Cub blows water out radiator overflow

Farmall Cub Forum -- Questions and answers to all of your Cub related issues.

Moderator: Team Cub

Forum rules
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.
farmallzach
Posts: 3
Joined: Wed Mar 26, 2014 11:39 pm
Zip Code: 54634

Cub blows water out radiator overflow

Postby farmallzach » Fri Apr 17, 2015 10:58 pm

My 1948 Farmall Cub has developed this problem after it has run about 5 minutes water starts spraying out of the radiator overflow with pretty good force. I completely overhauled and restored this tractor about 5 years Ago, and that included a new radiator and cylinder head. The tractor had sat for about 2 years without being run and developed this problem after staring the 1st time after being stored. The tractor had antifreeze in it and has been stored in a heated shed so I know it hasn't froze. I thought maybe it was a faulty head gasket so I installed a new head gasket and head bolts tonight and torqued the head 2 specs in the manual but it still does the same thing. What else could it be, any help would be appreciated, thanks.

User avatar
Barnyard
Team Cub
Team Cub
Posts: 21199
Joined: Tue Aug 07, 2007 3:39 pm
Zip Code: 45030
Tractors Owned: At This Time
40 Farmall Cubs (Round Hood)
2 Farmall Cub (Square Hood)
2 IH Cubs (Square Hood)
5 Lo-Boys (Round Hood)
2 Lo-Boys (Square Hood)
2 Farmall 404's
1 Farmall H
1 Ferguson 20
1 Cub Cadet 125
1 Kubota B-7100
Circle of Safety: Y
Location: OH, New Haven (Hamilton County)

Re: Cub blows water out radiator overflow

Postby Barnyard » Fri Apr 17, 2015 11:04 pm

How full are you filling it? If you put too muck coolant/water in it will blow out until it reaches proper level. The water should be just below the bottom of the baffle in the radiator.
It is common sense to take a method and try it. If it fails, admit it frankly and try another. But above all, try something.
- Franklin D. Roosevelt -

Circle of Safety

User avatar
challenger
5+ Years
5+ Years
Posts: 1087
Joined: Sun Apr 18, 2010 6:22 am
Zip Code: 21742
Tractors Owned: 1955 F Cub (2)
1952 F Cub
1948 F Cub
2155 JD
216 JD
Circle of Safety: Y
Location: Hagerstown MD

Re: Cub blows water out radiator overflow

Postby challenger » Sat Apr 18, 2015 5:49 am

Barnyard has identified the likely cause. As I read the steps already taken by you to address the "problem," it reminds me that understanding the operation of the Cub engine is critical. The Cub engine is not like a modern day engine in a lot of respects, one being its cooling system, which operates by the thermosiphon method. Under this system of cooling, water is moved through the engine by convection. As the coolant heats, it moves out of the hot engine up into the top of the radiator where it begins to cool, falls down through the radiator and then back into the engine again. All this occurs by heat alone. There is no water pump to circulate the coolant and many of the cooling systems do even operate under pressure with a tight spring loaded sealing radiator cap. The systems have no coolant recovery reservoir. Why these features are important is that all coolant expands as its temperature rises. When this happens, excess coolant is going to have to go somewhere. Since there is no expansion reservoir to collect it, it will either go out the cap or the overflow tube. This means that you must allow for expansion of the coolant to take place inside the radiator itself. The proper level to maintain on a cold engine is to keep the water just above the radiator tubes. You will need a small hand flashlight to check this level since there is a baffle inside just below the fill tube and you need to look to either side of this baffle for the water level.

User avatar
Tezell
5+ Years
5+ Years
Posts: 2210
Joined: Fri Sep 10, 2010 5:23 pm
Zip Code: 39861
Tractors Owned: 76 Cub Denim Springs
49 Cub Denim Springs
51 Cub
"Jacksonville" 53 Cub
"Jackson" 76 Cub
"Louie" 64 Cub Fast Hitch
"Paw Paw"71 Cub Fast
Hitch
"Alvin" 72 Cub
"Ugly" 75 Cub
76 Cub Val
Mr. Kirkland" 77 Red Cub
77 Cub "Russell
76 Cub w/fast hitch "Edgar"
76 - 185 Cub Lo Boy
John Deere 2003 - 5320
Circle of Safety: Y
Location: Jakin Georgia

Re: Cub blows water out radiator overflow

Postby Tezell » Sat Apr 18, 2015 7:08 am

Most likely what the others have said. But another thing that is fairly easy to do is flush out the system. I have flushed some pretty bad looking stuff out of the engine before.
"I ain't believing this!"

tst
5+ Years
5+ Years
Posts: 2882
Joined: Tue Jan 12, 2010 2:08 pm
Zip Code: 12514
Circle of Safety: Y

