M Farmall Radiator Cap

7483 Views 12 Replies 4 Participants Last post by John M, Dec 23, 2012

bigjohn

Discussion Starter · Dec 20, 2012

Last time I drove the M and shut it off it sounded like the coolant was boiling inside the radiator and the cap popped off. I am going to replace the radiator cap first and I ran into the question of unppressurized, 4lb, or 7lb. I am not sure how to tell which system is on my tractor or which one I need to replace it with especially if the wrong cap being on there is what caused it to pop off in the first place. I have new wind in getting her fully restored, the fiance said if I get finish restoring it we can ride away on it from the wedding reception!!

Thanks guy for the help,
BIGJOHN

Save

1 - 13 of 13 Posts

Red Kiwi

· #2 · Dec 21, 2012

It sounds like your radiator might need a clean out, M's don't usually run too hot, unless the radiator fins are blocked or there's a lot of crud in the cooling system itself. It's usually blocked fins that cause them to heat.
Have a look on the old cap, they usually have 7lb or 4lb marked on it. The one that blew off must have been on it for years, so I think it's more likely to be blocked fins causing the trouble.

Save

bigjohn

Discussion Starter · #3 · Dec 21, 2012

Alright I will make sure to clean it out this weekend and look the cap over to see if I can tell what it is. Thanks for the help

Save

John M

· #4 · Dec 21, 2012

There were 2 different caps used on the M, one for a non pressurized system, the other pressurzed. I pretend to know the difference, cause I really dont, since both are pressurized to a point. However, the non pressurized unit will have WATER on the cap, assuming its original and will look more like the gas cap. The pressurized cap will have a long wing on to aid in removal, again assuming its original. Also the way the cap goes on the rad will tell ya. Look at where the cap goes on, if the cap locks to the inside of the neck, its a non pressurized rad, outside pressurized cap. Stieners shows both on their website, but for some reason Im not able to post the link.

Save

· #5 · Dec 21, 2012

John M said:
There were 2 different caps used on the M, one for a non pressurized system, the other pressurzed. I pretend to know the difference, cause I really dont, since both are pressurized to a point. However, the non pressurized unit will have WATER on the cap, assuming its original and will look more like the gas cap. The pressurized cap will have a long wing on to aid in removal, again assuming its original. Also the way the cap goes on the rad will tell ya. Look at where the cap goes on, if the cap locks to the inside of the neck, its a non pressurized rad, outside pressurized cap. Stieners shows both on their website, but for some reason Im not able to post the link.

http://www.steinertractor.com/Internati ... ling-parts

Save

John M

· #6 · Dec 21, 2012

Thank you sir! For some reason I could copy the link, but couldnt past it...

Save

Peacher79

· #7 · Dec 21, 2012

Tried to post some pictures of the various caps for the M.
I got this reply. Sorry, the board attachment quota has been reached.

Save

bigjohn

Discussion Starter · #8 · Dec 22, 2012

Thanks guys!!! I'm gonna order a new cap just for good measure but a good clean out is on the way. I got the new Steiner catalog and hate looking through it too much because the more I look the more I think I need.

Save

· #9 · Dec 22, 2012

bigjohn said:
Thanks guys!!! I'm gonna order a new cap just for good measure but a good clean out is on the way. I got the new Steiner catalog and hate looking through it too much because the more I look the more I think I need.

Thats why I keep mine in the shed. That way I only look at it if I need something. I'm usually too busy if I'm out there so its pretty safe on the HIGH shelf.

Save

John M

· #10 · Dec 22, 2012

Also make sure your fan belt is tight. Well, tight enough so that you could rotate the engine when pulling on the fan, and the fins of the rad arent plugged up.

Save

John M

· #11 · Dec 22, 2012

Peacher79 said:
Tried to post some pictures of the various caps for the M.
I got this reply. Sorry, the board attachment quota has been reached.

Me too!

Save

bigjohn

Discussion Starter · #12 · Dec 23, 2012

John M said:
Also make sure your fan belt is tight. Well, tight enough so that you could rotate the engine when pulling on the fan, and the fins of the rad arent plugged up.

I was looking at it today and i would be willing to bet that it is going to be the fan belt. Didn't have time to work on it just to check it out. Radiator wasn't too bad but definetely weill need a good cleaning. I will be taking it off soon to paint anyways so be a good time to get started. I am still pretty new to forums but would it be ok with you guys if I started a thread with some pictures of the M and some the progress so that y'all can make any suggestions or things I need to change or just to check it out?

Save

John M

· #13 · Dec 23, 2012

bigjohn said:
John M said:

Also make sure your fan belt is tight. Well, tight enough so that you could rotate the engine when pulling on the fan, and the fins of the rad arent plugged up.

Click to expand...

I was looking at it today and i would be willing to bet that it is going to be the fan belt. Didn't have time to work on it just to check it out. Radiator wasn't too bad but definetely weill need a good cleaning. I will be taking it off soon to paint anyways so be a good time to get started. I am still pretty new to forums but would it be ok with you guys if I started a thread with some pictures of the M and some the progress so that y'all can make any suggestions or things I need to change or just to check it out?

Go for it! WE LOVE PICS, and can give better advice with pics!

Save

1 - 13 of 13 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Top Contributors this Month