My mate has just got a hold of an 89, Twin Turbo, J-Spec, auto.

Been sitting a wee while, but appears to start and run quite evenly.

 

Done a compression test to start off and these are the results.

Test done with engine warmed up and all spark-plugs removed.

 

 

Dry test was

 

Cylinder 1 : 150psi. Cylinder 2 : 150psi

Cylinder 3 : 145psi Cylinder 4 : 150psi

Cylinder 5 : 120psi Cylinder 6 : 150psi

 

Wet test was

 

Cylinder 1 : 165psi Cylinder 2 : 180psi

Cylinder 3 : 145psi Cylinder 4 : 180psi

Cylinder 5 : 140psi Cylinder 6 : 180psi

 

Any recommendations as to whether to splash out on a rebuild, or just change the timing belt, tensioner etc and a good service.

Will probably pull the engine as he has a couple of turbos lined up anyways, but would it be worthwhile doing anything else, or do the readings sound ok ?

He has no mad power gains planned, just looking for a reliable Zed.

 

Cheers,

 

Alan.............

number 5 is obviously the weak one and the ring is letting gasses through but ive seen lower, i would run it until it goes, you could get a month, you could get years out of it like that

 

Mike

number 5 is obviously the weak one and the ring is letting gasses through but ive seen lower, i would run it until it goes, you could get a month, you could get years out of it like that

 

Mike

 

So as a stop gap, maybe mot it, tax it and run it a while, then depending on how it goes, or doesnt, make a decision from there ?

 

Alan..................

According to the service manual

 

it's 14 psi between cylinders

standard 186 psi

lowest 142 psi

 

Sound like piston ring wear all round and a problem with the left hand bank with either valve damage or a leak somewhere on the head gasket.

 

The engine is a little tired but if your not bothered about out and out performance then it'll probably run for years like that! One of those see how it goes like kirbz says if your not desperate.