collant leak on old tractor

[opticsguy]

Not sure where to post this:

Have a coolant leak on my 1930 JD model GP tractor.  Very small leak but enough to make me worry . . . .   The GP is a thermosyphon system, no water pump, so how well would some kind of stop leak product work in this system?  I have had great luck with stop leak type products in the past but never used in a thermosyphon system.

thanks!!

[Ernie]

Rusted frost plug?  With my luck it was the one at the back of the block inside the bell housing on a tractor I had borrowed from a good friend.  I always like to return a borrowed tool or machine in at least a good a condition as when I picked it up.  Splitting the old Ford was not cheap but we are still great mates.

[beenthere]

Is it leaking into a cylinder?
Any chance the block is cracked from water freezing in the past?
If not, maybe just a gasket.
They are not too difficult to work on, being just the two cylinders.

Prolly have nothing to lose to give the stop leak a try.

[julio]

I would try some liquid glass. It will fix head gasket and cracked blocks

[Axe Handle Hound]

opticsguy- you didn't say if you know where the leak is...assuming you do, is there a reason you don't want to go ahead and fix it? 

[Corley5]

I've always been told that stop leak stuff didn't work with thermsiphon.  It just settles out.

[beenthere]

I would expect that to be right. Might work if the leak were in the radiator, but not the block or a gasket.

Would be interested in hearing if the location of the leak is known.  Opticsguy... any idea?

[John Woodworth]

If it,s anything other than a headgasket drain the tractor and flush with water if it's had anti-freeze, get a can of K&W Block seal and mix it good with the amount of water the system takes in a 5 gal. bucket, mix it good and put in the tractor and run it up to temperature, the longer the better with your type of system, then drain everything and leave open to air for 24hrs, should do the job.

[opticsguy]

OP here.  Not really sure where the leak is but the engine oil does not look like real oil so i suspect a gasket leak?  Then again the oil is not totally destroyed by water, so i suspect a very small leak over time.  One person asked why not just fix it?  Well, time and money and . . . time.  Looking for a short time quick fix and repair later after the show season.

[Axe Handle Hound]

Speaking as someone who owns a rusty 1945 Allis Chalmers C I think that tractor repair should be part of tractor shows.  It's sure a large part of owning these old things. 

[Corley5]

A leak that small on a machine that's idling around at a show won't hurt it a bit.  I wouldn't worry about it until after the season. 

[snowstorm]

i remember working on a few 60,s back in the 70,s while at the jd dealer. seems like they would leak rain water in thru one of the inspection covers. there was a square drive coupling for the oil pump if there was enought water in there it would freeze and when started it would break the coupling

[Al_Smith]

I'll tell you two things that will work at least temporily .Black pepper or fine ground grain .

I had an old HG Cletrac crawler with a Hercules 4 banger,thermo syphon .Never put antifreeze in ,just drained it .Fire it up ,let it warm up and dump about a table spoon full of black pepper in the radiator,no more leaky until the next go round .--BTW I finally did solder up the radiator just didn't feel like fooling with it in January.

Another old stand by is sodium silicate commonly called "water glass".Now this you have to dump in the system and let it run until the leak stops then drain the water out so it will set up .Used that on a D4 Cat that cracked the block behind the injector pump .Welded it but old Caterpillar cast iron and old Ford limestome cast is the toughest cast iron ever made to get right .Must have worked it's got the same water and antifreeze in it it did when I parked it 12 years ago .

[Al_Smith]

  there was a square drive coupling for the oil pump if there was enought water in there it would freeze and when started it would break the coupling

That's pretty common but most people overlook it .Which has caused many to get new rod bearings bearings .For some reason it doesn't seem to cause any damage to the piston or rings though .