Re: Cub blows water out radiator overflow

Postby tst » Sat Apr 18, 2015 8:57 am

Full is about 2" under the fill neck, any more and it will force it out as Bill said

User avatar
bob in CT
Team Cub Mentor
Team Cub Mentor
Posts: 6000
Joined: Thu Jun 07, 2007 9:34 am
Zip Code: 06040
Tractors Owned: 77 Cub (red); 74 Cub; 52 Cub; 50 Cub ( post-demo)
Circle of Safety: Y
Location: CT, Manchester

Re: Cub blows water out radiator overflow

Postby bob in CT » Sat Apr 18, 2015 6:30 pm

Antifreeze corrosion inhibitors are consumed over time, especially in pockets when there is no circulation. You probably need to flush your system especially since the problem appeared with no other changes after a long lay-up.

This manual shows where the pockets are and what needs to be flushed: http://www.farmallcub.com/[ Sorry, direct links to manual section is not allowed. ]/download.php?fname=./files/Service%20Manuals/Blue%20Ribbon%20Service%20Manuals/GSS-1016%20Cooling%20System%208-17-55.pdf

You need to remove the water neck on the side of the block. You can make a wand connected to a hose out of some copper tubing. I just shoved my pressure washer into the opening and a lot of crud came out.

Here is a post with a wand tool. http://www.farmallcub.com/phpBB2/viewtopic.php?t=18457

farmallzach
Posts: 3
Joined: Wed Mar 26, 2014 11:39 pm
Zip Code: 54634

Re: Cub blows water out radiator overflow

Postby farmallzach » Wed Apr 22, 2015 10:29 pm

Worked on my Cub tonight for a while, I removed the elbow from the block and that was clean, but then stuck a garden hose into the bottom inlet of the radiator, a bunch of black water came out of it, I have come to the conclusion that the radiator core must be plugged up tight, water will not flow through the core at all, this is sad because the radiator was installed new when I restored the tractor a few years back and I bet there hasn't been more than 3 or 4 hours of run time on it since. I really don't want to pull the radiator off the front end if I don't have to, any suggestions?

staninlowerAL
5+ Years
5+ Years
Posts: 3470
Joined: Fri Oct 29, 2010 11:34 pm
Zip Code: 36558
Tractors Owned: Cubs: (3)'49's, (1)'52, (1)'57 IH Cub LoBoy w/FH, (1)'72 154 Number Series Loboy, '76 Longstripe w/FH, Mowers: C-22, Bush Hog 412, Pennington 59, Woods RM42CF, Woods 42, assorted FCub plows, planters, discs, etc. OTHERS: '49 AC B & Ind. Sickle mower, '61 AC D12 Ser 2, '52 8N, '56 Ferguson 35 Deluxe, '53 MM BG (offset), (2) '49 Avery V's, '51 JD M (regular), '56 JD 420C, with Blade and fire plow, '85 JD 850 (Yanmar) w/72" belly mower, '76 Yanmar 1500, Sears Surburban's, MTD's, Jeeps & other misc. "treasures"
Circle of Safety: Y
Location: AL (Southwest)

Re: Cub blows water out radiator overflow

Postby staninlowerAL » Wed Apr 22, 2015 11:29 pm

It might be possible to backflush the radiator through the low drain point on the bottom of the radiator housing. There is a 3/8 pipe thread to water hose adapter available at a good hardware store. You will also need to stop the flow back into the block as well.

User avatar
challenger
5+ Years
5+ Years
Posts: 1087
Joined: Sun Apr 18, 2010 6:22 am
Zip Code: 21742
Tractors Owned: 1955 F Cub (2)
1952 F Cub
1948 F Cub
2155 JD
216 JD
Circle of Safety: Y
Location: Hagerstown MD

Re: Cub blows water out radiator overflow

Postby challenger » Thu Apr 23, 2015 6:01 am

Use a flashlight to look into the top of the radiator to see if the top of the radiator tubes appear plugged. I agree that you should be able to rig up a way to do a back flush with a garden hose by attaching a garden hose to the drain hole at the bottom of the bolster. Make sure the upper radiator hose and radiator cap is off so you do not force crud back into the engine. A problem with this approach is that the bolster is a favorite place for a lot of crude to also collect and you do not want to force this crud up into the radiator core. Therefore, after coupling the hose to the lower drain on the bolster, leave the lower outlet coming out of the bolster open to first flush out any bolster crud. Then, as the water is flowing out of the lower bolster outlet, use your hand to close off this outlet so you can throttle the water pressure being applied to the core. Keep in mind that your garden hose water pressure will likely far exceed the outer limits of your radiator core so you want to use your hand to gauge the water pressure being applied to the core..


  • Similar Topics
    Replies
    Views
    Last post

Return to “Farmall Cub”

Who is online

Users browsing this forum: yellercub and 6 guests