Removing the Radiator Cap on a 1931 Model A

Cornishman

Cornishman

Senior Member
I am in the process of replacing the waterpump on my car. As the car has a four blade fan I need to remove the radiator. Following the instructions in my Les Andrews Volume 1 I started removing the radiator shell. All was going smoothly until I reached stage 7, remove the radiator cap. How? I presume that I need to undo the two Allen (hexagonal) screws inside the filler. Is this correct? There are no detailed instructions. Can anybody help?
 
Yes and turn inward carefully do not unscrew all the way as the brass ends will fall in rad. Easy will come off easy. They go under the lip of spout.
 

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You can't just turn the cap counterclockwise and remove it? I guess I don't understand what the difficulty is.
 
I have discovered that it is a locking cap held in place by two Allen headed screws. I now have a few days' delay before discovering how easy it is to remove as I have had to order a set of imperial Allen keys, all mine are metric.
 
If it is other than a "regular" cap, you may have a Quail(?) meter type or something like this. I know on my 1929 I did have to use an Allen wrench to remove it. Don't know if you have the same on your 1931. And yes they are not metric.

I know I had a few choice words about my cap the first time I took it off until I discovered the Allen screw.

Forget the above, did not post till a couple of above posts. So that is not your problem.
 
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Fred K-OR said:
If it is other than a "regular" cap, you may have a Moto (?) meter type or something like this. I know on my 1929 I did have to use an Allen wrench to remove it. Don't know if you have the same on your 1931. And yes they are not metric.

I know I had a few choice words about my cap the first time I took it off until I discovered the Allen screw.
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Quite right. I was just a bit surprised that the Mechanics' Handbook dismissed it so simply as everything else is described in such detail.
 
Cornishman said:
I have discovered that it is a locking cap held in place by two Allen headed screws. I now have a few days' delay before discovering how easy it is to remove as I have had to order a set of imperial Allen keys, all mine are metric.
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There should be a metric key that is close enough to get it to turn the screws. I can't ever keep my US Standard keys and metrics straight, they are all mixed up most of the time.
 
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I tried every key I have without any luck so I've ordered the imperial set anyway. I've got other jobs to do on the car while I'm waiting for them to arrive.
 
I've pulled the radiator before leaving the shell on. It's more difficult to remove and install the radiator mounting bolts but you can still do it.

Sent from my Nexus 6P using Tapatalk
 
On my 28 and 29 I remove the radiator and shell as a unit.

Won't the fan with 4 blades come out by just tipping the radiator ahead?
Maybe remove the light bar to tip it more.
 
Cornishman said:
Quite right. I was just a bit surprised that the Mechanics' Handbook dismissed it so simply as everything else is described in such detail.
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There are a couple of different caps so not having detailed instructions on a specific cap is not a surprise.

Tom Wesenberg said:
On my 28 and 29 I remove the radiator and shell as a unit.

Won't the fan with 4 blades come out by just tipping the radiator ahead?
Maybe remove the light bar to tip it more.
Click to expand...

That is how I have done it. I also place a piece of cardboard between the fan and radiator.
 
Cornishman, forgive me if I am pointing out the obvious, but I didn't see anyone else mention this...

The reason that Les Andrews doesn't explain how to remove this is because it is not standard. What you have is an aftermarket "anti-theft" radiator cap. It is designed to keep someone from stealing your Moto-Meter, or other fancy radiator cap. The original radiator cap was just a quarter turn and lift it off. This one requires tools to remove, and will (hopefully) discourage a thief.

I don't remember what size Allen (Hex) wrench you need, but I don't think it is metric.

Ken
 
KGBnut said:
Cornishman, forgive me if I am pointing out the obvious, but I didn't see anyone else mention this...

The reason that Les Andrews doesn't explain how to remove this is because it is not standard. What you have is an aftermarket "anti-theft" radiator cap. It is designed to keep someone from stealing your Moto-Meter, or other fancy radiator cap. The original radiator cap was just a quarter turn and lift it off. This one requires tools to remove, and will (hopefully) discourage a thief.

I don't remember what size Allen (Hex) wrench you need, but I don't think it is metric.

Ken
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That would have been my thought but there is a big but. On the very same page he explains about how to remove aftermarket headlamp systems. As its obvious that a large number of cars have been fitted with the Allen screws I think it's strange that that is not mentioned as well. It really is no problem, I'm quite happy to wait for the Allen keys to arrive so I can do the job properly. In England we have a saying, 'If a job's worth doing it's worth doing well.'
 
Gary WA said:
Yes and turn inward carefully do not unscrew all the way as the brass ends will fall in rad. Easy will come off easy. They go under the lip of spout.
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I should have said, 'Thank you' for this reply days ago. Sorry. It is exactly what I needed to know.:)
 
If you don't have time to do it right the first time, where are you going to find time to do it right?
 
I took a look at mine, and much to my surprise, the Allen heads are metric. Mine are 4.5 mm. I never would have guessed.

Ken
 

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KGBnut said:
I took a look at mine, and much to my surprise, the Allen heads are metric. Mine are 4.5 mm. I never would have guessed.

Ken
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That makes sense, 5mm was too big and 4mm too small and I don't have a 4.5mm. The set I've ordered does. Thanks.
 
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