygen is forced out, a lot of it is going to be rushing past where the seal should be. causing loud exhaust like droning?
or am i wrong?
i have researched this to death and never found this theory
whilst inspecting the original head (now off car) i discovered ALL 4 exhaust valve seals were sat at top of spring!! so effectively no seal at all.
i understand oil will be getting into bores, but surely as the exhaust valve opens and the spent oxygen is forced out, a lot of it is going to be rushing past where the seal should be. causing loud exhaust like droning?
or am i wrong?
i have researched this to death and never found this theory
