The 1964 MF-135 diesel is overheating

[flusher]

Engine is overheating after about 10 minutes of operation. Coolant coming out of the radiator overflow. Temp gauge in the red.

I thought the crud on the radiator that was severely restricting the airflow was the cause. Cleaned the radiator thoroughly. Checked airflow with a piece of paper. It was sucked firmly to the fins across the entire radiator so I don't see any airflow restriction.

Replaced the thermostat and the temp gauge. Can see the thermostat open by watching the gauge. So that seems OK.

Can't see any water flow with the radiator cap off and the thermostat open.
With the engine off, tugged on the fan belt to see if the water pump bearing is bad. Couldn't get the belt to move, so it looks like the bearing is OK. No leakage visible around the water pump shaft or engine seal.

Anyone out there know a good way to backflush a Perkins diesel? The backflush kits at the auto parts stores are set up to splice into one of the heater hoses. No heater hoses on the MF-135.

Could be a bad head gasket. Anyone out there used one of those $25 combustion gas leak testers (the ones with the liquid that changes color in the presence of carbon monoxide, etc. exhaust gases in the coolant system)? Are they any good?

 

[DieselPower]

Not familiar with your tractor, does the Perkins have a water pump or is it a thermal type gravity cooling system?

If it has a water pump it could be bad. The fins can rust off of the pump leaving you with reduced water flow. It could also be a pluged up radiator. I have had very good luck with Prestone cooling system flush before. I use their professional type that is a acid type cleaner. One end of the can has the acid cleaner powder in it and the other end of the can has the acid neutralization powder in it. If you want to give this stuff a try I would be happy to send you one, I think they cost me around $2.50 a can when I got my last 2 cases of it.

The combustion gas leak testers do work. I have a Snap On one I bought years ago and have used it many times to find leaking head gaskets. It's so sensitive the blue fluid will turn yellow just by you breating into it. Do you think the head gasket may be leaking? If it is with the radiator full and the engine running you will probably see bubbles.

 

[flusher]

Not familiar with your tractor, does the Perkins have a water pump or is it a thermal type gravity cooling system?

If it has a water pump it could be bad. The fins can rust off of the pump leaving you with reduced water flow. It could also be a pluged up radiator. I have had very good luck with Prestone cooling system flush before. I use their professional type that is a acid type cleaner. One end of the can has the acid cleaner powder in it and the other end of the can has the acid neutralization powder in it. If you want to give this stuff a try I would be happy to send you one, I think they cost me around $2.50 a can when I got my last 2 cases of it.

The combustion gas leak testers do work. I have a Snap On one I bought years ago and have used it many times to find leaking head gaskets. It's so sensitive the blue fluid will turn yellow just by you breating into it. Do you think the head gasket may be leaking? If it is with the radiator full and the engine running you will probably see bubbles.

Yes, the Perkins diesel has a water pump.
I have some of that radiator flush and plan to try it later this week.
Thanks for the info on those testers. I've ordered one from Amazon.com. Should be here by Friday.

 

[Soundguy]

I'd think you would have considerable combustion bubbles in the radiator with the cap off if enough gas was passing into the coolant to superheat it.

First.. i'd pull the radiator hoses off and do a flow test onthe radiator... a good ratiator should flow all the water from a 1/2" garden hose.. stick the hose in t he top of the rad.. turn it on.. it it overflows at the top.. it's plugged.

Also.. see what comes out.. if you get lots of sediment and gunk out.. you know you are seeing the cause.

Some people even try to backflush the block this way by putting a water hose tot he inlet and letting it flush. That's hit or miss based on the flow of water you have.. and the particular engine.

You can check the water pump by removing the thermostat and then filling the radiator, and pulling the top hose off and aiming it into a bucket..

Post back what you find.

Soundguy

 

[Farmwithjunk]

I wouldn't go as far as to call it a weak link, but one thing that has a higher failure rate on the Perkins diesel is the water pump. They've been known to fail every 40 or 50 years under normal service Check impellors.

 

[flusher]

I'd think you would have considerable combustion bubbles in the radiator with the cap off if enough gas was passing into the coolant to superheat it.

First.. i'd pull the radiator hoses off and do a flow test onthe radiator... a good ratiator should flow all the water from a 1/2" garden hose.. stick the hose in t he top of the rad.. turn it on.. it it overflows at the top.. it's plugged.

Also.. see what comes out.. if you get lots of sediment and gunk out.. you know you are seeing the cause.

Some people even try to backflush the block this way by putting a water hose tot he inlet and letting it flush. That's hit or miss based on the flow of water you have.. and the particular engine.

You can check the water pump by removing the thermostat and then filling the radiator, and pulling the top hose off and aiming it into a bucket..

Post back what you find.

