Head Gaskets?

[Mephisto]

Re: Head Gaskets?

I am no expert on this subject. But I will post what my thoughts are. And they may be totally wrong.

My thinking is if you are getting 0 compression that you would have a hole in your piston. I don't know if possibly a head gasket blown out say to the outside of the engine from cylinder 1 and 2 could cause a 0 compression reading or not. I have never had this issue. But I would think if this happened you would have coolant/oil flowing from this spot.

I would think if you have a head gasket blow out between cylinders. I would think you would get a compression reading. But they may be a lower reading. And both of those readings would be almost the same compression reading.

Again this is just my thoughts so I could be totally wrong.

That makes sense... but wouldn't there have been a loud noise or some obvious indication that I had put a hole through a cylinder?

Also as a point of reference, the oil looks normal, smells fine, and doesn't show any indication of water/coolant mixing into it.

The few people I've talked to outside of this site all seemed to think it's the head gaskets... but, we could all be wrong too.

PS, sorry for totally hijacking this thread, but I do have a Saudi Ty... so...:rotf:

 

[Ls10]

Re: Head Gaskets?

Pop the valve cover and check valve train to rule out a stuck couple valves.

 

[wildphil]

Re: Head Gaskets?

Pop the valve cover and check valve train to rule out a stuck couple valves.

I guess that could be possible if a valve on each of those two cylinders is staying open for some reason. I didn't think of that type of issue.

 

[Don W.]

Re: Head Gaskets?

0 compression on 1 & 2 is a bit weird. It might be the best bet, instead of guessing, would be to just pull the heads and see what you find.

Just FYI you can't "refill" the radiator through the header tank. You have to use the cap itself. If it's pushing water out then it's either a blown head gasket or a crack somewhere. Refill the rad, leave the cap off, start it and see if it pushes water out. My guess is it will so you're back to pulling the heads. You say the oil is clean. If that so and it's not suddenly using a ton of oil then the bottom end might be OK.

 

[Mephisto]

Re: Head Gaskets?

Just FYI you can't "refill" the radiator through the header tank. You have to use the cap itself. If it's pushing water out then it's either a blown head gasket or a crack somewhere. Refill the rad, leave the cap off, start it and see if it pushes water out. My guess is it will so you're back to pulling the heads.

Not to sound thick, but if the coolant from the overflow tank doesn't go back into the radiator, then where's it going? Initially i thought because the motor had been sitting for some time that maybe some of the veins in the block were clogged up and were eventually working themselves out (when i opened the petcock valve to flush out the system, a lot of rusty fluid came out). But every time I topped off the overflow tank, I'd go drive the truck 20mi, come home and the overflow tank was completely empty. So couple that with the exhaust smelling like coolant, I figured I was burning through all the coolant... again, I could be completely wrong here.

 

[Adam#0213]

Re: Head Gaskets?

Not to sound thick, but if the coolant from the overflow tank doesn't go back into the radiator, then where's it going? Initially i thought because the motor had been sitting for some time that maybe some of the veins in the block were clogged up and were eventually working themselves out (when i opened the petcock valve to flush out the system, a lot of rusty fluid came out). But every time I topped off the overflow tank, I'd go drive the truck 20mi, come home and the overflow tank was completely empty. So couple that with the exhaust smelling like coolant, I figured I was burning through all the coolant... again, I could be completely wrong here.

What does your oil look like?if coolant is present then your oil cap would be showing moisture on the inside of cap at least that is what I would think

 

[liquidswords88]

Re: Head Gaskets?

If you have zero compression in two cylinders, your oil CANNOT be "normal". It would be thin and full of gas.
I have much more experience with 2 stroke engines than 4 stroke, but I have burnt holes dead center of Pistons numerous times in snowmobiles. Running them a touch too lean for extended periods does it. There was nothing dramatic about it, a small poof then no power.

 

[Mephisto]

Re: Head Gaskets?

What does your oil look like?if coolant is present then your oil cap would be showing moisture on the inside of cap at least that is what I would think

Oil is clean... no signs of it mixing with coolant/water, and doesn't smell burnt.

 

[Don W.]

Re: Head Gaskets?

Not to sound thick, but if the coolant from the overflow tank doesn't go back into the radiator, then where's it going? Initially i thought because the motor had been sitting for some time that maybe some of the veins in the block were clogged up and were eventually working themselves out (when i opened the petcock valve to flush out the system, a lot of rusty fluid came out). But every time I topped off the overflow tank, I'd go drive the truck 20mi, come home and the overflow tank was completely empty. So couple that with the exhaust smelling like coolant, I figured I was burning through all the coolant... again, I could be completely wrong here.

Well it goes into the rad of course but it has to go through that small hose and then past the vac break in the cap which is usually held closed with a light spring and there is no force or pressure coming from the header tank water to open that valve.

The header tank works on the siphon principal. Normally the rad is full and cold and there is water in the header tank. As the motor heats up and the water expands some goes past the cap into the header tank. (Just look at the tank cold and again with the motor hot.) As the motor cools a slight vac occurs and water siphons back into the rad from the tank keeping the rad itself completely full at all times.

I'm sure there are other ways but the only way I've found to completely fill the rad and have the header tank work as above is to fill the rad, warm the engine until the t-stat opens, top of the rad then let it sit until cool. Top off the rad once more along with the header tank (usually about half full) and I'm good to go. Works every time. For me anyway...:roll:

HTH

If you're loosing water then there is a problem somewhere. The issue becomes where.

 

[wildphil]

Re: Head Gaskets?

And if you can smell it at your exhaust. You will never forget the smell once you smell it. Kind of a odd sweet smell along with a little coolant smell. You know it is coming from the heads.

If your oil looks normal. No milky color to it. It is not getting in your engine oil.

 

[Mephisto]

Re: Head Gaskets?

I'm gonna pull the cover off this POS on saturday and start it up... it's been at least a year since it's even been started. I'll let it run a bit and check the oil again to see if it smells like gas. I'll top off the radiator as well and see what happens there.

I saw a video on youtube that said to pull all the spark plugs, remove the radiator cap, top off the radiator, then replace the spark plug one cylinder at a time, and hit the ignition... if coolant starts bubbling out of the radiator, that means the head gasket is blown on that cylinder and the compression from that cylinder is pushing air into the water jacket forcing it out through the radiator? Not sure how legit that method is, but it is something else to try to help narrow down the actual problem, aside from "my exhaust is blowing steam and smells like coolant".

Anytime I start googling about this problem, I feel like I'm going on WebMD and self diagnosing myself before going to the doctor, only to have him tell me "no dude, that's not what's wrong... stop reading shit on the web.".:lol:

 

[Mephisto]

Re: Head Gaskets?

Started it up this morning... and well this probably isn't optimum... checked the oil out too, and contrary to my earlier statement, oil still looks ok, but does smell like gas.

I also did that silly "paper test" at the exhaust pipe which allegedly tells you if you have a valve stuck open... and it sucked the paper right up and ripped a hole in it.

 

[Joegoodlb]

Re: Head Gaskets?

Proper tune plays a big part too