Coolant Loss Mystery

Post your questions or problems you are haviing with your Yanmar tractor here.

Moderator: Aaron

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Coolant Loss Mystery

Postby tjrigario » Fri Dec 25, 2020 10:38 am

Greetings Folks,

I've got a JD 1050 that I recently did a head replacement on. The original had a hairline crack right by the injector port. I bought the fully built-out Hoye Tractor replacement head and it fit on perfectly without issue. I've put roughly 100hrs on the machine and have noticed that it's losing a bit of coolant that I can't seem to find a cause for. Other than that, it runs perfectly fine. After putting the pressure tester on, I'm finding it does lose pressure but there no visible leaks that I can see. It seems highly unlikely that the new head is yet again cracked...but I suppose it's technically possible. There are also no signs of any coolant in the oil and/or oil in the coolant. No exhaust gases are detected in the coolant either..so that pretty much rules out the head gasket in my mind. My only other thought is the cylinder sleeve o-rings, but I'd think I'd be seeing traces of coolant in the oil if those were going bad.

Any ideas?

My next thought was to do a compression and leak-down test on each cylinder.

winston
Volunteer Poster
Posts: 5735
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Coolant Loss Mystery

Postby winston » Fri Dec 25, 2020 11:29 am

Does it have the overflow bottle in place? Is that where you are seeing the coolant loss?

It is a long thread but should proove interesting to you. https://www.tractorbynet.com/forums/joh ... inion.html

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Fri Dec 25, 2020 12:28 pm

Yeah, there is an overflow bottle. That's where I notice the coolant loss. I'll top it up to the FULL line and notice that the level will be down a little after running it and letting it set overnight.

winston
Volunteer Poster
Posts: 5735
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Coolant Loss Mystery

Postby winston » Sat Dec 26, 2020 5:36 am

Have you watched the overflow bottle closely for signs of bubbles or removed the cap and watches for bubbles? If that proves negative and your satisfied there are no external leaks then it is going to be difficult to pinpoint an internal leak. Coolant leaking into the combustion area will cause white smoke but normally that would be from a larger leak. Coolant leaking from the sleeves should end up contaminating the oil. I have read where the 1050 heads are bad about cracking. I have rambled on without offering much help. Reading on this sight about the sleeve installation I see where depending on s/n the sleeves and head gasket might be different. Don't know if it could be possible your head gasket is wrong. https://www.hoyetractor.com/PROD/WS-1050.htm

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Sat Dec 26, 2020 5:30 pm

There are no obvious external leaks that I can find. No bubbles in the radiator or in the overflow tank. I think the next step is to pull pan and verify nothing is leaking internally during a pressure test. If nothing is found there, unfortunately pulling the head is going to be in order to see what's going on. My machine only has 800hrs on it, but the previous owner did overheat it and crack the head. I'm pretty sure everything is stock and I used the JD head gasket when I replaced the head...so one would think it's fairly fool proof, but it's hard to tell.

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Wed Dec 30, 2020 4:44 pm

To close the loop on this, I was able to find the leak. It is indeed leaking coolant internally from one of the sleeves. Looks like I'm in for a major engine overhaul. I've attached an image of the leak.

Long story short - don't overheat a 3T90-J engine. I can thank the previous owner for that.

IMG_8266.jpeg
IMG_8266.jpeg (42.16 KiB) Viewed 253 times

winston
Volunteer Poster
Posts: 5735
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Coolant Loss Mystery

Postby winston » Wed Dec 30, 2020 5:55 pm

Happy to see you found the leak. Got to be a little peace of mind just having that knowledge.

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Wed Dec 30, 2020 6:02 pm

You are very right about that. Now onto the fun part - tearing this engine apart!

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Sat Jan 09, 2021 4:45 pm

Well, I'm in the process of tearing into the engine and have just recently gotten the pistons out of the block. Upon inspecting the #2 piston, it's got some very unusual wear marks on the sides. There is no sign of rubbing on the sleeve, so I'm a bit at a loss as to what caused this. Overheating perhaps? Any ideas? I think I'm going to play it safe and replace the piston.
Attachments
IMG_8299.jpeg
IMG_8299.jpeg (222.36 KiB) Viewed 138 times

winston
Volunteer Poster
Posts: 5735
Joined: Mon Feb 01, 2010 7:29 am
Location: North East Texas

Re: Coolant Loss Mystery

Postby winston » Sat Jan 09, 2021 5:48 pm

wonder if the coolant could have been leaking into that cylinder from up top?

tjrigario
Volunteer Poster
Posts: 10
Joined: Mon Dec 31, 2018 12:30 pm

Re: Coolant Loss Mystery

Postby tjrigario » Sat Jan 09, 2021 5:55 pm

Could be. It's very odd. The crank journals look fine, so I'm not worried about an issue there. The only thing I can think of is it got so hot the oil on the side of the sleeves and caused a little bit of piston slap.


Return to “Tech Support”

Who is online

Users browsing this forum: No registered users and 29 guests