Kubota 1550 with a D850. I bought this non running, said it had been in a barn for a few years. cleaned the fuel system, lift pump, injection pump, new head gasket, new standard rings (liner walls seemed to be fine.). I getting 320 psi on each cylinder which was better than the 290 i was getting before ring replacement. it just seems odd that all three cylinders have the almost exact compression (320) Would it run at 320 psi ?
Kubota 1550 hst compression issue
- Thread starter Ronnie young
- Start date
First off is, WELCOME! 320psi should be enough to get the engine started and running. The compression pressures are to be between 337-448 psi. Have you tried to start the engine yet? With glow plugs, DON'T use starting ether spray. I have used a hot hair drier into the engine air intake to help it along with starting. I assume your valves are properly adjusted?
Thank you . Yes I have tried to start it. It does try with glow plugs but just cant seem to keep going. as far as i can tell the valves are right. I set them at .007 that is what i have read on google search. But that could be wrong
The engines can be a bugger to initially start. Are you sure you are bled out well on the injectors?
PARRALLEL, positive to positive and negative to negative, another battery to the tractor's battery from a car or truck with the car or trucks engine running and keep the starter engaged while it is trying to start. This will give you maximum starting current and voltage. Be sure not to overheat the starter but you will have to give it a workout. Add a bit of throttle when it is trying to start. .007" is a good clearance on the valves. Try a hair drier on full hot into the intake while trying to start the engine. You might need a helper to hold the hair drier.
I accidentally ran my D650 Kubota engine on an ONAN generator, out of fuel. It was a bugger to get bled out and re-started. I had to repeatedly crack the injector unions at the injectors to get all of the air out. While trying to bleed out your injection system, open your throttle.
PARRALLEL, positive to positive and negative to negative, another battery to the tractor's battery from a car or truck with the car or trucks engine running and keep the starter engaged while it is trying to start. This will give you maximum starting current and voltage. Be sure not to overheat the starter but you will have to give it a workout. Add a bit of throttle when it is trying to start. .007" is a good clearance on the valves. Try a hair drier on full hot into the intake while trying to start the engine. You might need a helper to hold the hair drier.
I accidentally ran my D650 Kubota engine on an ONAN generator, out of fuel. It was a bugger to get bled out and re-started. I had to repeatedly crack the injector unions at the injectors to get all of the air out. While trying to bleed out your injection system, open your throttle.
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Will it run now? Run it at 1500 rpm (+-) and vary the engine speed. Try to drive it for a while and vary the RPM. Glad the heat gun worked. Hopefully when it is broke in, in a few hours run time, it will start on its own. Keep me posted. Change your oil and filter after 3-5 hours of run time. NO synthetic oil for a while.
Ronnie, how is the engine running now? Will it start on just glow plugs and run okay?
Haven't heard back from you on the site. It helps others when you report back.
Sorry for the delay, just been busy. yes fires right up with glow plugs. Thanks again. I do have a question. I have a bad head bolt D850. Do you happen know the bolt thread and size.?
Glad to hear it is starting well. I don't know the size and thread pitch of the D805 head bolt.
What's wrong with the head bolt?