compression loss
 

i bought my 1989 supra and was told it ran but doesnt hold compression in 2 cylinders i am hopeing its just a head gasket any ideas

Headgasket, Valves bent/broke, Rings beat, Broken piston...Could be lots of stuff. I bet its the headgasket tho. Do a leakdown test, And see how fast it goes. If its really fast, Probably a broken metal part. I wouldnt run the car like this. Probably fragments in the cylinders, and that is not good! I got a spring in my gokart motor once, Ill show you a picture of it later what it did lol.

ive seen dismembered engines where stuff has gotten into the cylinders..GAME OVER for that engine. u can see the imprint of where the piston head hit the object or watever was in it. ive seen half of a screw indented into an engines piston. and ive also seen water damage to pistons. the whole rod was snapped because water got into the cylinder and couldnt combust so the rod has too much pressure oushing back on it as it was thrusting and it snapped. crazzzy stuff.

how do u do a leak down test??

A leak down test puts air into the cylinder then the guage shows if there is a pressure loss and if so, how much pressure is lost during a set time. All cylinders are going to leak some though. You can sometimes hear the air escaping through various parts though. Through the intake then probably an intake valve and same with the exhaust. If you can hear air coming through the oil filler cap then it is most likely worn out rings, if you get bubbling in the radiator, well that pretty much shows a gasket problem and if you can hear air coming out the sparkplug hole next to the pressurized one then it is again the gasket.

I'm sure more out there have more info, but probably a shop that you trust and would let you see what's going on would be best as the guages might be expensive.

Russ

Yeah, Its a good idea to let a pro do it. But you can get a compression tester, thats pretty easy to use.