Cylinder wall and head "erosion"?

[North Idaho Wolfman]

Where did the head come from?

If it was Kumar Bros, it's highly likely that the head or more specifically the valve seat could be your issue.
I got one from them and every valve leaked when it was news.

 

[speedy5966]

Ya, it was KB. That stinks! I even did some research, and most of what I found on them was good. I ordered a replacement steering shaft from them, and it failed. They sent me a new one, no questions asked. Didn't even want the old one back.

So what did you do? If that's my problem, I'll probably just lap my valves. I'd hate to be down while I wait for the exchange process to happen.

I didn't get a chance to do the wet test yesterday, maybe today.

 

[D2Cat]

I wouldn't lap the valves. Just contact KB and tell them your problem. They may be familiar with similar problems and quickly send another head.

But if you work on the head, you better get it right hand hope it works fine because, for sure, they're not responsible at that point.

Or find a head from someone else, like GrainFarmer and return this head for a refund.

 

[speedy5966]

Well, I haven't done the wet test yet, but now there's a new symptom. it doesn't want to shut off with the throttle pull. It does shut off, but I have to pull it as far as it will go, and it really tries to stay running after I pull up on it. Before, it died without even pulling it all the way up.

 

[Mark15]

Is there a simple way to test for leaking valves on the head while it is off the engine?

I am about to install a new KB head as well for the same engine as OP. I pushed the valves open and peeked at them with a flashlight, and the mating surfaces of the seats and valves all appear clean and smooth.

I tried flipping the head up side down and puddling some diesel in the valve recess with paper towels underneath. the puddles didn't seem to to leak through much if at all, but it was difficult to be certain because some of the diesel crept into the combustion cylinder through the gully between it and the valve recesses.

 

[Mark15]

Well, I haven't done the wet test yet, but now there's a new symptom. it doesn't want to shut off with the throttle pull. It does shut off, but I have to pull it as far as it will go, and it really tries to stay running after I pull up on it. Before, it died without even pulling it all the way up.

Sounds like its either still getting fuel from the injectors, or possible somewhere else, ie engine oil, etc.

 

[coachgeo]

.... now there's a new symptom. it doesn't want to shut off with the throttle pull. It does shut off, but I have to pull it as far as it will go, and it really tries to stay running after I pull up on it. Before, it died without even pulling it all the way up.

Mine does that too. I have to hard accelerate then pull her home to make her shut off. Eyes open to the solution you find and determination of why it does this

 

[D2Cat]

Mark15, you can set the head with the intake or exhaust up. Fill ports with diesel. Let it set overnight and see if you see any dampness on the valve faces. Then turn the other side up and repeat.

 

[speedy5966]

Seriously considering taking the old head in and having it tested for cracks. If good, put it back on. Tired of working on this d**n tractor. I got stuff to do!

 

[Daren Todd]

Mine does that too. I have to hard accelerate then pull her home to make her shut off. Eyes open to the solution you find and determination of why it does this

Pull the inspection cover on the side of the injection pump. More then likely the fuel rail is sticking. It's controlled by spring tension.

Soak the rail with pb blaster. Work it back and forth till it works good and smoothly. Then soak with some oil after to lube it up really good.


Sent from my iPhone using Tapatalk

 

[speedy5966]

Hate to dig up such an old post, but I finally have an update. I ran a wet/dry compression test, and got 240-260 dry, and 380-400 wet. A full rebuild kit with sleeves was around $700, and I figured at least another couple hundred for machine work, not to mention all the extra time. I found a used D850 with around 700 hours, for $1100, shipped. I figured that was pretty much a no brainer. New engine installed, and I can now run my brush hog in 3rd gear, without much effort from the tractor.
Thanks to everybody for all of the help and advice, I really do appreciate it!