l185 oil in coolant/coolant in oil

[freebird]

I thought I would post for assistance on this issue as I have been unable to solve on my own. I have browsed most all of the oil in coolant threads on here and have followed and checked most of the action items concerning this issue but have failed to ID the problem.
History of the repairs to date.
found coolant in crankcase, removed head, took to Kubota dealer for evaluation, the head was cracked, weld repaired the head and had it resurfaced. replaced #1 piston and rings (piston on radiator side) replaced head gasket. ran engine for approximately 20 minutes then oil showed up in radiator. remove head and installed the O ring I missed on the oil tube to head and re-used head gasket. re-assemble and run engine 20 minutes with the same condition, oil in the radiator, and a small amount of water in the crankcase. (< 5 oz of water) dis-assembled head purchase new head gasket and new oil tube O ring, stone cylinder block and head re-assembled ran engine 20 minutes with same condition. performed pressure test on radiator. pressure loss at 25 lbs is 2 psi in 1 minute, cold. pressure gauge is static while engine runs at 25 lbs on system. and 0 pressure lost on system after engine warms up after running 5 minutes. I will drop the oil pan today and pressurize the cooling system and see if I can locate the internal coolant leak. has anybody else has this issue? and does anybody have any ideas what else to check? I'm in a tight spot! thanks in advance for any feedback!

 

[D2Cat]

When you installed the head gasket did you use the thin shim that was with it?

 

[freebird]

The head gasket is OEM and there was only the single piece, no thin shim in the package, I dropped the oil pan and pressurized the coolant system, the coolant is getting into the crank case from around the crank shaft seals.

 

[North Idaho Wolfman]

I wonder if the water your seeing leaking is from water in the oil, in other words your pressurizing the coolant system and it's forcing water to where oil should be.
I would say you either have a warped headf, warped block, cracked block or still cracked head.
I personally would never weld a head, internal cracks can bleed coolant into the oil.

 

[freebird]

Thanks for the feedback, the head was sent out to a professional weld repair shop and they also decked the head, I was told this is fairly routine repair from the Kubota dealer. I suspect the problem maybe still in the head. what is confusing me is the oil in the radiator, it shows up pretty quick. I did check the block flatness with a straight edge and it was flat. I will pull the head again and send it back to be checked for cracks.

 

[Tooljunkie]

Oil pressure is instantaneous, where cooling syster has to get hot to raise pressure.
Need to make a pressure test plate, test block oil and coolant passages.

Head gasket repair may have not made the grade. Take it to a different engine machine shop and get it retested.

 

[Diydave]

Have you checked the freeze plug, front of block, above injector pump, behind the front gear cover??? That's what happened to mine, musta froze out, cause it was in the bottom of the gear cover, when I pulled it off...

 

[freebird]

Thanks for the info and feedback, I considered a block off plate for the head but not sure how to isolate the oil and coolant channels, and then how to test? I thought about using a piece of plexi glass and bolting it to the head, then pressurizing to 15 psi that way I could possibly see any leakage.

I haven't reached into the front gear case yet, the initial cause of the problem was a cracked head, and the change point was the weld repair and gasket replacement. that's when I started getting oil into the radiator, I am aware of the frost plug and also the cam plug that could cause water in the crankcase, not sure this would put oil into the radiator or not?

I will remove the head again and have it verified somehow. the voice in the back of my head keeps saying.... continuing to do the same thing over and over and expecting different results = insanity! Thanks again for the interest in this issue gentlemen!

 

[Diydave]

When I had the head off for crack checking, the machinists had a rig for pressure testing. Re the Freeze plug I mentioned, there are some water gallery holes, that come close to the FP, stick a big soft wire from the front gallery, probing, and feeling the front face of the block, toward the injector pump side. If the FP is out, you will feel a lip, then the wire will feed out the front of the block..

 

[freebird]

thanks for the feedback, I will try to probe the water channel and see if I can feel the void where the frost plug should be. I plan to remove the head in the next couple of days and have it checked again for cracks. I will keep this post active until this is solved.

 

[North Idaho Wolfman]

Sorry, but it highly unlikely that it's a freeze plug that is out, as that would just dump all the radiator into the oil pan.
Again highly unlikely, but it could be a leaking plug, that would hold pressure and water to a point.