Soundguy

SG:
Here's the skinny:

Garden hose full blast with radiator bottom hose disconnected--

Result: get good flow out of the bottom of the radiator; some overflow at the top of the radiator. No sludge or sediment came out of the radiator.So the radiator can't take the full flow from that garden hose.

Thermostat removed, radiator bottom hose connected, radiator top hose disconnected at the radiator, radiator filled with water until it flows out of the top radiator hose (that's connected to the outlet of the water pump)

Result: water pump produces lotsa flow out of the top hose. Pump empties the radiator in 4-5 seconds. So the pump looks OK to me.

One thing: before I drained the coolant out of the radiator to start this troubleshooting work, I opened the coolant drain on the engine block. Got nothing flowing out of the block. I expected at least a trickle of coolant. Wonder if there's blockage in the coolant passages in the block.

Anyone ever backflushed a diesel engine on a vehicle with no heater hoses?

 

[machmeter62]

SG:
Here's the skinny:

Garden hose full blast with radiator bottom hose disconnected--

Result: get good flow out of the bottom of the radiator; some overflow at the top of the radiator. No sludge or sediment came out of the radiator.So the radiator can't take the full flow from that garden hose.

Thermostat removed, radiator bottom hose connected, radiator top hose disconnected at the radiator, radiator filled with water until it flows out of the top radiator hose (that's connected to the outlet of the water pump)

Result: water pump produces lotsa flow out of the top hose. Pump empties the radiator in 4-5 seconds. So the pump looks OK to me.
FLUSHER: Was the engine operating upon purchase? If so, did you operate it long enough to get it up to normal temp. before the restoration started? Are you the only one doing the maintenance? This might help the guys here with more info?

 

[flusher]

SG:
Here's the skinny:

Garden hose full blast with radiator bottom hose disconnected--

Result: get good flow out of the bottom of the radiator; some overflow at the top of the radiator. No sludge or sediment came out of the radiator.So the radiator can't take the full flow from that garden hose.

Thermostat removed, radiator bottom hose connected, radiator top hose disconnected at the radiator, radiator filled with water until it flows out of the top radiator hose (that's connected to the outlet of the water pump)

Result: water pump produces lotsa flow out of the top hose. Pump empties the radiator in 4-5 seconds. So the pump looks OK to me.
FLUSHER: Was the engine operating upon purchase? If so, did you operate it long enough to get it up to normal temp. before the restoration started? Are you the only one doing the maintenance? This might help the guys here with more info?

I purchased the 135 in July 2006. The plastic window on the temp gauge, which likely was the factory original, had deteriorated so much due to sunlight that it was impossible to see the pointer on that gauge. So I don't know if that gauge was operational.

I ran the engine 3 or 4 times for ten minutes or so each time during the next two months until I parked it last Oct. The last time I ran it I noticed that coolant was coming out of the radiator overflow and that the engine was running hot. I figured this was due to all the crud on the radiator fins obstructing more that half of the airflow thorugh the core and that this problem would go away once I detailed the radiator.

I pecked away at the restoration (thorough cleaning, rewiring, repainting, normal servicing with fluids change) and finally finished it last week. I was plesantly surprised when the engine fired right up after sitting for nearly 9 months. Thought I was home free and took the 135 for a spin to see if all the new gauges worked (I replaced all of the gauges except the fuel gauge/sender, which worked OK).


I drove the tractor around my place for 10 minutes or so and noticed that the new temp gauge acts funny. I expected it to show a steady rise in temperature while the thermostat was closed and then a drop in temperature after the thermostat opened. Instead the temp gauge stayed pegged on the left end of the scale (cold) for 3 or 4 minutes and then jumped upscale into the low end of the normal range (the gauge only shows cold, normal and hot, not degrees F). The gauge continued to show increasing temp until it entered the hot range at which time coolant started to come out of the radiator overflow. Total time about 10 minutes after engine cold start. Don't know yet what this is telling me.

There's no possibility that the thermostat is installed backward because the thermostart housing only permits installation one way, with the spring end of the thermostat pointing down (i.e. toward the engine block and away from the radiator). I verified, using Soundguy's suggestion, that flow from the water pump outlet is directed into the upper radiator hose through the thermostat.

So the status now seems to be this: the water pump looks OK. The water passages in the radiator core may be somewhat clogged, but don't know yet if this is causing the problem. The thermostat operates OK (opens in the 170-180F range) and is installed correctly. Using 50/50 antifreeze mix. No flow out of the coolant drain in the block. No black, white or blue exhaust smoke out of the muffler. No indication of exhaust contamination in the coolant.

 

[Soundguy]

The no flow out of the coolant drain in the block is a puzzler... Unscrew it and see if the block may be packed with sludge.

Soundguy

 

[flusher]

The no flow out of the coolant drain in the block is a puzzler... Unscrew it and see if the block may be packed with sludge.

Soundguy

OK. But the drain is in there tight. Gonna take a while for PB Blaster to work on those threads.