CT225 head gasket?

   / CT225 head gasket?
  • Thread Starter
You have said nothing about replacing the thermostat, did you do that?

Do you have a Auto Supply close by or another auto parts location that rents tools. If so rent a radiator pressure tester and test the cooling system. Dyes are not a good indicator tester for a internal leakage problem.

The pressure tester is simple to use. Remove the radiator cap install the cap on the pressure tester on the radiator make sure it is tight and making a good seal. Pump the pump until the gauge shows fifteen psi. Stand by and watch the gauge and listen for escaping air and look around the outside of the cylinder head for signs of moisture. If the gauge goes down or does not hold the 15psi you have a internal problem. Also check your engine oil for signs of moisture.

If mine I would not be doing any test runs or using until I located the problem. A new engine is expensive.

Also the unit is made to run with the radiator cap installed and tightly closed. That is the reason for the overflow tank. It allows for the system to be closed and not contain air or air pockets. Air or excessive expansion fluid is vented into the tank when hot. As the engine cools the fluid is sucked back into the radiator.

Bottom line and this is just an opinion on my part and based on the sandy colored substance you have discovered is the unit has been run with either a pure water mixture or wrong anti freeze and the internal coolant passages in either block or head has been degraded.

Diesels with what is called wet cylinders require a anti cavitation anti freeze. I use anti cavitation Anti Freeze in all my diesel units. Tractor Supply or other Anti Freeze suppliers in my area sells the product.

I did not replace the thermostat, it was on my radar but when I saw the water circulating and the temp gauge moving, I assumed it was functioning. Is my logic flawed?

I have been looking for an excuse to buy a pressure tester, so I picked one up on the way home. I pumped her up to 16psi at 5pm and didn't get back out to check on it till after 9pm, it was dead nuts on 16psi!

I did check the oil and have continued to do so, not just for a milk shake, but also looking at the level incase the water is finding a way to the bottom of the pan without mixing.

I did run it for a few hours last weekend and it ran well, the temp seemed to creep up when driving. I am a home owner and if I am honest, this is going to live a easy life. I put about a mile of street driving on it between the two houses. I used the tractor to move logs and clear some ground. I thought it was odd that the temps stayed reasonable while working the machine, but creeped up to all but the red when just driving it. We are talking 2,000 RPM in M, on hilly pavement.

Since I flushed the cooling system, it has been functioning as prescribed. What makes me nervous is overflow constantly bubbling / boiling when it runs. That is why I tested the coolant with the chemical test 900 times. I am hoping that the bubbling / boiling is normal or that it's an indication the radiator cap isn't functioning properly. I assume the thermostat and the water pump are okay because when I shoot the block and radiator with an IR temp gun, it's never over 160 and I can see the temp creep up and then the back down.

I used Shell 9404106021 Rotella ELC Antifreeze, it's listed as having "cavitation protection", not sure if that the same thing. It's
   / CT225 head gasket?
  • Thread Starter
It sounds like the tractor is new to you is the sandy sludge in the overflow tube stop leak that the previous owner put in trying to remedy the same problem?

Yes, that's my fear too. I don't want to believe it nor do I want to sell it to the next guy without knowing it's "good to go". I'd rather fix a head gasket and know it's good than assume that the mystery substance I found was not a crummy patch to hold it over just long enough for the next guy to buy it.
   / CT225 head gasket?
  • Thread Starter
   / CT225 head gasket? #14  
If that is a photo from your expansion tank, if mine I would pull the radiator and take it to a radiator shop and have them to clean it. That is a lot of gunk floating around in a radiator.
   / CT225 head gasket? #15  
Bubbling/boiling is not normal. Sure sounds like a leaking head gasket. There is lot's of pressure in the cylinders when she's running. Way more than the 16 lbs you tested.
   / CT225 head gasket?
  • Thread Starter
If it needs a headgasket, I am not sure I am up for the job, I'm just spread too thin right now. My local "Bobcat" dealer is a Best Line. Should I take it to them?
   / CT225 head gasket? #17  
I am not declaring your head gasket is bad so don't move to fast on my thoughts. Will go on to say your temperature should not be creeping up as you stated in post #11. Crank it with the cap off when cold and see if you have a constant stream of bubbles in the radiator.
   / CT225 head gasket?
  • Thread Starter
I plugged up the overflow cap with the tester at zero psi. Within a minute or so it shot the gauge up to 25psi. The top hose started leaking from the pressure but the engine was still cool. What other than a head gasket would cause a constant stream of bubbles in the coolant when it runs?


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   / CT225 head gasket? #19  
I suppose a cracked head, however, I would say large percentage would lean toward head gasket. Either way, the head has to come off. Once again, on my part, long distance diagnosis on my part is to be taken as opinion only and not fact.
   / CT225 head gasket?
  • Thread Starter
Hello all, just wanted to follow up. I put the tractor up for a little to deal with other projects, I bought this only because I assumed it would not be another one.....

I pulled the head off last Friday and boy, I was not happy to see the water passages blocked by the headgasket in a can. See images below.

My plan:
  1. Pull the radiator and see if the local radiator shop thinks they can clean it up for me
  2. Take the old head gasket and bolts to the Kioti dealer near by and verify the gasket and bolts they held form me match
  3. Pick up any additional gaskets I need like the water pump, intake and exhaust gaskets
  4. Pickup a set of long bottle brushes to clean out as much of this BS miracle head gasket elixir out of the engine
  5. Clean, Clean, Clean everything. At this point the fuel system, oiling system, cooling system in one way is open and I need to used compressed air and mechanical means to clean the passages as best as I can
  6. Bring cleaned head to work and check if for warping on a surface plate (I work at a machine shop)

My fear is the little bits of this grit I can't remove will "re-activate" and form new blockages in the system. I don't know if the stuff left behind is already "activated" or if it can react the way it did originally time and time again.

I can't imagine I am the first person to encounter this much head gasket in a can sludge, someone out there has been through this before!