Mitsi Gto head problem

[Graeme Stebbing]

Hi Guys, i realize its not a gt40 but i need your expert opinions really bad, my Gto TT needed a new waterpump so i replaced it no problem been there before not a major, refitted timing belt correctly, turned over several revs by hand no problem, turned over by starter with plugs out all ok, went away for a few days reassembled all the extras like intake manifold plugs etc,turned over on the starter and it stopped after a few turns and was jammed solid, crank would only turn over about 60 deg, looked in plug holes all seemed fine, then i thought maybe it got some water down the intercooler while i was away and had hydrolocked, thinking bent rods etc not a good day, dropped the pan rods are fine, so pulled the front head, still locked solid until i loosened off the rear head and then it turned over fine, removed the rear head and expected to find a dropped bolt or something but nothing in the bores, except lots of loose carbon around the lip of the bore and lip of all the pistons, in both heads, and about 3 mil thick behind the squich area beside the exhaust valves, friend recons it was because of excessive towing weight recently lasting a few weeks moving house etc, that caused all the carbon, i did find a leaking turbo intake seal sending oil through the motor, but i use Mobil 1 so i ruled that out, its not supposed to leave a residue, but really need help bad as its my daily driver. Also can i reuse the metal head gasket that it has, it's 3 layers of shim like metal with no paper in it all, any help much appreciated.
Graeme

 

[Will Campbell]

This is surely a major contender for a World Record run-on sentence. I got dizzy half-way into it.

 

[Ron Earp]

still locked solid until i loosened off the rear head and then it turned over fine, removed the rear head and expected to find a dropped bolt or something but nothing in the bores,

"Until I removed the rear head the engine was locked solid."

I suspect if you look carefully at the pistons that were under that head you'll find one of them has the good ol telltale imprint of a valve edge. And, if you look carefully at the head you'l find a valve or valves that are bent, thus, the piston/valve interference had locked the engine up.

 

[Woody]

Graeme
Like Ron said you need to check your valves.
Regardless of the type of oil ,if the turbo inlet seal is leaking its a problem that needs fixing. You can usualy find traces of oil in the intake manifold and the carbon in the head will be wet and sticky. You could tow your house to the new address and it wouldn't cause that.
As for reusing the head gaskets definitely not recommended.
Woody

 

[Graeme Stebbing]

Thanks guys for all the suggestions, i did strip this motor about 5 years ago to find out why it always used water, and found cracks in the heads between the cylinders to the water jacket that some clever person in Japan had welded up and then ground off the welds, not the brightest.
The old heads were unusable so i fitted heads from a Diamonte they measured up the same, i swapped my turbo valves into it, fitted new valve seals, gave it a valve grind, ,and a general clean out there was carbon just the same as any other motor i have ever stripped but not as much as i have now. The diamonte i pulled the heads from had done 80k and the heads were like new no carbon at all bright aluminium only tinted pink from the petrol, i suspect my motor may have a bit of blow by ,but it never blows any smoke and uses about a litre per 1000-1500 k which could be the turbo problem,so not too bad for a 20yo motor thats not been reconditioned. i do have a replacement rear turbo i can fit, the front shows no signs of an oil problem.
The strange thing was that after the rebuild last time the engine started using water again about a year later, and it never ran out on the ground, but recently, i went to top it up and as fast as i poured it in it just ran out, i tracked the leak to the wings on the water pump where they joined the block, maybe it was loosened bolts so this time it will get locktighted up. Another friend suggested maybe it was running very rich, and that it could be the o2 sensor but the car does 30 mpg on a run so i ruled out that is running rich. So really puzzled why i have so much carbon.Maybe because i drive it like grandma lol, my son says i need to drive it harder, but then i could't afford the speeding fines. Maybe cheaper to try the seafoam, as i don't need to have to strip this motor again, its a major to get apart.
Also whats the best way to check the valves, pull them, and spin in a lathe, they look fine in the head and with the cams installed they moved smoothley no binding etc
and no signs of them hitting the pistons at all
Best regards
Graeme

 

[BruceA]

Hi Graeme. Have you got the workshop set up yet? Might it be cheaper to grab a second hand engine and just pop that in instead? Specially if the heads are starting to turn into a problem.

 

[Graeme Stebbing]

Hi Bruce, No shed is on hold, got the ground levelled out by a neighbour who stuffed it up had to pay a pro to fix the mess the neighbour made of it.i am fixing the car out in the open between the showers, who ever called Northland the winterless north was cleary delusional lol, i had a good ring around the wreckers/importers etc, there is nothing available out there, nobody has imported a used GTO TT motor for at least 10 years so have to make the best of what i have.
i have a couple of spare turbos so will throw a replacement on to hopefully cure the rear ones oil problem, and see how that goes.
The biggest problem is when you pull apart a 20 yr old car you also find all the other things that or on the way out, and given my location the main parts suppiers are in Auckland, so lots of trips to the big smoke.
If you do get down this way do drop in, also i would love to come see your CT baby once my wheels are sorted out.
Regards
Graeme