Coolant in Oil

[WilliamTO-35]

I've been using my 1955 Ferguson TO-35 with the Z134 gas engine for 35 years now , with no unusual engine problems. At the end of last winter, however, I was pushing some snow and steam started pouring out of the radiator cap. I parked the tractor and shut it down within about 30 seconds. When the engine cooled, the radiator was about a gallon low on coolant. I assumed there were radiator leaks, although I never found any significant leaks. When I changed the engine oil this summer, I found about a half pint of coolant in the engine oil. I've only run the tractor at idle for about 20 minutes since I found the coolant in the oil, but it's too late in the season to do any repairs. I put some stop leak in the radiator, and I'm leaving the radiator cap loose , hoping that I can make it through the winter . Next spring, I'm expecting to find a blown head gasket , but often on an older engine there's more damage than you expect. I removed the spark plugs and cleaned them, with no indication of any one cylinder getting coolant into the combustion chamber. There's no white smoke coming out the exhaust at idle. This engine has wet cylinder liners, so coolant could be getting in through the lower sleeve seals. What's the most likely damage I'll find on this engine? Could I be lucky, and just find a blown head gasket, or is it likely the overheating caused more complicated problems ? If I need to plow snow with the tractor this winter, I plan to keep an eye on the engine oil, and if I start finding more coolant, I'll just have to stop using the tractor entirely until I tear it down.

 

[Jerry/MT]

I've been using my 1955 Ferguson TO-35 with the Z134 gas engine for 35 years now , with no unusual engine problems. At the end of last winter, however, I was pushing some snow and steam started pouring out of the radiator cap. I parked the tractor and shut it down within about 30 seconds. When the engine cooled, the radiator was about a gallon low on coolant. I assumed there were radiator leaks, although I never found any significant leaks. When I changed the engine oil this summer, I found about a half pint of coolant in the engine oil. I've only run the tractor at idle for about 20 minutes since I found the oil in the coolant, but it's too late in the season to do any repairs. I put some stop leak in the radiator, and I'm leaving the radiator cap loose , hoping that I can make it through the winter . Next spring, I'm expecting to find a blown head gasket , but often on an older engine there's more damage than you expect. I removed the spark plugs and cleaned them, with no indication of any one cylinder getting coolant into the combustion chamber. There's no white smoke coming out the exhaust at idle. This engine has wet cylinder liners, so coolant could be getting in through the lower sleeve seals. What's the most likely damage I'll find on this engine? Could I be lucky, and just find a blown head gasket, or is it likely the overheating caused more complicated problems ? If I need to plow snow with the tractor this winter, I plan to keep an eye on the engine oil, and if I start finding more coolant, I'll just have to stop using the tractor entirely until I tear it down.

I don't want to be an alarmist, but the Z series Continentals are prone to cracking. It's particularly true for the Z-129. That said, I've not heard of a endemic cracking problem on the Z-134.
Overheating can be caused by a loose fan belt, clogged air side on the radiator, clogged coolant passages in the radiator, stuck closed thermostat, collapsed lower rad hose, corroded pump impeller, overly lean mixture etc. . This could have caused the head to warp and/or the head gasket to blow. With the engine running at operating temperture, if the head gasket is blown, you may see bubbles in the coolant. Have you noticed any additional coolant in the crankcase? If not, you may have lucked out by shutting down so quickly. As you imply, the other possibility is that the o-ring sleeve seals at the bottom of the sleeves are cracked and leaking.

You're taking the right steps to get through the winter. Do you have a temperature gauge? If so carefully monitor that during operation.

However you need to find out the cause of the over heating. If you have a rotary cutter and mow with it, it's quite posible that the air side of the rad is blocked. Check the thermostat for opening, make sure the fan belt is correctly tensioned. With the engine at operating temperature, observe the lower rad hose at idle and at max rpm to make sure it doesn't collapse. Make sure that your carb's power jet screw is not open any less than one full turn.

When the tractor is not critially needed, I'd screw the rad cp back on and operate the tractor normally to see if there are any problems. As I said, you may have lucked out.

 

[Don87]

I don't want to be an alarmist, but the Z series Continentals are prone to cracking. It's particularly true for the Z-129. That said, I've not heard of a endemic cracking problem on the Z-134.
Overheating can be caused by a loose fan belt, clogged air side on the radiator, clogged coolant passages in the radiator, stuck closed thermostat, collapsed lower rad hose, corroded pump impeller, overly lean mixture etc. . This could have caused the head to warp and/or the head gasket to blow. With the engine running at operating temperture, if the head gasket is blown, you may see bubbles in the coolant. Have you noticed any additional coolant in the crankcase? If not, you may have lucked out by shutting down so quickly. As you imply, the other possibility is that the o-ring sleeve seals at the bottom of the sleeves are cracked and leaking.

