Ford 8N dribbling coolant out of radiator overflow, not overfilled.

[gstrom99]

3) I have attached detailed, close up photos of the radiator fill neck. I believe it to be the correct radiator for the tractor. The fill neck is noticeably bent, which myself and my brother now believe is the cause of my issue. How would I go about straightening it? Would this kind of repair require a radiator shop?

Good pics. 2 quarts down is too much to ignore. The cap may have a hard time sealing on that distorted neck. A radiator shop (these are getting hard to find now) can advise/repair on that neck. What kind of sender is it, that goes in the hose? May be an extra restriction there. Try taking your t/stat and temp sender back out, going back to square one...

 

[careyo63]

Good advice IMO. Havent read all the way back but seen no mention of it?
Has there been a pressure test of how much pressure is in the radiator running. Should be 4 PSI cap. TSC has a 7 PSI. cap. Been awhile. Is it a 9n Radiator causing a problem.
This is true as I recall.

1939 9N radiator was UNPRESSURIZED until about 1942 at which time Ford changed to 4-psi radiator system. Ford also issued a field advisory, that it was ok to upgrade to the 4-psi radiator for non-pressureized 9N's. All ya haffta do is change the radiator. (and cap)

NOTE: pressurized and un-pressurized radiator caps are INCOMPATIBLE. So you have to change the whole radiator.

 

[BossofBBQ]

I have no idea how much pressure the radiator has, I’m also not sure if it’s an earlier 9N radiator or the proper 8N one. I attached photos of the temp sender I have. Because of its design, it does cause some restriction, but I wouldn’t think it’s a lot. Also, I have included a photo of my new radiator cap next to my old cap. The new one is shiny chrome, old one is standard black.

I will remove the tstat and temp sender sometime tomorrow to see if it makes a difference, as I am not currently by the tractor today.

 

[flyerdan]

Without a recovery system you'll always have air in the radiator due to thermodynamics. I would put a 2 liter bottle with the overflow tube submerged at the bottom, take a scotchbrite disc and clean up the top seal on the neck, and verify that the radiator cap has a rubber seal at the top and bottom, so when it cools down it has to draw fluid back in, rather than atmosphere. The bend in the filler neck shouldn't be an issue, unless there is a crack that would allow air back in.

 

[4Liberty]

I have no idea how much pressure the radiator has, I’m also not sure if it’s an earlier 9N radiator or the proper 8N one. I attached photos of the temp sender I have. Because of its design, it does cause some restriction, but I wouldn’t think it’s a lot. Also, I have included a photo of my new radiator cap next to my old cap. The new one is shiny chrome, old one is standard black.

I will remove the tstat and temp sender sometime tomorrow to see if it makes a difference, as I am not currently by the tractor today.

I don’t think the new cap or that sender are contributing to your problem. I was interested in seeing what the seal on the new cap looked like. Both the seal and brass cover on the cap look correct for the type of system you have.

 

[4Liberty]

Also the thermostat needs to be as close to the head as possible.

 

[BossofBBQ]

My brother, father and I think the filler neck is “bowed” upwards just enough to cause the seal leak.

Radiator is not overfilled, I always top it off to maybe 1-1.5” above the fins. Attached is a photo of a straight edge lined up over the fill neck. There is a sliver of light in the middle, showing the bend. Could this be the cause of my issues?

 

[John0829]

The 8N tractors want the coolant to barely and I do mean barely, to just cover the tubes of the core. Anything more than that and they will puke it out, even the NAA and hundred series tractors are picky about the level.

I went back and reread your description and I now think you indeed have compression getting into the radiator. You said you held your hand on the neck but could feel no pressure, you would not, the pressure if any would have exited out the overflow tube unless you had it somehow blocked.

At this stage I recommend you do a pressure test of the system. You should be able to borrow a tester from one of the auto parts stores near you that have a tool lending program

 

[BossofBBQ]

Right- I will borrow a tester from our local Autozone shortly. I’ll update yall with the results. It might be a few days; I’ve been swamped at work lately and haven’t had much time to tinker on the ole girl.

I never thought my first thread would be 6 pages and have 10k+ views- TBN continues to amaze me. Thank you all for your valuable insight and suggestions, I’m proud to be a part of the N tractor world!