Hilux 4x4 Forum

hello everyone, planning on rebuilding the cylinder head on my 2L engine for my hilux, its leaking really badly from the back of the engine, i think previously the cylinder head was not torqued to the correct spec. Is there anything i should put on the engine block or cylinder head before fitting the head gasket, ive heard that some people put grease , oil or shellac . Or should i just fit it on a clean engine block, no chemicals. any other pips and tricks for this lengthy procedure ? thank you!!!

The best is to fit a good quality gasket to clean surfaces. If the mating surfaces have been scoured for some reason, leaving scratches or if there is minor pitting from corrosion (deep pitting is another problem), then it might be advisable to use some form of gasket cement. The problem with using these products is that subsequent gasket removal becomes a bit of a mission. Using an aluminium paint (non bituminous) on the mating surfaces immediately prior to assembly works quite well in place of gasket cements.

ok ill only know once I've removed the cylinder head tomorrow, if its all smooth then will fit it with no cement etc, thanks !!

When you have the head off, make sure to check that the head and block mating surfaces are level and flat. Use a steel rule across the surface and check for gaps.

A warped head can cause the same thing so check carefully and if you find any gap have the head skimmed flat.

Sent from my SM-G955F using Tapatalk

ALUMINIUM SPRAY AND INCREASE TORQUE SETTINGS WITH 10NM

ok cool i checked that, they are flat , would copper spray do the same job ? mind you its a paper type head gasket and has a coating of like grey rubber on it

Deciced to remove the bonnet makes things abit easier if you climb in , the exhaust valves had heaps of carbon/gunk on them, piston 4s was the worst, is this normal(managed to clean them up with a bench grinder and scraper)? On the pic of the cylinder head you can see where the head gasket failed where there's oil. Compared to all 4 of the pistons piston 3 had the most soot on it, pistons are not shaking so rings must be ok. however once i cleaned off the old gasket material the side where the head gasket was leaking turned out to have some pitting hoping it seals well.

Hmmmm ..... that pitting around the water galleries doesn't look too wonderful. The aluminium paint will certainly help but I think a light skim of the head would be in order. I'm not one for unnecessary skimming, however in your case it might be recommended - it will also eliminate any warping issues that may be present.

ok, its been skimmed before, i think there's a minimum thickness the cylinder head has to be, will try and research what the minimum amount is and get it skimmed hopefully, thanks for the help!

Hopefully just a light skim will do it.

The question you need to ask yourself is if you want to be doing this all over again in a year or two. If it lasts that long. I always say that seeing as I have done the work it does not make sense if you do not do it properly. A good engineering shop will immediately be able to tell you if the head can still be skimmed.

true!ill do that thanks, yup cleaning each and every component is a pain!