Radiator Cap...the final chapter.

[Yohan]

I'm only posting this for guys who do future site-searches and come up confused like me. After searching threads and not finding anything conclusive (other than a Car Quest part # and no Car Quests around here, and a part number that was for a radiator over fill, not a radiator cap), I came up with this...

NAPA Part # 703-1418

This is a seven pound cap that fits on my Deuce, replacing the original with the innertube gasget mod that had coolant blowing all over. It has a little tab to hook the chain up too as well. It was made in Mexico, sorry. I also cleaned the overflow tube, which was gunked up. Happy Deucing!

 

[3rdmdqm]

Let us know how this replacement cap works out. I have similar issue with coolant blowing out of the cap, wondering if your replacement solves that problem. Thanks for the info.

 

[Srjeeper]

Here's more info....

Part # MS35840 - NSN 2930-00-720-2677

www.saturnsurplus.com $13.50

 

[Yohan]

Forgot to mention the price was $7.09 before tax for the cap. I ran it up to temp and have no coolant leaks from the cap. Other than the overflow tube being gunked-up, the cap had a piece of inner tube cut out as a gasget, which I'm sure wasn't sufficient to seal under pressure.

I'm only posting this for info on a working, inexpensive replacement, which is not to say there's anything wrong with the originals that can be had.

I had a time getting the overflow tube clean where the bends are and I almost cut it short and attached a length of rubber hose to it. Finally got it clean, though.

 

[Heavysteven]

I used a NAPA raditor cap for a while. Worked fine, but i decided to go ahead and order an original from a dealer in Atlanta CSI. Oh well i am keeping the napa as a spare.

 

[rlwm211]

I used the same NAPA radiator cap with good results.

RL

 

[Parker2]

I used the same NAPA radiator cap with good results.

RL

Same here. It's a good cap.

 

[3rdmdqm]

Mine started blowing coolant out of the radiator cap. When I checked the overflow tube it had been intentionally plugged shut with body putty. When I cleaned this out I found out why. The overflow tube had completely rusted through at the bottom at the fill neck where they connect. I've either got to do some welding or I need a new radiator. I was curious if your new cap had more tension to prevent pressure buildup from blowing the seal on the cap. After the truck got to its happy fill level, it is currently not blowing any more fluid so I'm chalking it up to overfilling it right now as it seems happy.

 

[rlwm211]

Overflow tube rottted off

My truck's radiator had a few problems when I got it. I obtained the proper solder and flux cleaner at the local welding supply shop and soldered the brackets to the tanks and frame of the radiator where they had been broken off and repaired the joint where the neck is soldered into the upper radiator tank.

Your overflow tube is copper or steel tubing that is soldered onto the neck. I have done some of this type of work before and it requires a large industrial type (read heavy and heavy duity) soldering iron. As I was familiar with how to do this, I went forward with some degree of confidence. It is not hard, but you can screw stuff up if you do not know how to do it, or have the wrong tools.

If you are not comfortable with this type of work, and/or you have never done it before you can drain the system, and pull the radiator and take it to a replair shop if you want this fixed.

The overflow tube vents to the atmosphere and unless you have rigged an overflow tank up, your lack of a working tube simply changes where your radiator overflows to, but does not change anything else. You could do something to stop the coolant from spraying on the belts if it overflows and ignore the tube not being there. It is up to you what you do. As far as radiator performance goes, the lack of an overflow tube being attached to the neck of your radiator has little or no effect on the operation of the radiator.

Just my two cents worth...
RL

 

[DeepAbyss]

Radiator Cap For M35A2

Thanks for the info on the cap. I went yesterday and got one for Napa (Part Number 703-141 for $7.69, with tax in Ga total cost of 8.15. This one didnt have the place for the chain but seems to be working fine. Again thanks for the info.

 

[rockyroad217]

If you're like me and don't have a NAPA worth anything close to you..Here's some part numbers that are interchangeable according to STANT's website...

Carquest 33018
Ford C7TZ8100B
Gates 31308
GM 850802

 

[hilber]

If you're like me and don't have a NAPA worth anything close to you..Here's some part numbers that are interchangeable according to STANT's website...

Carquest 33018
Ford C7TZ8100B
Gates 31308
GM 850802

Thanks