The kiss of Death? YM1700

[Car Doc]

It isn't the kiss of death but it is the kick in the arse we all get sometimes with used stuff. If you have decent access to the cracked area a mig will probably do as good as anything on a nice clean surface.

A simple way to pressure test any radiator or cooling system (like after welding one etc) fyi is carefully put shop air into the overflow tube at the radiator neck with the rad cap on it and it will hold the amount of pressure the cap is calibrated at. You can overdo it if you dont back off but if careful it works fine. Use about 10-20 drops of dawn dish soap in a spray bottle with water and spray down the welded area and it will bubble if it isn't fixed.

Nickle arc welding rod is great too as long as you know how to use it. I have welded plenty of older Toyota exhaust manifolds with plain old mig 75/25 mix and mild steel .030 wire make it look like a stack of dimes keeps the heat down.

Disconnect the negative battery cable before doing any welding you dont want a fried alternator. :thumbsup:

 

[California]

Found some old photos of my nickel-rod repairs to cast iron. If I can get good results with no experience - then a pro job on your tractor should be good as new.

Pic1 Re-attaching the leg tabs where they broke off the legs.

Pic2 Back in service.

 

[puresol]

Ok I made the "repair". Cleaned and sanded the surface, then I cleaned and sanded the surface, when I was done I cleaned and sanded the surface. Good thing I did because it appeared the crack may have been bigger, or capable of getting bigger. I drilled the ends a little, then a few spots in the middle. Anyway I ran the tractor tonight, no load. 15-20min at 1000rpm and 15-20min at 1500rpm. No leak at the crack. I will put it to the test next weekend with some light bush hogging. But---and there is always a but--- the new radiator cap leaks! The old 16psi motor craft cap does not leak. Im not sure the motorcraft cap is actually holding 16psi. Would a lower psi cap be a problem? Wouldnt it make the tractor get to operating temp quicker?

 

[winston1]

Congratulations on the block repair. Maybe it will hold up. I'm wondering if you could be overheating causing your new 13lb cap to leak? Probably don't want to spend the money but these work good. Non-Contact Infrared Laser Thermometer

 

[puresol]

What temp should I be running? Why wouldnt it overheat with the other cap?

 

[California]

I don't think a pressure cap will help it warm up sooner. 13 psi is correct, and should raise the boiling point of your coolant some 20 degrees. (Plus the antifreeze raises the boiling point too, depending on concentration).

I'm not sure of YM1700 but I measured around 200' and below, at all points on my YM240 using a non-contact thermometer like Winston described. I think your Temp warning light comes on around 235-250' (???) and so long as you get readings comfortably below that, no problem.

It is normal for coolant to expand and get pushed over to the overflow bottle after it warms up. Then get sucked back to the radiator as it cools. But if that cap dribbles coolant to the outside, it may have a problem.

I use a 13~14 psi lever-release cap specified for '72 Datsun (from Autozone) and that works fine.

 

[Soundguy]

i'd braze or reweld it..... as long as it's not got water into the oil, and is only an exterior leak.,

to do this.. you'll need to drain the block.. and I'd grind and preheat the area.

depending on how close to the head.. I might go for a new head gasket..

 

[puresol]

i'd braze or reweld it..... as long as it's not got water into the oil, and is only an exterior leak.,

to do this.. you'll need to drain the block.. and I'd grind and preheat the area.

depending on how close to the head.. I might go for a new head gasket..

Im approx 2.5" below the head gasket. I am thinking about brazing if/when JB fails. Will have to do some studying, never done it before, but that never stops me. No water in oil

 

[puresol]

I don't think a pressure cap will help it warm up sooner. 13 psi is correct, and should raise the boiling point of your coolant some 20 degrees. (Plus the antifreeze raises the boiling point too, depending on concentration).

I'm not sure of YM1700 but I measured around 200' and below, at all points on my YM240 using a non-contact thermometer like Winston described. I think your Temp warning light comes on around 235-250' (???) and so long as you get readings comfortably below that, no problem.

It is normal for coolant to expand and get pushed over to the overflow bottle after it warms up. Then get sucked back to the radiator as it cools. But if that cap dribbles coolant to the outside, it may have a problem.

I use a 13~14 psi lever-release cap specified for '72 Datsun (from Autozone) and that works fine.

With the motorcraft cap I get movement of coolant into and out of the expansion tank. Shoot the thermometer winsto post isnt but 20 dollar. I may have to pick one up. The Hoye (no offense intended only my observation) cap seems very cheaply made. I need to order an alternator and voltage regulator for a Datsun next week for my tractor, will look into getting radiator cap also. Ive never flushed the cooling system, Ive never flushed any cooling system on anything, Is it as easy as it seem or am I missing something?

 

[Soundguy]

the thing witht he jb is the heat/cool cycles cause flexing.. plus the coolant has oils in it.. they will seep and run and lift that jv when you least expect it.

IMHO.. welding is just as easy.. or easier even than welding.

another GOOD option for that location is silver solder. CI/steel solders EASILLY. the temps are fine as you won't be hitting 300.. get some paste flux and plumbers solder.. wire brush the area.. drill sop the crack.. vcut it.. flux the bajeebers out of it.. then tin t he heck out of it.. BTDT got no leaks..