DK35 over heating

[jbain]

Hi all,

My DK35 is over heating within minutes of starting.

When/what happened: brush hogging, heard a squealing sound, the temp gage was in red and coolant boiling over reserve tank. Now it boils over (bubbles in reserve tank) within minutes when starting the tractor when cold.

Things checked: water pump OK, thermostat OK, coolant level is good at start, cleaned radiator, fan belt good.

I don't see any oil in the coolant.

No squealing sound now.

Exhaust is not colored.

Engine seems to have good power, starts right away and oil level is good.

Any ideas?

 

[ritcheyvs]

Is it truly overheating or could you have a blown head gasket? Measure the water temp at the top of the radiator when this happens. Try to determine if the bubbles are steam or exhaust gas.

What do you think caused the squealing? How do you know the water pump and thermostat are OK?

 

[JoelD]

Agree with ritcheyvs sounds like blown head gasket. Not sure how you could get water that hot that quickly? Check oil and see if milky

 

[jbain]

Is it truly overheating or could you have a blown head gasket? Measure the water temp at the top of the radiator when this happens. Try to determine if the bubbles are steam or exhaust gas.

What do you think caused the squealing? How do you know the water pump and thermostat are OK?

I believe you are correct the engine is not hot to the touch when the coolant reservoir is boiling over.

I took the thermostat out and put it in a pan of boiling water. After that I took the water pump off and visually checked it.

The squealing sound may have been the pressure escaping through the new found hole in the head gasket.

Thanks,

 

[jbain]

Agree with ritcheyvs sounds like blown head gasket. Not sure how you could get water that hot that quickly? Check oil and see if milky

see response to ritcheyvs. Thanks

 

[jbain]

I'm in the process of pulling the head at the point of taking the fuel tank out. Grrrrr!

 

[ritcheyvs]

Pulling a push rod head is not the worst job in the world but not one you'd want to do for grins. If possible, I'd recommend a compression check on all cylinders before pulling the head You need a diesel compression gauge (adapter or screws into glow or injector hole) because you should see pressures in the 400 psi range for a good cylinder. That test would verify a head gasket leak and identify which cylinder(s) are impacted. Keep all the push rods in order so they go back in their original locations. Check the head for flatness while its off; you may need to have it planed at a machine shop. I recall discussion long ago about improved MLS (multi-layer steel) head gaskets. That may apply (I don't know the vintage of your tractor).

 

[jbain]

Pulling a push rod head is not the worst job in the world but not one you'd want to do for grins. If possible, I'd recommend a compression check on all cylinders before pulling the head You need a diesel compression gauge (adapter or screws into glow or injector hole) because you should see pressures in the 400 psi range for a good cylinder. That test would verify a head gasket leak and identify which cylinder(s) are impacted. Keep all the push rods in order so they go back in their original locations. Check the head for flatness while its off; you may need to have it planed at a machine shop. I recall discussion long ago about improved MLS (multi-layer steel) head gaskets. That may apply (I don't know the vintage of your tractor).

Thanks for the recommendations. I have the head off. Didn't have to pull the fuel tank just had enough room after moving the wiring harness to get the valve cover off. I did not do the compression check but found moisture in the #2 cylinder so suspect it to be the leak point.

How do you check the head for flatness? I put a straight edge on it and could not see light but not that accurate.

Really didn't see anything wrong with the head gasket that was obvious. Is that normal?

I use a piece of cardboard with holes to keep everything in order.

My DK is a 2001 model. I looked up the price for a head gasket around $80 so I would assume it is a MLS gasket.

Again Thanks, Johnny

 

[ritcheyvs]

You check for flatness with a GOOD straight edge. There is a spec but I don't know what it is. If you have a good machine shop handy, recommend you have them check it with their tools. You should also check flatness across the top of the block but heads seem more vulnerable to warping. There is also a chance (hope not) that there is a crack in the head but they are hard to see. I would look hard to find the problem before just rebuilding with a new gasket. The lack of a visible blow-out in the old gasket suggests a warped or cracked head and a leaking cylinder will cause overheating and eventual damage.

I looked it up. The spec for flatness is 0.002 in.

Check private message.