racer02GTstang

well... all was seeming fine till i got to cylinder numbers 3 and 5.... i think the headgasket is internally blown on the driver side because each one of those cylinders put out 78 and 90 psi while all others were from 125-150... remember i do have 18cc dished pistons... so its lower than most motors.


oh also... all my other plugs were looking alot better... those 2 had alot of carbon build up..

oxfordgt

Is this a new motor?

racer02GTstang

2300 miles on her.

racer02GTstang

what still makes me think are the plugs are looking good.. just alittle rich... no loss in coolant...

what if say i have a sticking valve and its not fully shutting from all that carbon being in those 2 cylinders?

oxfordgt

If you had a blown head gasket it would be cylinders right next to each other with low compression. How often did you change your oil during break in? How many miles did you put on it before you put on the blower? How many miles before you romped on it?

racer02GTstang

i changed the oil at 100 miles, 500 miles, and 950 miles... the blower went on at about 1000 miles... i started romping on it around 1500 miles and this problem occured around 2000 miles.

and yes, these cylinders are side by side.. they are the 2 middle ones on the driver side. and i thought they were cylinders 3 and 5 but i may be wrong.

oxfordgt

Those would be 6 and 7 then. Well I hope you just have a blown head gasket then. Got any smoke coming out of the exhaust? Do you know how to do a leak down test?

racer02GTstang

no, whats a leak down test??

it puts out alittle white on start up but then it runs fine with no smoke... sometimes alittle black in the upper rpms.

oxfordgt

You need to turn the crank so that that both valves in that cylinder are closed. Then use the compression test hose and install it in the spark plug hole. You need to have an air compressor and fill the cylinder with air.

If you hear the air leaking out of the:
exhaust = bent exhaust valve or bad seat
intake = bent intake valve or bad seat
pcv = scratched cylinder wall or bad rings
adjacent sparkplug hole = blown head gasket

Lets hope for the last one since it is the easiset fix.

racer02GTstang

well... im ordering the headgasket thursday so i should have it mid next week.. which i will be florida at the time but the week after i get back... my first day off im puttin the new gasket in and gettin my baby back... all ready for another break in period for that gasket. haha.