Kubota - Will Not Turn Over

[Chief Engineer]

Yes cranking speed is most important

[Scare_Rab]

3 x cylinder Kubota

Hmmm

Bought a new "starting battery" this morning

Cranks over nicely - sounds as if it just might fire - but does not.

I took the fuel line from the filter and put it into a bottle of NEW diesel
(hoping --- The electric fuel pump will pick that fuel up just fine )

I'm now wondering ...

does this motor have some mechanical/electrical method of "Stopping it"

= some method that is currently "ON and needs to "OFF" before it will start?

I can see no levers/ cables / switches --- but what do I know?

Suggestions / comments ?

__________________________________________________ __

also the throttle cable (Morse) was stuck/immobile.

I hung it vertically, made a little cup of plasticine and soaked WD40 down it.

Freed it enough so it moves - just - moves with a big shove.
When I hooked it back up the the throttle lever - that movement was not good enough.

I can move the engine end of the cable by hand tho - - which I thought would be "good enough to start it"

? question - to start; where should the arm the cable pushes be ?

• - fully foward
• - fully aft -
• mid way -
• doesna matter?

...

[Stillraining]

All diesels have a fuel shut off...its the only way to really kill them conveniently

On your engine your fuel shut off IS your throttle cable if Im not mistaken...shoving the linkage all the way forward cuts off the fuel..whatever direction of your throtel handel that is...normally the same way...so in order to restart you have to open the throtel back off the fuel cut off position...If you don't have a cable attached..the spring loaded linkage will keep the linkage in the fuel cut off position..and it will not start...its a run a way engine safety feature.

[osirissail]

- - You said that the engine had a decompression lever - that is how the engine is stopped.
- - You said you were getting diesel spray from the injectors in an earlier post.
- - You said that the new battery spun the engine with the decompresson lever closed.
- - It sounded that you had sufficient compression but a compression tester would be useful to be sure.
- - Basically two things are left - Fuel supply to injector pump and fuel injection pump "out of timing." For the first one disconnect the fuel supply line line somewhere between the fuel pump and the injection pump and rotate the engine. You should get a good fuel flow out of the pipe to prove the fuel pump is working.
- - Then the last item is the Fuel Injector Pump which may be out of timing if somebody fiddled with it. That is a major problem requiring diesel mechanic and more importantly the engine maintenance manual. Get the full model number of the engine and its year and you might find the manual either on the internet or in a dealership.
- - Next best would be to find somebody with the exact same make/model engine and take a photo of the injection pump and its alignment. Normally the pump has an index mark somewhere along the base where it is bolted to the engine block. Closely examine this area and find the index mark and then do the same with a "sister" engine.

[Bilgediver]

Originally Posted by 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.

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

would WD40 be better? or some ting else? (Then wait some days and try turning over agin?)

Questions /comments / suggestions welcomed

Any suggestions?

WD 40 is not really the correct thing...It is a dewatering fluid more than a proper lubricant...Try and get a good penetrating oil. her in the UK a product called " Plus Gas" is best.. Nothing to do with the fuel gas used in cars.

I have heard some folk save the day by pouring hot engine oil into the bores but do this with care.

[Scare_Rab]

engine now "turning over sweetly - but still not firing"

mechanic came down this arvo - bled fuel lines.

left.

will return tomorrow witha multi-meter - to test if glo plugs getting power

Ho Hum.


(Admin - moderator ... this thread began with "engine not turning over"

now moved to "All good - but will not start"

is there any way to alter the "heading / 1st post" = to relect this?

[Scare_Rab]

reading these forums I see...

"Caution All engines: If the engine does not start on the first attempt, turn off the raw water cock. When the engine starts, turn on the cock immediately. Prolonged cranking with the raw water turned on will fill the engine cylinders with water.

from : BLEEDING AIR

knowing that water will not compress, this sounds like the fast track to "broken bits"

until now I have kept the inlet seacock open.

is it too late?

ought I have it closed?
or - is this a YANMAR thing and not Kubota (or Perkins or ...)

[Jetexas]

I tried to revive an old Westerbeke in the same manner you're attempting to revive this Kubota. I got to the exact same point - it would turn over, just never actually start. I too bought another battery thinking it just needed more power. It was a mess.

I had already sunk $500+ into it before I gave up and opted to buy a Kubota replacement engine.

It can be two things at this point, compression or the fact that the starter just isn't spinning it fast enough.

You can get a remanufactured Kubota starter on eBay for under $100.

If that doesn't work, you're going to need a rebuild.

I THOUGHT my Westerbeke had good compression until I got my new motor. Turning the new motor over made an audible popping sound that definitely was not there in my old motor.

[DeepFrz]

Is there a drain valve on the muffler? If so drain all the water out or the muffler. Water will back up and fill the cylinders with water (if the raw water pump is working), and you are right, it can be the kiss of death.

[Stillraining]

Originally Posted by Scare_Rab

reading these forums I see...

"Caution All engines: If the engine does not start on the first attempt, turn off the raw water cock. When the engine starts, turn on the cock immediately. Prolonged cranking with the raw water turned on will fill the engine cylinders with water.

from : BLEEDING AIR

knowing that water will not compress, this sounds like the fast track to "broken bits"

until now I have kept the inlet seacock open.

is it too late?

ought I have it closed?
or - is this a YANMAR thing and not Kubota (or Perkins or ...)

Yes you should have closed it..

No its not to late.

A hydraulic lock is immediate...if it hasn't happened it hasn't happened.

I will be the first to apologize for not mentioning it...I keep forgetting about it..thinking people know about this issue...take solace in that its a possibility of happening not a guaranteed outcome....sorry

When she fires don't forget to reopen it though.

One thing about an engine with compression releases is that having them open while spinning the engine will give any fluid a place to go without damage...I highly doubt you have any damage to your engine.

Do you have white smoke comming from your exhaust while cranking...if so that is unburned diesel and she wants to fire something is just keeping her from it.

1) Could be low compression
a) Bent rod
b) valve adjustment
c) Worn cylinder wall and rings

2) Could be timing
a) Valve lash/ adjustment
b) Pump timing

3) Could be fuel delivery
a) Pump timing or bad pump
b) Injector atomization or proper function
c) air in lines

An engine that has proper everything but missing compression is the candidate for a little help with ether...all other should not need it.