Boils over

[jwaldrich]

Pulled the radiator and took it to a radiator shop. They are doing a flow check and whatever other tests they do. Their visual inspection comments indicated they thought the core looked good from the outside.

What is a good indicator the water pump is bad? The newer water pumps had a "seep hole" that pisses water out when the pump is bad.

[Brentwood Bob]

You think you have a waterpump with sealed bearings, so when you spin the shaft the bearings should be quiet, no looseness, and no movement of shaft fore, and aft.
Seals should be good, and running on a smooth clean shaft surface.
Depending on what fan blade you are running look for galling, fatique cracks, warping, and balance.
Bob

[1931 flamingo]

Hopefully they don't pressure check with more than 2 or 3 pounds. The A is NOT a pressurized system.
Paul in CT

[jwaldrich]

Originally Posted by 1931 flamingo

If the water isn't going down the o/flow tube where is it going??
Is it coming out around the rad cap?? Repl gasket.
Have you ck'd timing??
Where is your spark lever??
Do you have a temp gauge to verify it's boiling or just finding it's level??
How much water/liquid do you add after it "boils" over""
Paul in CT

Could be over-filled.
Coming out around the rad cap.
Spark lever is at 50% which is where she runs best.
Just MotoMeter at this time.

Radiator shop is testing the rad now. I'll go see if the water pump is free wheeling.

[Jacksonlll]

Most 80 year old radiators are plugged, period. If you can't drive 45 mph for 10 min straight without boiling over, you are plugged.
I just ran a test on an unplugged radiator. I ran the engine at 2100 rpm,(45mph), and measured the pressure in the lower hose. I was looking for the low pressure at that point, caused by the pump trying to suck the water out of the core. I got a big fat ZERO. No vacuum at all. A plugged core would restrict flow and cause a vacuum there. I got none.
You can conclude from this, that, if the core is not plugged, there is no way the pump can pump too much water. A good core can take all the water the pump can give it.
The answer is to rod out the core, but how. Shops will not do it. I'm trying to figure out a way myself. I have two old radiators to play with.

[eagle]

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Originally Posted by Jacksonlll

Most 80 year old radiators are plugged, period. If you can't drive 45 mph for 10 min straight without boiling over, you are plugged.
I just ran a test on an unplugged radiator. I ran the engine at 2100 rpm,(45mph), and measured the pressure in the lower hose. I was looking for the low pressure at that point, caused by the pump trying to suck the water out of the core. I got a big fat ZERO. No vacuum at all. A plugged core would restrict flow and cause a vacuum there. I got none.
You can conclude from this, that, if the core is not plugged, there is no way the pump can pump too much water. A good core can take all the water the pump can give it.
The answer is to rod out the core, but how. Shops will not do it. I'm trying to figure out a way myself. I have two old radiators to play with.

FINALLY some actual scientific testing done! What type of vacuum gauge did you use and how did you incorporate it into the lower hose? Would be very interesting to run the test on an A with a known partially plugged radiator.

[sethkestenbaum]

John,

I had similar issues with my original 29 radiator. It was a function of clogged tubes. If you try the vinegar treatment to break up some of the clogs, you might want to add a gano filter to catch any excess particles that could then go loose and clog other tubes. I wound up changing my radiator for a new one and will eventually have the original one rodded out.

Seth

[Jacksonlll]

Eagle, I just used some clear tubing, held it above the top tank to see how far the level in the tube dropped. It did not move. Earlier, I tried a vacuum gage and thought it was broken when I got zero.
I put a 1/8 in. nipple in the petcock hole and attached the tube to that.
I want to do this same thing on a plugged core to see how severe it is. jack

[jwaldrich]

Originally Posted by Brentwood Bob

You think you have a waterpump with sealed bearings, so when you spin the shaft the bearings should be quiet, no looseness, and no movement of shaft fore, and aft.
Seals should be good, and running on a smooth clean shaft surface.
Depending on what fan blade you are running look for galling, fatique cracks, warping, and balance.
Bob

2 bladed fan. I took the fan belt loose and there is no fore and aft movement but it does not move freely. By that I mean you cannot "spin" it at all and my thought is that it is harder to turn than it should be. Keep in mind I have no experience with A's.
I do not have to "man-handle" the fan to turn it but the belt better be grabbin' pretty good.

It always turned "OK" when idling in the barn.

[jwaldrich]

Just spoke with the radiator shop. My rad is almost totally plugged. They will try to rod it out, otherwise, re-core time.

[Jim/GA]

Originally Posted by jwaldrich

Just spoke with the radiator shop. My rad is almost totally plugged. They will try to rod it out, otherwise, re-core time.

Don't be discouraged. This is so common. Put a heavy duty core in if you have to re-core and you will never have to worry about it again.

[Jacksonlll]

John, let us know if they will take it apart and rod it out. The problem is, when they try to remove the top tank, the whole thing comes apart. Most shops know better than to mess with taking off the top tank. Keep us posted. Jack

[Tom Wesenberg]

Originally Posted by Jacksonlll

Eagle, I just used some clear tubing, held it above the top tank to see how far the level in the tube dropped. It did not move. Earlier, I tried a vacuum gage and thought it was broken when I got zero.
I put a 1/8 in. nipple in the petcock hole and attached the tube to that.
I want to do this same thing on a plugged core to see how severe it is. jack

Good idea for a test.
I agree that when I work on my radiator I will remove my bottom tank and use my long thin drill bit to try to clean out the tubes. I'll machine a small knob and use a setscrew to tighten it to the bit, then twist it with my fingers to carefully remove the junk. I've removed the tanks on a couple Studebaker radiators, but haven't removed tanks on any of my Model A radiators yet.