Blown Head Gasket Quest.

[DFG 5OH]

Well my mechanic was too busy to check to see if my car has a blown head gasket, so he gave me a tool to check on my own, and my being the aspiring do-it-your-selfer I am, I was up to the challenge. As most of you know I have been having bad timing problems, and I just wanted to rule out, or in, the possibility of a blown head gasket.

The other day it was warmer than it has been outside, and my car was pinging really bad. I did a couple WOT runs, and noticed white puffs of smoke out the back of the car. Well I checked the obvious, and the oil was not milkey. I did have a low antifreeze problem, and I ran some stop-leak through the rad. and it seemed to clear it up. I also leak/burn a lot of oil between changes (3000 miles)

So back to the story, I've been out in the garage with this tool. it is a 1' long hose. One end has threads to go in the spark plug hole, one end has a quick coupling for an air hose. You screw it into where the spark plug would go, and put about 100 lbs of pressure on the hose. You're suppost to watch the rad. fluid with the cap off, and if you see bubbles, then thats a for sure sign that you've got a blown head gasket. Well so car I've checked the whole drivers side, and 2/4 were fine, the other 2 would not hold pressure. I didnt see bubbles in the rad, but i could hear the air leaking out somewhere inside the engine. Could it be that maybe my rings are bad. Keep in mind that all the plulgs i pulled look pretty good, I can post a pic if neseccary, but I didnt think it was because they look fine.

So I'm not real sure what i'm asking, but any input will help.

 

[Killercanary]

SOunds like the valves on those cylinders were open to me. You should make sure that when you test each cylinder that the valves are both closed.

 

[DFG 5OH]

SOunds like the valves on those cylinders were open to me. You should make sure that when you test each cylinder that the valves are both closed.

i thought of that, but i dont know how to check...

 

[Killercanary]

Easiest way is to remove the spark plug and have someone rotate the engine while you stick your finger in the psark plug hole. You will feel it either sucking air in past your finger or trying to blow your finger out of the hole. When you feel the air coming out of the hole that is your compression stroke and both valves are closed. Test that cylinder then.

Edit, you don't actually stick your finger in the hole, but rather competely block the spark plug hole off with it so you will feel if there is a vacuum or pressure.

 

[mytight95]

better yet thread the hose in without hooking the air hose to it, and do what paul stated and wait for it to start pushing air out the hose..... kinda hard to cover the entire plug hose with a finger etc. dep. on what heads you have......

good luck, hope you don't have a bad gasket...


jason

 

[Zero Signal]

If you are running lean, there is the possibility of burning the exhuast valves. That combined with old valve spring and you may find that the valve seat itself might not seal very well. And of course it could just be a gasket.

 

[DFG 5OH]

i know the engine could be pretty tired and worn out after 144K on it, but its SUPPOSTST to be highway driven/adult driven...ect. not that adults dont drive hard...i'm the third owner, the first was an old lady, the second was a middle age guy, who drove it on the highway to work and needed something better for gas...i do drive it hard occasionally, but for the most part i drive pretty conservativly.

 

[CManT1914]

Matt, I really doubt you have a blown HG. That's something that's usually REALLY noticeable! Oh, and never use that stop leak again!! We've had cars come into the dealership where people put that stuff in, and it's a nightmare! Back in the day, radiators had real wide runners, and stop leak was okay. Nowadays, the runners are thinner, so that stop leak is more likely to build up and block the radiator up. Trust me! I would NEVER use that or recommend it to anyone. Back on topic, you could also do a compression test to determine what cylinders have good compression. The test your mechanic recommended is a leak-down test, basically tells you the same thing, but a compression test is easier (IMHO).

 

[DFG 5OH]

i did a compression test back before i had the timing fixed, and all cylinders came up 150psi or more.