Sadly I'm betting on a cracked block, as where you are getting a leak sound like a block crack.

Before you pull the head drain all the coolant and again pressurizer the radiator, if it's a cracked block you should hear an air leak after any remaining water is forced out.

 

[freebird]

Thanks for the feedback wolfman, unfortunately I yanked the head prior to draining the coolant. this is what I found; both pistons had no standing water on tops. I did probe the water jacket area on the piston closest to the radiator and noticed a 1" diameter hole that leads to the front gear case area. I was able to push a wire all the way through into the front gear case assembly without any restriction. I'm assuming there is no water cooling channels running through the front gear case area on this engine. I will try to pull an image of the block to see what this passage is for. I will also take pictures and post to the this thread. With such a large open passage I wouldn't think the coolant system would pump up and hold pressure, however... the oil system is a sealed system as well.... it took me about 4-5 strokes on the pump prior to building pressure in the system. I too would think such a big hole would dump the entire radiator into the crank case but... with the thermosypion cooling system no water moves until the water starts to boil, as there is no water pump. would this be a correct statement?

Thanks again for the feedback!

 

[Diydave]

Thanks for the feedback wolfman, unfortunately I yanked the head prior to draining the coolant. this is what I found; both pistons had no standing water on tops. I did probe the water jacket area on the piston closest to the radiator and noticed a 1" diameter hole that leads to the front gear case area. I was able to push a wire all the way through into the front gear case assembly without any restriction. I'm assuming there is no water cooling channels running through the front gear case area on this engine. I will try to pull an image of the block to see what this passage is for. I will also take pictures and post to the this thread. With such a large open passage I wouldn't think the coolant system would pump up and hold pressure, however... the oil system is a sealed system as well.... it took me about 4-5 strokes on the pump prior to building pressure in the system. I too would think such a big hole would dump the entire radiator into the crank case but... with the thermosypion cooling system no water moves until the water starts to boil, as there is no water pump. would this be a correct statement?

Thanks again for the feedback!

Correct on your understanding of the thermosyphon system. I suspect your and my tractor froze, at some point. Split the tractor at front, pull the gear cover, and see if the FP is in the bottom of the gear cover....

On edit, there is the return port for coolant, that goes straight through the cover, down the front, and out the lower hose. The FP I am talking about is almost in the right front corner, of the block, as viewed from operator's position. The outlet pipe is more toward the center, of the block...

About 10-12 hrs of work ahead of you, order a gasket set for the motor, and all the O-rings, under the gear cover. Hardest part is aligning the cover, for re-assembly, and re-attaching the governor spring, for the injector pump...

 

[North Idaho Wolfman]

freebird,
I'm curios what you find under the gear cover, It's just not adding up.
I will PM you a link for the download of the WSM for the L185.

 

[freebird]

I have attached a couple of pictures of the block and water jacket overall image and then a close up of the water jacket and round port that goes all the way through to the gear case. I have a hard copy of the WSM but all the images are black and white and doesn't show a clear view of the front of the block or any water passages. take a look and let me know what you think
Thanks

 

[freebird]

spent x mas and new years in the pole barn tearing my l185 to pieces, hoping to find the source of the water leak behind the gear case. I found the freeze plug intact and the cam plug intact! this will narrow down the possibility's of the source of coolant in the oil to either a cracked head or cracked block. Also a thanks to the wolfman for the WSM, it came in handy during the tear down.

 

[Diydave]

You might be able to figure out which side of the block has the crack, by draining the oil, removing both plugs, let all the oil drain out, for a day, then set 2 catch pans under both of the plugs, then fill the block with water, and seeing if one pan has water in it...

This will also let you figure out how fast the leak is...

 

[freebird]

Thanks for the idea, this might tell me what I need to know, I will try it when I put the gear case back together.

 

[freebird]

When you installed the head gasket did you use the thin shim that was with it?

Update... as it turns out the root cause of this issue was operator error! I missed the head gasket shim, its purchased separately from the head gasket. I will re-assemble and be a little wiser in my ways next time, thanks for everyone's help with this

 

[D2Cat]

Freebird, I am not sure you need that shim. I asked because you may have put in in there and it wasn't needed, and maybe THAT causes your problem.

Do some checking, but I think that shim is required when some machine work is done on the head or block, changing the dimensions.

You may NOT need it.