Low Oil Pressure

Arby · Apr 25, 2001

I bought a used L295DT last year and have been very pleased in rugged use. However, recently the low pressure light came on and
has remained on. I don't know what oil the previous owner used, and I used a Penzoil of appropriate weight and design. I suspected that the oil change may have accumulated sludge in the filter or the regulating valves, but no... I replaced the filter and cleaned the valves. I determined that the pressure at the sensor could be held with my finger over the hole. I tried un-screwing the filter with the engine running and forced the filter seal which would seem to tell me that there is pressure at least to, if not through, the filter. Anyone have a similar experience and better yet a solution?

Anonymous Poster · Apr 25, 2001

Arby,

I don't have any specific answers for you, ...just an observation about the "finger over the hole". I've been told in the past (accurately?) that very little oil-pressure is actually needed for adequate lubrication under normal relatively-low-speed (rpm) operation, ..anywhere from 7psi up, or so.

If this is so, then the amount of lbs. of pressure exerted through the considerably-less-than a "square inch" opening in an oil line or port could indeed "be held" by a finger, ...which would NOT mean that oil pressure wasn't "adequate".

Don't know how true this is, ...just passing it along.

Will be interesting to see other comments.

Larry

skent · Apr 26, 2001

Arby,

Did you change the filter?
If you were to remove the filter now, does it have oil in it?
Does the Oil light stay on with a cold Engine (thick oil)?
Try screwing a Pressure gauge (not very expensive) in place of the pressure sensor. Do you have over 10PSI? Does it go up with RPM?
A friend of mine with a Yanmar had a similar problem. He had no (or very little) oil flow. We found the oil pump (located on the front of the Engine block under the timing gear cover) had 'split' up the middle.
Keep us posted on your progress and good luck.

Steve
"Amateurs built the Ark. . . . . . . .Professionals built the Titanic"

Arby · Apr 26, 2001

This is getting very interesting.. The oil pressure light is on even cold. The replaced oil filter has oil as well has significant pressure, enough to distort the gasket if I spin th filter out enough to leak. I've used an inexpensive oil pressure gage, but the pressure isn't sufficient to register. When I said in my first postinng that I could hold back the oil with my finger, I meant to say with very little pressure on my part. I just hope that there's enough pressure to get up to the rocker arms. I suspect tht the pump is good, otherwise nothing would be fed, including the filter. I sure appreciate the insights! I hope I don't have to tear this down.

Anonymous Poster · Apr 26, 2001

The first thing you need to do is get a reliable pressure reading. If your reading low to no pressure the most likely cause: There is an aluminum plug in the end of your camshaft that has a nasty habit of blowing out. It's there to close off the oil gallery in the cam after drilling at the factory. This is a very common problem on the older kubotas. The front gearcase will have to be removed to verify, if it turns out to be the oil pump that's in there too. You said you have pressure at the filter "when loosened" you will have flow if the oil pump's working, the cam gallery is further down the line so with this limited information I'm going to bet on the blown plug. But please get a good pressure reading before you tear into it. Could end up being just a bad sender or the sender lead grounding out somewhere. There's a bulletin for this problem, replacing the aluminum plug with a steel plug and tack welding it in, but the "right way' to do that is to remove the cam, do to grounding issues, which means the head has to come off which starts to turn the lid on that can of worms most are pretty familiar with. You can also get a new/original aluminum plug and take your chances with that one staying in
as long as the last one did/or not. Good luck........

Arby · May 18, 2001

Bingo!
It took me several days to get the time to get into the gearcase. sure enough, it was that plug in the cam shaft end.My dealer doesn't have an identifying part number for the plug, so I'm figuring out how to permanently repair it by some other means. Now I'm waiting for the case cover gasket from Japan to complete the reinstall. Thanks for your help. I wouldn't have known to look for something so small, especially since it doesn't look like a defect with the machining.

Thanks,
Arby

skent · May 18, 2001

Great Going Kubmech.

Great having your database available!

Steve

Anonymous Poster · May 18, 2001

My dealer does have an identifying part number. i'll get back to you.

Anonymous Poster · May 19, 2001

original aluminum plug part number, ref. L295 parts book, (camshaft page upper right corner) 15221-33630 changes to 15221-3363-0

steel (weld in plug) ref. service bulletin SB 79-7
part number 15401-33631 changes to 15401-3363-0

Note, both part numbers are still available.