Honeycomb Radiator Belch

[Gary 30U]

One of those problems that won't go away.

When I started driving my 30U I had what I first thought was an overheating problem. I could drive the car for about 10 or 15 minutes and the radiator would just belch coolant out the cap and all over the engine and body. When I would go to put more water in it (stop at the service station) you could take the cap off and look inside to see the circulation of the coolant. It was NOT hot, even to the touch. I put more water in and it just did the same thing over and over again.

I was told that I should leave the water level down to just above the tubes, as that is the normal level it seeks. Didn't seem to help.

I took the water pump off and had it rebuilt. Still no help.

At one point I noted that the water level was down below the level of the internal tubes and there appeared to be quite a bit of rust on the top of the tubes. Hey, I had found the problem. I ran some radiator cleaner throught the engine (twice just to make sure) and thought that would solve the problem. NOT. Things proceeded as before. No rust showing, but still the belching.

The water pump didn't sound good and I had it rebuilt again. There is lots of circulation in the system, but still no help.

I then thought maybe there could be a stuck thermostat. I didn't think so because of the constant circulation but at least I took a look. Removed the hose connector from the top of the head and as I thought there was no thermostat at all.

At one point I thought that it might be a coolant isssue and tried it with just plain water. Still no change. The other day I drove it to the club meeting, about 15 miles in 75 degree heat and no problem. On the way home that evening in 65 degree weather it did it twice.

If anyone has had this problem, or any ideas on how to correct it please advise. I am going to pull the engine this winter to check for vibration and balance issues and would like to solve this problem at the same time.

Thanks,
Gary

[Rusty]

I had/have the same problem with my 29 but I have no water pump.  Have you check the rad out by a shop.  I had mine checked twice and still no luck and then sent it off to brass works to have new core.  They emailed me once it arrived and said it was bad.  What they told be was shops check the flow against current rad standards.  They have to be pretty clear in order to work.  They do make a core in honeycomb which is pricely, I went with a modern type with the orginal top/bottom tanks.  I wanted a driver over show orginially, just me.  I would bet your water pump is not as good as any modern car would have.

Other ideas is your timing is very retarded or your exhasut pipe/muffler is plugged with mice or rust.

I am replaceing mine with 1 1/2 inch soon.

rusty

[Gary 30U]

Sorry I'm not the only one with this problem.

Pretty sure it's not the exhaust as it is all new.

Could have something to do with timing though. When I drive at regular speed, (35-40) it does seem to load up a bit. thought it was carburation, but could be timeing.

Thanks and Happy Motoring.

Gary

[chetbrz]

The way I look at a problem with overheating is either the radiator can not sufficiently cool the water as it passes through or the engine is developing more heat then the cooling system can shed.   My first suspect would be the radiator.  Is it correct for the car, is it functioning properly.   To trouble shoot the engine side you can use a temperature probe on various places on the block.  Is there a hot spot which is probably not getting water flow?  Sometimes when engines are cleaned out a lot of crud is loosened but not completely flushed out.   Once you have a very hot spot boiling the water it is impossible to balance the cooling system.  I agree with Rusty, my first suspect would be the radiator.

Good luck,  Chet...

[Gary 30U]

Maybe you guys are right, but as I said in the second paragraph of the original post. Wehn this happens it is NOT HOT. You can take the cap off and put your finger down into the water (which is rushing by with lots of circulation) and the water tem is not hot, yes, hot, but not burning.

Is it possible that the water pump is pullling in air around the seal?

As I stated the pump has been rebuilt, but is making noise again and leaks after it is parked.

When I had coolant in it it foamed like crazy when it belched.

Just thinking,

Gary

[chetbrz]

Gary,

My next guess would be an area in your block that has poor water flow.  Water seeps in and fills the pocket.  As you drive you heat the pocket until it turns into steam.  The steam will finally belch out of the engine.  Also the steam will be cooled by the water in the area with good flow so it may appear as a bubble rather then hot white steam.   My guess would be a flow problem in your head or block.  You have a 1930 Dodge.  Did your engine come with a water distribution tube like the 6 cylinder L head. ?   I would try flushing out the head and block with water flow in the opposite direction for normal engine operation.  I would also consider removing the head and looking for signs of crud in the flow ports.  

Second thought:

Cavitation created by an unbalanced water pump propeller might have created the leak and possibly responsible for the large air bubble and foam.  I guess replacing the water pump might be a good place to start.  Does it have the correct sized pulley ?

My 2 cents,   Chet...

[Fendermender]

Hey,
I'm thinkin bushing in water pump and cavitation is present.
This will definately cause poor circulation.

Hope you get it fixed soon.
Regards

[Gary 30U]

Thanks, I'm leaning that way myself.

Gary