2XR95Z28

iTrader: (4)

Hey i was wondering if there was anyway to check for a blown head gasket without having to take off the head? I just picked up my car from having a few minor issused fixed, and my neighbor the shop owner noticed it was smoking alot and thought it may be a head gasket. I was wondering how i can test for a blown gasket if there is anyway without taking the head off?

Thanks!

2XR95Z28

iTrader: (4)

anyone?

impaled

compresssion test for sure. unusually low compression (>20% off of top) in one cylinder or two adjacent cylinders would be a sure sign.

leakdown would be even better, but by far more demanding. i think compression test would be sufficient plus the signs below...

oil in coolent - can get coolant tested for hydrocarbons

coolent in oil (looks like a milkshake) because of the bubbles.

riceburnerZ28

iTrader: (20)

yea everything he said ^^^^^ !

2XR95Z28

iTrader: (4)

I heard that if you take out a spark plug and give the motor a little crank and coolant comes out the plug hole then it's a blown head gasket? That true?

impaled

yes it is true, but that would have to be a major leak, and it would have to be in the cylinder(s) in which the head gasket is cracked.

best off doing it the right way and compression test it and look at the oil and coolent.

MTBSully

iTrader: (7)

compression test or leakdown test

2XR95Z28

iTrader: (4)

Alright, i'm gonna check the oil tomorrow, its brand new oil with prolly less than 100 miles, if it is still good is it alright to re-use or not?

2XR95Z28

iTrader: (4)

Alright so i topped off my coolant today and let it run for about 15 mins at idle, i would say within about 8-10 mins the temp gauge was up to about 200 so i hit the fans and within a min it dropped back down to a little above 180. there was some white smoke coming from the pipes, but it also was in my garage with the door part open and its like 45* and raining outside so i'm not sure if its just the cold making it smoke?

Also anyone on the oil? its brand new mobil1 and would like to try to stay away from havein to put new oil in already. Dip stick looks good, no obvious signs of coolant on there at all.

2XR95Z28

iTrader: (4)

? confused by what u mean

jarretthise

iTrader: (9)

dude its a blown head gasket....what you can do is take all your plugs out and do a compression test....or if its bad enough when you crank it you can put your finger over the spark plug hole and it will blow out of the next one

MTBSully

iTrader: (7)

i disagree. ALL LT1's are going to smoke alot if its cold and wet. Heres my 95 formula last winter when it was 35 and raining. If the car is overheating when your driving down the road, you have a problem. If it runs to 200, fans kick in and it comes back down, thats normal. Just don't ever let it hit the red and you should be fine.

Don't do a head gasket if you don't have to.

jarretthise

iTrader: (9)

and no dont go using the same oil....just put friesh in it

MTBSully

iTrader: (7)

also if there is coolant in your oil you should clearly be able to see a mustard/milkshake liquid on your dipstick.

2XR95Z28

iTrader: (4)

drained the oil and there are no signs of milkyness whatsoever. I'm thinkin its a rainy cold day and any car is going to smoke a little from the condensation in the air. Only thing concerning me is i was about 2/3 a gallon low on coolant. Now i dont remember the last time i checked it, but it shouldn't matter should it? Next test is just a compression test correct? Anything else i can do?

jarretthise

iTrader: (9)

nope thats really it unless you want to pull of your heads and find out haha

2XR95Z28

iTrader: (4)

thats what i thought haha, I've also heard that after drivin the car around a little and gettin it to temp then parking it at idle and listenin for coolant boiling back into the overflow is another sign? true?

impaled

just bit the bullet and compression test it. and know for sure (or at least have a better idea).

draining the oil and replacing it at this point was just a waste of oil if it didnt have coolent in it (milkshake, bubbles, etc.)

if compression checks out fine and you still have coolent loss (unlikely unless you have a bad hose), check coolant for hydrocarbons. that is a sure sign.

2XR95Z28

iTrader: (4)

Alright i think i'm gonna get some headers ordered and compression test it while i'm doing those. I figure while i'm workin up in there mise well put some headers in there. When i do make a compression test what should the compression be in all cylinders? i've never performed a test so just trying to get a little heads up. Also i have to take out all the plugs and test each one or how do i go about doing that?

SLawson86

iTrader: (8)

cant really give you a minimum reading, but check all of them. take the highest reading and verify they are within 10%-15% of the highest cylinder