Plenum Gasket "lifted" By A Few Mm

[joeyjoejoejuniorshabadoo]

hey guys, was changing my plugs and i noticed that my plenum seems to have lifted by 2-3mm

is it something that i should just tighten and forget? does it need a new gasket? what could have caused the issue?

the car still makes and holds 18psi with no excess noise...

you can also see all the filth around the gasket

it is however probably 3-500rpm laggier... at first i thought i was just imagining it...

?

[PM-R33]

Yep change the gasket dude. The gasket has probably gone a bit hard in some areas and caused the plenum to not be flat anymore. I'd just put it down to age.

[joeyjoejoejuniorshabadoo]

how the hell do you get to the bolts on the bottom tho?

[PM-R33]

It's a pain in the ass man. Get yourself some ratchet spanners, only way i would ever do it again.

[joeyjoejoejuniorshabadoo]

hmmm.... might get me a mechanic.... it looks like a hell pain in the ass

any other gaskets worth looking at or just oem?

[PM-R33]

Hahaha fair enough.

[joeyjoejoejuniorshabadoo]

shit.... just had a thought...

car was riching out and fouling plugs, so we retuned it from the ground up about 3 months ago...

is there any chance that air was escaping through the gasket and thus making the car rich?

because that means if i fix it then i'll be leaning the car out...

quick retune perhaps?

[Mr. Untouchable]

the plenum top section isnt that bad to get to mate. (Geee it would be a good chance to fit a plazmaman plenum whilst your at it......)

[joeyjoejoejuniorshabadoo]

lol, you pay yeah?

exhaust stud 6 is also missing.... AGAIN

[Mr. Untouchable]

Also, for this type of job and for almost any job, one of these bad boys are the ultimate. the whole case is around 60-70mm long and they fit in the tighest of tight places, yes where the sun does not shine.

Tough as nails, I regularly slug mine with a 4 pound hammer. Only goes up to 13mm But you can by extra sockets (any brand) if you need them bigger. this & a set of ratchet spanners is very handy indeed.

made by Teng tools.

[Mr. Untouchable]

lol, you pay yeah?

haha I would if I could mate.

the stock one has 9 bolts, all 12mm heads. remove the crossover pipe and TB... easy peasy

[joeyjoejoejuniorshabadoo]

cool cool....

i'm just worried about the tune tho...

[joeyjoejoejuniorshabadoo]

double post fail...

[Mr. Untouchable]

replace the gasket, then get it on a dyno to check afr's.

\

[bozodos]

Interesting, mine has the exact same thing going on hamish, and I also have the car runningly stupidly rich and fouling plugs all the time. It dosen't look like it would be a massive job to take it off, apart from the bolts lol, I'm used to having to pull my cooler piping and associated hosing all the time to get to the spark plugs anyway.

ratchet spanners are a must on a Skyline IMO, too fkn hard and complicated to do a lot of things otherwise.

[STATUS]

tweak the outer ones and with the car idling spray aero start or brake / carb cleaner around the gap. If the idle lifts (or any perceptible change) you have a leak.

Remember the gasket is rubber and around 3mm thick so it should not look flush, but the oil around it is a bit sus

Mind you when we were chasing your leak on the dyno i remmember spraying cleaner around there and it was fine @ idle. (but it was not oily then) then we found the split cooler elbow.

[PM-R33]

Yeah what is with all that oily residue on the outside of the plenum

I think if the tune was thrown out by that the leak would have to be pretty substantial and you would notice is very easily. I wouldn't worry about the tune side of things, just fix it up and if you are worried chuck it back on Trents dyno.

Edited February 15, 2010 by PM-R33

[joeyjoejoejuniorshabadoo]

hmm... what could the residue indicate?

i'll tighten the bolts and check.... the idle is starting to hunt a tiny bit.

[Guilt-Toy]

REMEMBER.

There are 2 types of gaskets on the R33 skyline. One is completly all rubber and the other is rubber with metal bracing on the insides to keep its shape.

100% of the time i have seen the the complete rubber ones have leaked and caused ALL kinds of issue.

Do not start this job untill you get the gasket that has metal inside to keep its shape.

If you can bend the gasket """" IT IS THE WRONG ONE """"

And to rest your mind about the leaking issue (tuning).. when they leak from there the plenum will SCREAM "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE" very high pitched sound. (personal experience - hence the 2 types of gasket comment)

[joeyjoejoejuniorshabadoo]

thanx ant i'll make sure to check first!

i would have thought there would have been a noise if it was leaking too.... but the thing that gets me is the residue all around the gasket...

that engine bay copped 3 cans of degreaser only 6 months ago...