Head Gasket

[StuMiller]

Hi all,

First post this year...hope everyone had a fantastic Christmas and a safe one!!

For those of you who didn't drink copious amounts of grog and can remember, I posted last year that I was having an hell of time starting my 99 ZX6 track bike.

Anyway, I took it to people who know stuff and the end result was a faulty fuel pump relay assembly. A quick and cheap fix and all is well.

The bike is now at home and ready for a track day. I started it tonight and it sounds like it's running on three cylinders. The oil in the sightglass has a milky white residue, so due to previous members thoughts on me having done a head gasket, does it now sound more like the gasket has gone?

If so, what would I expect to pay for the repair?

Anyway, all feedback welcome!

Cheers!

[mike-s]

Ultimate test is doing a compression test (wet & dry). Remember though that if there's a slight milky colour which goes away when fully warmed up that's ok, as it's just a bit of moisture, if it's a veritable milkshake then it may not be so good. Have you also checked the water pump to make sure that's not causing grief too?

Head gasket is pretty easy to do yourself if your mechanically inclined.
Bodywork off,
drain radiator then oil (especially as yours has crapped out) and oil filter
remove carbs/efi and exhaust
take plumbing off engine
rocker cover off,
nip the camchain tensioner in place so it doesn't spoing every freaking where when removed, then remove it
undo the bolts holding the cams in place
tie something around the camchain so that it doesn't vanish down the void between the barrels and the head.
remove cams & any bits that will fall out, like shims (making sure to note which cylinder & valve they go onto)
crack open the nuts on the studs holding the head down, making sure you don't loose them or the washer down the void.
take head off
look at old head gasket in dismay
clean both surfaces as much as you can using a brass tooth brush (steel is harder than aluminium, brass is a lot closer match and should minimise damage) and degreaser to remove any scorch marks, etc.
Use the edge of a metal ruler across the barrels and the head diagonally to see if there is any warping / if the head/barrels need to be decked.
Assuming nothing goes wrong with the head or barrels commence re-assembly which is roughly the reverse of this, just remember to have the know how or manual on torque settings & setting the timing.

I'm halfway through doing this on my 250, the valves are being a p.o.s. so am halfway through tracking down another head/engine.

[StuMiller]

Just talking to a mechanic down here in Hobart; considering my bike has only done 38 000kms, he thinks it's probably not the head gasket. He suggested it might be the water pump seal.....

How can I check this without having to strip the bike down too far.....

[mike-s]

Plastic off on left side lowers (i think that's where the pump is). Drain coolant and possibly oil (not sure if pump is below oil line or not). Take hose off front of pump, you'll soon see if it has any blades damaged (which certainly means pump removal/repair/replacement). Remove any extras in the way of the pump (usually things like the clutch master cylinder) and undo any securing bolts for pump to engine, it should just slide out. At this point you might as well just replace the oil seal and be done with it .

At least that's how it worked on yee olde gpx750.

[DaveGPz]

I started it tonight and it sounds like it's running on three cylinders.

You get used to it !

[robracer]

clean both surfaces as much as you can using a brass tooth brush (steel is harder than aluminium, brass is a lot closer match and should minimise damage)

Mike that is the hard way, get a can of Permatex from supacheep spray or brush on 10 minuites later the gasket just falls off leaving a perfect surface for the new gasket

[mike-s]

Shit, i forgot i had a can of this stuff in the garage.

I'm freaking being serious!