oil leak from head gasket

[mathew_colville]

I took my car to a mechanic to have a look at where the oil seems to be leaking from, He said it seems to be coming from the head gasket, the mechanic told me he hasnt really worked on these types of cars before (i doubt anyone around taree has), so im just wanting to know if:

this is a common problem

could it possibly be a leak from somewhere else that could make it look like its the head gasket ( i just replaced the rocker cover gasket as this was leaking) but still seems to be leaking from somewhere

could it be just the head bolts need re-torqueing

has anyone used a stop leak product that worked?

from what ive read it could cost from $900 to $5000 dollars ( different types of car) does anyone know roughly how much it will cost for my car, as the mechaninc hasnt done a car like this before he may just over quote it to cover himself, so i want to have some idea of what is a fair price

If i decide to get it repaired, should i be getting anything else done while the engine is apart




I plan to do a compression test if i can find my gauge which seems to have disappeared off the planet
my car is a 4g93t, 99% stock, 154000kms. Have not got any issues with it apart from the oil leak, not loosing coolant, starts first time, drives smooth etc

any other helpful info would be great

thanks
mat

 

[khubner1]

check the cas oring seal> I tend to add some rtv to mine never had an issue with leaks since

questions does it appear to be front or rear of the engine (ie intake or exhaust side bolt side or gearbox side

things to know

cas oring is common leak point
main oil feed for head is gearbox side on the exhaust side.
i've had an oil pressure switch fail and leak through that. if it's gearbox intake side i'd say it's cas oring

 

[mathew_colville]

ill check the cas oring, but the major leak seems to be on the timing belt side

 

[khubner1]

then perhaps it's the crank seals have perished without seeing it after a clean and then a good long drive for a leak to represent it's hard to diagnose

there are no major presurised oil galeries in that part of the head making a oil leak from the gasket uncommon without other assciated leaks like coolant

 

[mathew_colville]

I posted this pic in another thread, I have noticed that where I have drawn the red circle, it leaks from there when the car is running a fair bit, its definitely coming from there, it looked like little oil bubbles coming out, would that be the crankshaft seal possibly? This is only one leak though as most of the oil is higher up the engine

 

[4piknup]

Where is it leaking. Maybe cam seals if at front of engine.
head gaskets shouldnt cost much. Pretty sure you can leave timing belt on and drop the belt tension with special long bolt. And just undo cam gears off the cams and leave them there.
vky2g is having same issues at present and is chasing a used gasket to model a new composite hg from.
but i think (k?) That the sohc hg will fit fine. If you wanted a composite. I have a mls that came in a gasket kit from kerzan in nz.

check for valve leaks while head is off (splash of kero in the ports) and check block/head is flat so you know if you need to machine it.
Mls and composite gaskets should be machined differently. Mls requires smoother finish.
i think a composite should do you fine.

um..may as well put some arp head studs in while in there. 3sgte ones fit (thanks brian)

really only one spot in the gasket that has oil pressure through it. On the 63 its the gearbox end, on exhaust corner head bolt. This is the feed up to the head/cams/turbo etc. I think the 93 is same spot. If its leaking from a different position, it may not be hg.

 

[4piknup]

Just seen pic.

you need to pull front timing cover off, clean it all up, poke balancer back on and run it without timing cover. Then find leak.

im guessing cam seals. If its crank, i have a speedy sleeve if the crank is grooved bad.

 

[4piknup]

It will be leak8ng onto a turning shaft (cam or crank) and flinging onto everything else from there. It will be pooling above where you see the leak and dripping through.

 

[khubner1]

as above degrease it pull the timing cover get that thing spotless then run it and look for the leak it's impossible to diagnose an oil leak when the whole thing is covered in oil.

4g93 sohc gaskets fit for composite there are also mls options out there

 

[mathew_colville]

so the oil was coming from the cam seals, some of the bolts where loose on the oil sump and the turbo drain pipe (not sure of the correct name) but it all seems to be ok at the moment

 

[evo-gsr]

For now ^ !
Bloody things are notorious for leaks....the constant heat doesnt help much I suppose.

 

[mathew_colville]

That doesn't fill me with much confidence [emoji37] lol

 

[4piknup]

Talking about the turbo drain. The rest will be ok, as long as you have good cylinder compression

 

[mathew_colville]

oh ok thats a relief, i can deal with that

 

[khubner1]

only way i've found to stop it leaking is to
1 ensure that the gasket area is clean
2 cover entire gasket area in rtv
3 use nylon style washers again covered in rtv

 

[mathew_colville]

ok thanks :thumbsup:

 

[4piknup]

Mine leaks out from between the concertina joins on the pipe itself. Not sure if there is a inner liner that has desintegrated or what.

 

[khubner1]

Mine leaks out from between the concertina joins on the pipe itself. Not sure if there is a inner liner that has desintegrated or what.

the above assumes the pipe isn't damaged or leaking

 

[mathew_colville]

Im still having trouble with oil leaks at the front of the engine, i have no idea where its coming from, im just wondering if anyone has used one of those uv dyes to trace the leak, are they any good, will they damage my engine and is there anywhere in australia you can buy it?

 

[EVO-00X]

Chances are its the timing case mate. They will leak with age and perhaps it may even have a crack in it.
To get to it properly you basically have to remove the engine anyway.
Do it properly, or you can be chasing your tail for ages spending more time and effort on it. If its putting oil on your timing belt, that needs replacing too.
Take the engine out, get in there and replace the gaskets, seals and waterpump, plus timing belt. Do a little bit of a service and it'll be maintenance free there for another 10+ years.