Radiator boiling after use

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Radiator boiling after use

Postby extremewhitetail » Sat Sep 23, 2017 1:28 am

Hey Everyone - I have been all over the site looking for a remedy for my problem without any luck. I have a 1965 Farmall Cub that has recently be gone through completely. When the motor was tore down it was power washed to remove any scale build up, that goes for the front bolster as well. I put a new radiator and gasket on it and no leaks can be found anywhere. I have a nonpressurize cap.

My problem is when I fill the radiator with 50/50 mix to the level stated in the manual during use a majority of it leaks out. Dang near a gallon. After about an hour's use the water/antifreeze is boiling.
Absolutely no leaks anywhere. I'm afraid I'm going ruin the engine with it getting this hot. What do I need to do.

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Re: Radiator boiling after use

Postby inairam » Sat Sep 23, 2017 7:13 am

I once had a gasket slip and partially block the lower coolant tube. Is the belt on the fan tight?

If the block and bolster are clean and the radiator is new and the fan belt is tight then some type of blockage is where I would go.
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Re: Radiator boiling after use

Postby Jim Becker » Sat Sep 23, 2017 10:31 am

One possibility is a blown head gasket. Were the head and top of the block both checked for flatness as part of the engine work? Were the head bolts retorqued after the engine was warmed up? I suggest doing a compression test as a good first step towards figuring out what is going on.

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Re: Radiator boiling after use

Postby ntrenn » Sat Sep 23, 2017 12:51 pm

Compression test will find gross leaks. Also try a coolant side leakdown test. Car stores will rent the coolant pressure testers. A more expensive option is to test the coolant for combustion products.
Fan blade backwards?
How is the airflow? Should move LOTS of air.
Do you have a laser thermometer? Check temperatures....at each cylinder, at bottom hose, at coolant outlet.

And...it never ran hot before....thats always my luck...

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Re: Radiator boiling after use

Postby Eugene » Sat Sep 23, 2017 1:35 pm

Are you over filling the radiator? Radiator only needs to be filled slightly above the tubes and not to the radiator cap.

If you are losing about a gallon of coolant, there should be evidence some place. Have you checked the radiator's over flow tube for leakage?

Check the ignition timing. Yup. Check the ignition timing, that's fast and easy. Off a bit will cause over heating.

The Cub engine runs hot, around 200 degrees. Hot weather will increase the coolant temperature.

Did you pressure spray the engine coolant passages? I assume so from the initial post.

Clean chaff and debris from the radiator?
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Re: Radiator boiling after use

Postby Dave2017 » Sat Sep 23, 2017 1:42 pm

Might double check the carb adjustment. A lean mixture can cause over heating issues too.
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Re: Radiator boiling after use

Postby outdoors4evr » Mon Sep 25, 2017 7:58 am

I've had my 184 boiling hot before. When that occurs I usually find a lot of grass and weed chaff buildup in front of the radiator or a low coolant level in the radiator. (it's a fine balance between overfilled and under filled)
If I am done mowing, park the tractor and don't see any drops under the tractor the next day, then I usually add a cup of antifreeze (mixed 50/50) to the radiator.
I probably average adding a cup per month of mowing use.
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