Low Oil Pressure- Engine Seizing?

[polaraligned]

I get the tractor running for a few minutes, then it makes some god awful noises and stops....like it is being ground to a halt.
The oil gauge used to read a bit low, but now I see it does not read anything at all. I have heard other engines seize due to no oil, and this is a scary resemblance to that sound.
I don't know if the engine has ever been rebuilt. Would the best thing be to rebuild it?
and how much does that cost?
Does the engine have an oil pump similar to a v8 auto engine?


Thanks,
Scott

[Bill V in Md]

Scott,

I wonder if the slow turning engine problems you were having is related to this. If so, it doesn't sound promising. The oil pump is a gear type pump that is driven by the cam shaft. It is located at the rear of the engine. The first thing I would want to inspect is the crankshaft and bearings. An engine rebuild will likely run you in excess of $1,000 for parts and labor, and could be significantly more depending on what you find.

Good Luck

[ricky racer]

Sorry to hear about your situation. First, yes the Cub has an oil pump (gear pump) located behind the flywheel. Has the tractor set for a long time since it last ran? If so, it may have lost it's prime. You can prime the oil pump through an 1/8" NPT pipe plug on the rear of the engine block on the left side of the block, right near where the block attaches to the torque tube. However, from the sound you described, the harm may have already been done.

You may want to pull the oil pan off and pull the main and rod bearing caps off and inspect the bearings. If you have ruined the bearings, they need replaced and the crank may need to be ground to clean up the journals. Each cap is marked and must be replaced in the correct location and properly torqued when reassembled. If the bearings are shot, you don't want to run the engine and cause further damage.

The pistons could also be seized in the bores but that is probably less likely than the crank and rod bearings. Rebuilding the engine, if you can do most the work yourself will still run you about $1000 for parts and machine shop services.

Hope this helps you get started.

[John *.?-!.* cub owner]

The oil pump is a gear pump located behind the flywheel.and has a pickup tube that runs down into the oil with a screen over then end. I would start there. for the problem, but as has been mentioned, you have already down some damage.

[Olred]

does it sound like this?
http://s158.photobucket.com/albums/t109 ... GP0951.mp4
i did not properly prime my oil pump and locked up my motor, put in all new rod and main berings and a new conecting rod because i spun one...i wish you better luck then I

[White n Yella Fella]

Ouch! That video clip didn't sound good at all...expensive lesson, eh?

You guys got me wondering about a gear pump, now. I was always under the impression that if a gear pump (positive displacement) was not dry (having some oil residue) in the gears, that it would prime its self and pump.

Are my gears not meshing, here? Or is there something gravely different with a cubs gear oil pump? I don't question the frozen engine, just the failure of a positive displacement gear pump to pump, unless it is totally dry and not lubricated...


WnYF

[Steve Butram]

Could it be possible that the hydro pump is dead headed ?

[Bigdog]

The zero reading on the oil pressure gauge needs to be investigated and corrected but it is also possible that something as simple as the fanshaft may be locking up killing the engine before it has a chance to build enough oil pressure to read on the gauge. Try loosening the belts and turning the fan by hand. If it is OK then your problem is more serious. I would check this before tearing into the engine.

[polaraligned]

does it sound like this?
http://s158.photobucket.com/albums/t109 ... GP0951.mp4
i did not properly prime my oil pump and locked up my motor, put in all new rod and main berings and a new conecting rod because i spun one...i wish you better luck then I

I think that is it...

And that ruined all your bearings? ugg...Mine started up and ran several times and made that sound each time....
The Cub sat maybe 4 or 5 months before running it this time. It always had low oil pressure. I read that was pretty normal for an older engine as they were worn.

Can you get to all the bearings from underneath? or do you have to disassemble the whole tractor to get this engine rebuilt?

I paid $1800 for the tractor and it was supposed to have been thoroughly "gone thru". It was painted with a bunch of new parts on it. I guess that means nothing unless the engine was done. I get screwed again. I am better off not buying anything because I always end up on the short end of the stick.

Maybe I should prime the pump and try again...nothing to loose.
Can someone point me to directions on priming the pump?

Thanks guys.

[challenger]

I sense your frustration at present but I would advise against trying to run it again. Take the pan off and see what you have by way of connecting rod bearings. If it has seized up a time or two, the babbitt material may have been displaced on the bearing surfaces and may even be adhering to the crank. The next thing that happens is that the bearing inserts turn in the rod journals. Then you will need to replace the rods in addition to the bearings. If you find lower end damage, you may consider looking for a good used engine. Ralph has them from time to time, usually in the 200 - 300 dollar range.

[Eugene]

Do not start the engine. Check engine oil level.

Remove the hydraulic pump from the engine. Also check fan, fan belts, generator to see if they are free - not binding.

Remove the allen screw/plug on the left rear of the engine. Put a 1/2 cup of oil into the plug. Rotate the engine by hand 1/2 turn and put another 1/2 cup of oil into the plug. Rotate engine another half turn and put in another 1/2 cup oil.

If engine is free - start engine. Watch for oil pressure and listen for noise.

[Barnyard]

The Cub sat maybe 4 or 5 months before running it this time. It always had low oil pressure.

Did you prime the engine before starting after it had sat this long? If it lost it's prime it would show no oil pressure and lead to the problems you now have. Four or five months may not have been too long to sit but if it has no pressure at startup that is a good indication of needing primed, before it is too late. In this case it may be too late, but don't give up too soon.

Check for the things Bigdog and Eugene suggests. Hopefully it is minimal damage.

[ricky racer]

The zero reading on the oil pressure gauge needs to be investigated and corrected but it is also possible that something as simple as the fanshaft may be locking up killing the engine before it has a chance to build enough oil pressure to read on the gauge. Try loosening the belts and turning the fan by hand. If it is OK then your problem is more serious. I would check this before tearing into the engine.

Big Dog is correct in his approach. This problem happened recently to another member of this site. Maybe some one can find your a link to that posting.

Also, when a Cub has been setting a bit, the oil in the filter housing will drain down and it will take several seconds for the housing to fill back up with oil. It will not register any oil pressure until the housing is full.

[polaraligned]

I appreciate your time guys.
I will have to drop the pan (after checking nothing else is binding).
I just don't have the time at the moment to do an engine rebuild on this tractor.
I knew nothing about the need to prime the oil pump.

Scott

[Clark Thompson]

where do you get a rebuilt engine done properly for $1000.00?? Ill take 3 right now.