Help with radiator cap spray
- Thread starter Lee Mitch
- Start date
Purdy Swoft
Well-known member
I agree with Bill !!! I found an original cap for my roadster . I think that the original style caps look better . In my opinion the only thing that the locking caps are good for is to ruin the radiator neck and to leak . I had l;ots of problems with the thermo quail that I used on the coupe , my daughter liked it so I finally gave it to her . On the other hand if the radiator neck is damaged you may still have leaks . Even an original cap needs a good tight seal .
Every model A that I've ever owned would spray water out around the cap on a hard uphill pull under full throttle, Its a common trait of the model A . It can even happen on level ground under hard accelleration . Cutting down the impeller and getting a good seal at the radiator cap always solved the problem for me . An old partially plugged radiator or a new radiator with smaller or less tubes just can't handle the pressure that the water pump puts out . I guess that a cut down impeller could be called a band aid but if it solves the problem , so be it !!! If it wasn't common why would Snyders offer a cut down impeller . If the radiator can't handle the flow , the water has got to go somewhere . I can understand how a person would be reluctant to modify an expensive new leak proof pump . I'm not trying to tell anybody what they have to do . This has just been my experience .
Glenn Thoreson
Senior Member
I've found those MotoMeters are not at all accurate. It is true that over filling will cause coolant to come out. I always fill to cover the tubes and let the thing seek it's own level.
Are you running a thermostat? If so, it could be faulty. If not, a thermostat will close down the size of the hose and help control the flow of coolant. !60 degree 'stat for your location.
There is the possibility that rust chunks have washed into the radiator and blocked some of the tubes. Always a problem with all flathead Fords. Try back flushing the radiator. Never run plain water in these things.
Are you running a thermostat? If so, it could be faulty. If not, a thermostat will close down the size of the hose and help control the flow of coolant. !60 degree 'stat for your location.
There is the possibility that rust chunks have washed into the radiator and blocked some of the tubes. Always a problem with all flathead Fords. Try back flushing the radiator. Never run plain water in these things.
1931 flamingo
Well-known member
As others have suggested, ck the gaskets..................Been There Done That.
Paul in CT
Paul in CT
California Travieso
Well-known member
Purdy,
Those are both great ideas. My problem is getting the cap off. I think the Allen screw is stripped and it's so small it's going to be a pain taking it out.
I was thinking about cutting down the impeller but was worried that it would be unbalanced. I guess the vanes are too small to cause a problem even if they are unbalanced a little bit.
David Serrano
Purdy Swoft
Well-known member
David , The nuts under the allen head screws could be turning , preventing the screws from backing out . You may have to drill out the screws if all else fails . I have had good luck grinding the tips of the impeller without getting things noticably out of balance . You could use the cut doen impeller that Snyders sells . The cut down impeller is on page A-140 of the Snyders catalog , part # A-8501-iM Price $8.50
California Travieso
Well-known member
Purdy,
Those are both great ideas. My problem is getting the locking cap off. I think the Allen screw is stripped and it's so small it's going to be a pain taking it out.
I was thinking about cutting down the impeller but was worried that it would be unbalanced. I guess the vanes are too small to cause a problem even if they are unbalanced a little bit.
David Serrano
California Travieso
Well-known member
Oops I double posted.
Purdy,
Thanks for the advice. I might just buy the one from Snyder's.
David Serrano
Purdy,
Thanks for the advice. I might just buy the one from Snyder's.
David Serrano
Chuck Sea/Tac
Well-known member
I haven’t tried to prove it, but I think it can. It’s siphening the water in the block.
BILL WILLIAMSON
Well-known member
Yo' David,
"Maybe" it's time to gently warm the neck, pop it OFF, remove the shell & solder on a NEW Filler Neck, available through the suppliers.---It can be easily done, IN THE CAR, with an inexpensive Propane Torch.
Bill W.
Purdy Swoft
Well-known member
Its real easy to get the neck just a little off center . If the neck is a little off center it can cause the cap to rub the radiator shell and be difficult to get off and on . In worse cases, if it is more than a little off center the radiator shell won't fit over the neck, its happened to me. It can be a real PAIN to correct !!!
Purdy Swoft
Well-known member
Not for the sake of disagreement , I figure the pump can pull as much coolant as it can push. As the pump pushes coolant out arround the cap and out the over flow tube the coolant level drops . Just my thought . I won't try to prove anything .
BILL WILLIAMSON
Well-known member
Nobody's just trying to be "RIGHT", just trying to HELP!
Bill W.
Bill W.
Purdy Swoft
Well-known member
Right on bro , I'm not the best at soldering radiators !!! an experienced radiator man would have no problem .
BILL WILLIAMSON
Well-known member
Chief worked part time at Orville Mannings' Radumator Shop & lurned me some of the BASICS.
I could "possibly" Solder on a body panel! These skills also helped me be a "pretty" good Body Leader. I can still smell the BEES'WAX!When burning cars for scrapping, at the Wrecking Yard, I'd collect BIG "cow patties" of lead, under the car. Then melt it & form sticks of it, in an angle iron "mold" & some went to a Friend, that made Fishin' Weights, along with savin' wheel balancing weights for him. Chief taught me the value of "exotic" metals.
Bill Stucktight
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Imagine an engine running a little hot, say 185. Maybe there's a hot spot in a little shielded corner running 200 degrees. You punch the gas and the pump spins up. The flow makes the pressure highest at the exit of the pump and lowest at the entrance to the pump and in-between pressure in between. All you need is for the pressure to drop in the block by enough to boil 200 degree water and you'll pull a steam bubble in the block. Then the top tank will fill by the same size as the steam bubble. Too much , and it overflows. So yes, the pump can push more out than it draws from the radiator. It draws from the block.
California Travieso
Well-known member
Bill,
I'm tempted to try but I'm really a rookie. If my father-in-law was still alive I'm sure he could have done it. He grew up on a farm in Hanford in the 1930's and he would tackle anything mechanical just to see if he could do it.
In WW II, the Army put him in the Civil Engineering Corps building bridges in France after D-day. He was stationed in England first, and he said the pub keepers would get mad at the GIs because they would come in and drink all the beer. Beer was rationed and the pubs were only allowed a couple kegs and they had nothing left to sell to the locals. The locals generally nursed a pint all night.
The Early Ford Store recommended a Radiator shop in the San Gabriel Valley that still works on old radiators. Most radiator shops today just want to replace the plastic or aluminum radiators with new ones. Even I can do that.
Thanks guys,
David Serrano
Jacksonlll
Well-known member
Simon, good analysis. The steam bubble is the key. Without a bubble, the pump output is controlled by the radiator outlet.
SeaSlugs
Well-known member
Good point, makes cleaning out rust/gunk behind cyl #4 even more important. But in this particular posters case he says he has a recored radiator and rebuilt engine - i would hope whoever rebuilt the engine dunked and cleaned inside the waterjacket.
This is where one of those thermal cameras would be great to use to detect hot spots in both block and radiator.