Lower Radiator Hose Clamp Leak - Driving Me Crazy

[Four Lazy C Boss]

I have been plagued with a cooling system leak on my Model A for the last several years, thought I got it fixed several times, and now it is back. The leak is definitely coming from the connection of the lower radiator hose on the bottom outlet pipe of the radiator. I pulled the radiator out last summer (big job) and sent it to a big radiator shop in Billings, even though I couldn’t see anything wrong with the outlet. I got it all back in and the leak has persisted intermittently. Now, I just noticed yesterday, if I tighten up the clamp on the hose, the leak gets much worse. If I loosen the clamp, it goes down to a slow drip. I am mystified. Any ideas?

[Tom Wesenberg]

First make sure you have the correct steel pipe. The 28-9 is different than the 30-1 pipe. Then make sure the pipe doesn't have a pin hole from rust. Mine did and it opened up while I was driving up a long steep hill. I put a bit of Vaseline on the inside of the hose clamp so it can slide as it's tightened up, instead of wanting to bunch up the hose.

[Ray64]

My pipe became crimped from over tightening Was on the bottom and took me 6 months to find. Look there. Just my take on it.

[Four Lazy C Boss]

Hi Tom - Thanks for the quick reply. It is not leaking from the connection with the steel pipe. It is leaking from the clamp on the outlet of the radiator.

[Four Lazy C Boss]

Originally Posted by Ray64

My pipe became crimped from over tightening Was on the bottom and took me 6 months to find. Look there. Just my take on it.

That sounds like it could be the problem. Can I fix it without pulling the radiator again?

[Synchro909]

Sponsored Links (Register now to hide all advertisements)

I had the inlet pipe collapse on me a while ago just the way it sounds like your outlet has. I fixed it by taking the radiator out (sorry, but I think it will have to come out) and bending the pipe back into shape. I thoroughly cleaned it on the inside and soldered a piece of brass sheet over the split ON THE INSIDE. That way, the hose could still seal on the outside and the repair is invisible.

[Four Lazy C Boss]

Originally Posted by Synchro909

I had the inlet pipe collapse on me a while ago just the way it sounds like your outlet has. I fixed it by taking the radiator out (sorry, but I think it will have to come out) and bending the pipe back into shape. I thoroughly cleaned it on the inside and soldered a piece of brass sheet over the split ON THE INSIDE. That way, the hose could still seal on the outside and the repair is invisible.

I think you have likely nailed the problem. I was hoping someone would tell me a way to fix it without pulling the radiator again, but you are probably right that it has to come out. RATS!

[Bill in NJ]

Not sure if this would work but they make an exhaust pipe expander tool to enlarge the pipe. I have one but have not seen it in maybe twenty years. Try getting a loaner one from a auto parts store. Hope this helps you.

[RonC]

Originally Posted by Bill in NJ

Not sure if this would work but they make an exhaust pipe expander tool to enlarge the pipe. I have one but have not seen it in maybe twenty years. Try getting a loaner one from a auto parts store. Hope this helps you.

Harbor freight sells them

[RonC]

Originally Posted by Four Lazy C Boss

I have been plagued with a cooling system leak on my Model A for the last several years, thought I got it fixed several times, and now it is back. The leak is definitely coming from the connection of the lower radiator hose on the bottom outlet pipe of the radiator. I pulled the radiator out last summer (big job) and sent it to a big radiator shop in Billings, even though I couldn’t see anything wrong with the outlet. I got it all back in and the leak has persisted intermittently. Now, I just noticed yesterday, if I tighten up the clamp on the hose, the leak gets much worse. If I loosen the clamp, it goes down to a slow drip. I am mystified. Any ideas?

Coat the inside of the hose with permatex gasket cement.

[Four Lazy C Boss]

Originally Posted by Bill in NJ

Not sure if this would work but they make an exhaust pipe expander tool to enlarge the pipe. I have one but have not seen it in maybe twenty years. Try getting a loaner one from a auto parts store. Hope this helps you.

Good idea. If I could get it in there without pulling the radiator, it would be great. But it is pretty close quarters down in there.

[Four Lazy C Boss]

Originally Posted by RonC

Coat the inside of the hose with permatex gasket cement.

I did that after the last time I pulled the radiator. I think there has to be a little wrinkle or fold in the outlet pipe that will have to be fixed first. Thanks.

[Four Lazy C Boss]

Originally Posted by Synchro909

I had the inlet pipe collapse on me a while ago just the way it sounds like your outlet has. I fixed it by taking the radiator out (sorry, but I think it will have to come out) and bending the pipe back into shape. I thoroughly cleaned it on the inside and soldered a piece of brass sheet over the split ON THE INSIDE. That way, the hose could still seal on the outside and the repair is invisible.

Check out the pic. This explains everything. I was able to pull this fold back out with pliers and got it close to round. It seems to be soft brass. Amazingly, I can’t see or feel any cracks. I am going to buy a tail pipe expander tool to carefully straighten it out the rest of the way and then line the inside of the pipe with JB Weld epoxy. It looks like I can do all this without pulling the radiator. Stand by!

