Massey Discussion Forums > Massey Talk > bubbles in the coolant
Order posts by: 

bubbles in the coolant

Greetings all

I bought a 555 gas tractor that I am going to attempt to restore. I am doing some checks to see what is all broken on it before I start to take it apart. I fired it up and was looking at the coolant rising up in the radiator and noticed a steady trickle of small bubbles. The engine runs great. Doesn't smoke except a puff on a cold startup. No oil in the coolant, No coolant in the oil (cracked the oil pan drain plug before starting it). Oil pressure steady between 20 and 22 psi. The bubbles in the coolant are a bit concerning. I am not a mechanic but am somewhat mechanically inclined.  I do not really relish the thought of tearing too deep into this engine if I don't have to. I am restoring it for show not to work. I wonder if i might get some opinions on this matter

Thanks 

John

ps: What does "Subscribe to Post" mean?

RE:bubbles in the coolant

Sounds like it could be a blown head gasket
Steve

RE:bubbles in the coolant

John,

First of all Welcome to the MCA site I see you are our newest member, thanks for joining we may learn from you just as much as you can learn from us.

Now to the 555 bubble problem, is it actually making bubbles or is it just the coolant passing through so fast it looks like bubbles? If it is truly bubbles coming from a head gasket it should build pressure very fast. If you have the radiator cap on does it build pressure and blow out the overflow pipe? If not I wouldn't worry about it. You said there was no oil in the coolant and no coolant in the oil so I have a hard time believing you even have a problem at all. If the head gasket was leaking It would most likely fill up one of the cylinders with coolant when it sits for a period of time as it would seep past the bad gasket but you would notice this very quickly when you try to start it as it would more than likely hydro lock.

The "Subscribe to Post" you were wondering about, If you click on it to subscribe to the post it will send you an email when someone responds to that post. I don't know if it actually works as I have never subscribed to any posts, I usually just check the page a couple times a day.

Joe

RE:bubbles in the coolant

Thanks kindly for the reply Joe.

No It's definately small bubbles. I think I over filled the system the first time. I filled it darned near up to the flange where the cap seats (was slow to realize that the system didn't have an overflow tank). I fired it up and very shortly thereafter it started coming out of the overflow. After thinking about it for a while I figured that I had just probably over filled it but decided for heck of it to check for another reason that the tractor might be pushing the coolant out. i was able to watch the coolant as it rose for a minute or so. The cap gasket looks pretty ratty and it isn't bonded to the cap. It's sitting loose in the neck of the radiator. Is the gasket separate on these tractors or integral with the cap?

I've had the tractor in storage for a couple of years since I bought it. When I've checked on it a few times I've noticed that the hoses are cracked. one of the frost plugs is weeping and I cant be sure but I think there also might be a pin hole in the bottom of the top radiator tank. I do'nt know if any of this would be related to the bubbles issue or not

Thanks again 

John

RE:bubbles in the coolant

Oh and I should clarify that the rad cap was installed when it pushed out the coolant.

RE:bubbles in the coolant

John,

It really sounds like a head gasket issue to me.  In fact, hopefully it is the head gasket and not a crack somewhere.  You could have either one and not get coolant in the oil, or vice-versa.

If you want to try to get really clever before pulling your cylinder head, you could take an old radiator cap and braze a tube to it.  Then run a hose from that tube into a bucket of water.  Run the tractor.  If you get continuous bubbles, the you are getting combustion gas in your coolant.

Sounds like you are going to have to pull your cylinder head at a minimum.  With luck, you can just replace the head gasket, and not have to have the top deck of the cylinder block and/or the head deck planed.

Good luck.  Keep us posted.

JB