You're taking the right steps to get through the winter. Do you have a temperature gauge? If so carefully monitor that during operation.

However you need to find out the cause of the over heating. If you have a rotary cutter and mow with it, it's quite posible that the air side of the rad is blocked. Check the thermostat for opening, make sure the fan belt is correctly tensioned. With the engine at operating temperature, observe the lower rad hose at idle and at max rpm to make sure it doesn't collapse. Make sure that your carb's power jet screw is not open any less than one full turn.

When the tractor is not critially needed, I'd screw the rad cp back on and operate the tractor normally to see if there are any problems. As I said, you may have lucked out.

I'll have to respectfully disagree.

Coolant in the oil is cause for alarm. It can and will 'wash out' the main bearings and that engine will lock up. It's not a matter of "if it will" its a matter of "when it will".

Personally, I would not run that engine untli it is repaired.

Liners could have holes in them also (cavitation), allowing coolant into the oil.

 

[banjodunn]

G'day not sure if it is the same engine but seem to remember an alloy casting plug in the top of the head that had a habit of corroding out, IIRC the part is threaded into the head and is nla, if it is only a pinhole i have seen then drilled and tapped to take a 1/4 bolt with a fibre washer. You will have to remove rocker cover to see it. I would try a good leak sealant first if you do not have the time to fix now BUT i would be keeping a very close eye on both water and oil every time you use it


Jon

 

[WilliamBos]

I'll have to respectfully disagree.

Coolant in the oil is cause for alarm. It can and will 'wash out' the main bearings and that engine will lock up. It's not a matter of "if it will" its a matter of "when it will".

Personally, I would not run that engine untli it is repaired.

Liners could have holes in them also (cavitation), allowing coolant into the oil.

I agree totally. Only a matter of time now.

 

[Jerry/MT]

I'll have to respectfully disagree.

Coolant in the oil is cause for alarm. It can and will 'wash out' the main bearings and that engine will lock up. It's not a matter of "if it will" its a matter of "when it will".

Personally, I would not run that engine untli it is repaired.

Liners could have holes in them also (cavitation), allowing coolant into the oil.

I've.never heard of a gas engine having cavitation damage to liners.

 

[Don87]

I've.never heard of a gas engine having cavitation damage to liners.

I've never heard of anyone recommending running an engine with coolant in the oil.

 

[WilliamTO-35]

Thanks all for your advice. If I keep finding coolant in the oil, then I'll definitely park the tractor . Whatever damage occurred to cause this problem no doubt occured during the brief overheating episode last winter. It's possible that coolant will only get into the crankcase during an overheating episode. It's also possible that the radiator stop leak might plug up the source of the leak, or that running with the radiator cap loose will eliminate the problem. Sure, I'd have to be lucky for the coolant leak to disappear for the above reasons, but I don't run the tractor very often, and if I don't have to tear down the engine, I'd rather not. I also have a front loader which makes access to the engine more difficult. At this point, I plan to run the engine for only half hour periods before I check the oil again. If there's more coolant in the oil, then I'll have to park the tractor until spring. This tractor is my main snow mover during the winter. However, I bought a walk behind snowblower last season, and I may have to rely on that for snow moving this winter.

 

[boomer1025]

Thanks all for your advice. If I keep finding coolant in the oil, then I'll definitely park the tractor . Whatever damage occurred to cause this problem no doubt occured during the brief overheating episode last winter. It's possible that coolant will only get into the crankcase during an overheating episode. It's also possible that the radiator stop leak might plug up the source of the leak, or that running with the radiator cap loose will eliminate the problem. Sure, I'd have to be lucky for the coolant leak to disappear for the above reasons, but I don't run the tractor very often, and if I don't have to tear down the engine, I'd rather not. I also have a front loader which makes access to the engine more difficult. At this point, I plan to run the engine for only half hour periods before I check the oil again. If there's more coolant in the oil, then I'll have to park the tractor until spring. This tractor is my main snow mover during the winter. However, I bought a walk behind snowblower last season, and I may have to rely on that for snow moving this winter.

The best way to check for coolant in the oil is to let the tractor set over-nite and crack the oil pan plug and see what comes out first. Coolant or oil.

 

[Johnp33]

The only stop leak product I ever use is the silver flakes in the plastic tube. You can get corrosion that will eat threw a casting or more likely an internal frost plug, normally in the head.
Removal of the valve cover and the oil pan and pressurise it when cold will find the leak. It will not get cheaper or magically heal itself.
Just a thought!