[Four Lazy C Boss]

Originally Posted by Bill in NJ

Not sure if this would work but they make an exhaust pipe expander tool to enlarge the pipe. I have one but have not seen it in maybe twenty years. Try getting a loaner one from a auto parts store. Hope this helps you.

Check out the pic. This explains everything. I was able to pull this fold back out with pliers and got it close to round. It seems to be soft brass. Amazingly, I can’t see or feel any cracks. I am going to buy a tail pipe expander tool to carefully straighten it out the rest of the way and then line the inside of the pipe with JB Weld epoxy. It looks like I can do all this without pulling the radiator. Stand by!

[ModAfan]

The shop that rebuilt my '28 engine a few months ago suggested that I add Bar's Leaks Pelletized Radiator Heavy Duty Stop Leak (PLT11) to the radiator water the first time I filled it. I did. No problems.
It is pelletized and I would suggest you dissolve the pellets in hot water and add the mixture a bit at a time while you fill the radiator with water.

From Bar's website:
Our Bar’s Leaks Pelletized Radiator Heavy Duty Stop Leak is specially formulated to seal larger leaks better than other stop leak products. You’ll find plenty of powder formula radiator stop leak products on the market, but you won’t find a seal coolant leak solution that beats ours in effectiveness. Our Pelletized Radiator Heavy Duty Stop Leak is versatile, too, working safely and effectively on plastic, aluminum and metal radiators, heater cores, gaskets and freeze plugs. It also has a water pump lube that lubricates water pump seals and inhibits the formation of rust and scale.

[Four Lazy C Boss]

Thanks for the tip. I found the problem. Check out my replies above with pic.

[Four Lazy C Boss]

Originally Posted by ModAfan

The shop that rebuilt my '28 engine a few months ago suggested that I add Bar's Leaks Pelletized Radiator Heavy Duty Stop Leak (PLT11) to the radiator water the first time I filled it. I did. No problems.
It is pelletized and I would suggest you dissolve the pellets in hot water and add the mixture a bit at a time while you fill the radiator with water.

From Bar's website:
Our Bar’s Leaks Pelletized Radiator Heavy Duty Stop Leak is specially formulated to seal larger leaks better than other stop leak products. You’ll find plenty of powder formula radiator stop leak products on the market, but you won’t find a seal coolant leak solution that beats ours in effectiveness. Our Pelletized Radiator Heavy Duty Stop Leak is versatile, too, working safely and effectively on plastic, aluminum and metal radiators, heater cores, gaskets and freeze plugs. It also has a water pump lube that lubricates water pump seals and inhibits the formation of rust and scale.

Thanks for the tip. I found the problem. Check out my reply and pic above.

[dean from bozeman]

Yes, wow, that outlet pipe is damaged and no doubt a source of the current leak.

From your original post: 'I have been plagued with a cooling system leak on my Model A for the last several years, thought I got it fixed several times, and now it is back. The leak is definitely coming from the connection of the lower radiator hose on the bottom outlet pipe of the radiator. '

The crimped outlet could not have been the cause of the original leak...otherwise you or the radiator man would have caught it. Hopefully the original leak was repaired at the radiator shop and this new leak can be fixed with a tail pipe expander tool. Just don't eat your Wheaties before putting the lower hose back on...a little vaseline would help too.

[Marshall V. Daut]

When you put the lower radiator hose back on the repaired and re-shaped outlet pipe, coat the pipe with a generous amount of Indian Head Shellac or something comparable. When this goop gets hot, it will expand and really seal the hose to the pipe. I also run a ceramic sealer through the system the first time. That will seal small dribble leaks (such as along the side of the block between the head), radiator hose connections and help seal the new head gasket. Use only water while doing this, no anti-freeze. Run the engine for the specified time per instructions on the bottle and then drain. Allow the air to cure the ceramic sealer overnight by leaving off the radiator cap. You should not be plagued by any more leaks if you follow this procedure. Just be careful when tightening the lower hose clamp. Place it as a close to the re-enforcing rib along the pipe's throat as possible where it is strongest. Placing the clamp closer to the radiator is just asking for a collapsed outlet, as you have experienced.
Marshall

[Four Lazy C Boss]

Originally Posted by dean from bozeman

Yes, wow, that outlet pipe is damaged and no doubt a source of the current leak.

From your original post: 'I have been plagued with a cooling system leak on my Model A for the last several years, thought I got it fixed several times, and now it is back. The leak is definitely coming from the connection of the lower radiator hose on the bottom outlet pipe of the radiator. '

The crimped outlet could not have been the cause of the original leak...otherwise you or the radiator man would have caught it. Hopefully the original leak was repaired at the radiator shop and this new leak can be fixed with a tail pipe expander tool. Just don't eat your Wheaties before putting the lower hose back on...a little vaseline would help too.

You are exactly right.