Kubota - Will Not Turn Over

[Scare_Rab]

Bought the boat 2 weeks ago - 3 x cylinder Kubota will not turn over.

Boat has been sitting without moving for some years.

My diesel engine knowlege is between 'fair' & 'poor' - I'm not mechanically illiterate --- I did completely re-build an 860 cc Ducati 4-stoke motorcycle half a life-time ago.

I paid a diesel mechanic $80 yesterday.

He came on board and spent 30 mins trying to turn the engine over:

He took out the injectors, then tried many and various combinations of "Big spanner on the big nut on the end of the fly wheel"

He grunted a lot. Looked a pretty strong guy.
Seemed like lots of force was being applied.

but no movement.



He rang his Boss.
The only suggestion was "take the head off".
... or
"we can sell you a re-conditioned one for $13,000"

He left

Hmmm

Previous owner stated "nothing bad happened to motor- just did not get used".

Perhaps one cylinder or more is stuck to the barrell / sleeve?

? would taking the injectors out again and filling the chamber with diesel help? or would WD40 be better? or some ting else? (Then wait some days and try turning over agin?)

Questions /comments / suggestions welcomed

Any suggestions?

[DeepFrz]

Well, you might try that. Get a good penetrating oil and spray some into each cylinder. Leave for a few days and then try turning it over. You might get lucky. It was in neutral, right?

Oh, and next boat you buy, run the engine. Better yet have an engine surveyor check it out for you.

[speciald@ocens.]

Pull the injectors, spray PB Blaster into the cylinders and let it sit for a few days, then try to turn the crank by hand.

[Sailmonkey]

Try the penetrating oil first, spray a bunch in each cylinder, let it sit for a day or two, try to turn with a wrench on the front pulley of the engine. If it doesn't turn after this, just take the head off. there isn't a lot of skill needed to take the rockers off then pull the head. you should be able to see right away what the problem is at that point.

[Stillraining]

What they say about the injectors and oil in the cylinders.

But Id do one more thing before pulling the head.

Build what ever adapter you need to to engage any holes that may be in your crank pulley, your crank pully bolt can not handel the loads for this...I am attaching a picture of one I made to fit an engine with a big nut welded on it that will take the torque....then get yourself a 3 to 4 foot long 3/4 or 1" drive breaker bar and socket ( you can rent one) and literally jump with all your weight on it and try to break the pistons free from the cylinder walls....you have absolutely nothing to loose doing this as its better then 85% chance you will break them free and with an additional hours work rotating the engine and squirting regular 10 40 oil in the cylinders getting it freed up and easier to spin she will fire right up for you.

I have done this exact procedure on 3 different seized up engines and have not had to tear into any of them...and they all still purr like kittens....and burn zero oil.

Think about it...what are you going to do once you pull the head?...your going to beat on the pistons that what your going to do...my way is way less aggressive when you think about it...no smashed bearings or broken pistons tops...same risk of cracked rings or broken ring glands with scored cylinder walls...Im willing to bet 100.00 it works for you.

[Scare_Rab]

What an awesome idea!

Build the adapter I need to to engage any holes in my crank pulley...

then have at it with a big bar!

= the Power of the INter Web....

Thanks people



a bloke here at the Marina also suggested :

removing the Tappet cover and cracking the exhaust valve open ---
So that I will not be fighting the compression when trying to turn it over
.
.

[boden36]

I have not tried this , but it may work in conjunction with your other efforts.
Circulate hot water through your engine's water cooling system or perhaps use a hot air gun. The aim is to warm the cylinder walls slightly and maybe cause some expansion and thus loosen whatever is locked.
Regards, Richard.

[svrodeorm]

good advice you've got there already.

Especially the one suggesting running the engine before buying the boat.

Guess you go it dead cheap on an auction or...

and don't forget to tell us how it goes from here! with pics- lots of pics!

[Boracay]

Just to check, we do know that if the injectors are removed there is no need to fiddle with the exhaust valve to make sure there is no compression. So do all this with injectors removed. Be careful that spray from the injectors cannot hit your skin or eye - can cause gangrene.

Rather than use a big single force (and maybe pull a muscle or worse) I'd (using the adapter if possible and after letting soak in whatever penetrating oil you go for - the ones mentioned sound good) start by rocking the "lever" gently back and forward. Even very tiny movements will help to break the bond between the rings and the cylinder wall. It may not take much force but it may take quite a while.

After you get the engine started I'd suggest changing the oil immediately.

[shakey doug]

A head gasket for a 3 cyl kubota costs around the same as carton of beer why would you risk further damage with over sized bars etc? Remove the head for a true evaulation your duke experience makes you more than capable. $13000 for a reco engine someone is pulling your tit, you can buy a new industrial engine and swap all marine parts over for a fraction of that price. Are you in Aussie?

[Healer52]

Originally Posted by Scare_Rab

What an awesome idea!

Build the adapter I need to to engage any holes in my crank pulley...

then have at it with a big bar!

= the Power of the INter Web....

Thanks people



a bloke here at the Marina also suggested :

removing the Tappet cover and cracking the exhaust valve open ---
So that I will not be fighting the compression when trying to turn it over
.
.

Pull the injectors. Fill the cylinders with liquid wrench, marvel mystery oil, PB blaster, or some other penetrating oil. let it sit for a day or two.

Then, without replacing the injectors, try turning the engine over. With the injectors out, you won't have any compression (if you do, you have other serious issues). If you can then turn the engine over, replace the injectors and try starting. If not, rebuild the engine.

[Stillraining]

Originally Posted by Scare_Rab

a bloke here at the Marina also suggested :

removing the Tappet cover and cracking the exhaust valve open ---
So that I will not be fighting the compression when trying to turn it over
.
.

You will already have your injectors out to squirt the oil in...so no need to do this at all.

[Tellie]

Not sure of the valve to piston clearance on you particular engine. But if rust is what has your pistons stuck it could possibly have your valves stuck open as well. At this point as stated earlier a head gasket is cheap enough. Pull the head then work to turn your engine over. There's also the possibility of hydro lock in which case you might do more damage. Also if you were qouted 13K for a re-built, find someone else to work on your engine.

[Stillraining]

No risk hydro lock dammage with injectors pulled.

If you want to pull the valve cover and watch the valves while your turning go for it...but there is no reason to pull the head yet.

[Charlie]

I have heard that transmission fluid is really good to pour in a an engine to loosen stuck parts. Never tried it but heard it from a really good mercedes mechanic.