Need help identifying oil leak

[C4pt4inMatt]

I've been working on bringing back to life an old L1500 and I finally got it running but noticed it's spitting oil out of what seems like an overflow or something. It seems to be a decent amount coming out as the motor runs. What is this pipe and I'm guessing something isn't right so what should I be looking to fix?

I'm still learning about this thing, and diesel engines in general to be honest so any help is greatly appreciated. I've attached a pic of where the oil is coming from.

 

[Dave_eng]

A much wider angle photo would help in locating where on the side of the engine this is happening

Dave

 

[C4pt4inMatt]

A much wider angle photo would help in locating where on the side of the engine this is happening

Dave

Sure thing, see the attached pic. It's on the rear of the fuel pump kind of next to the hydraulic pump.

 

[Dave_eng]

Do you realize tyour L1500 is a Gray market tractor and American Kubota dealers will not get involved.

Looking at the L175 parts illustration the pipe in question appears to be a breather pipe for the fuel injection pump and should have a length of hose attached so any leakage drains unto the ground.

Dave

 

[C4pt4inMatt]

Yea I understand it's a gray market and for the most part I've been able to find what I've needed. I figured it was some sort of breather but I was alarmed by how much oil is coming out of there. Looking at that diagram you posted, is there maybe a diaphragm or something that would help retain some of the oil? Or is that much oil coming out an indicator that something is off time or worn out?

 

[Dave_eng]

From looking further at the parts info, there seems to be some sort of media inside the housing.

The media etc may serve to block raw oil from exiting the housing.

Why is their apparent diesel fuel on top of the injection pump?

Dave

 

[C4pt4inMatt]

From looking further at the parts info, there seems to be some sort of media inside the housing.

The media etc may serve to block raw oil from exiting the housing.

Why is their apparent diesel fuel on top of the injection pump?

Dave

I'll pull that breather assembly today and see what it looks like inside.

The diesel on top is from me bleeding the lines just prior.

 

[Russell King]

I know on my L185 there is a similar vent on the valve cover. The media there is something like a Brillo pad.
If you take your vent off you can probably see what happens if you run the tractor for a little while. There should be some oil mist there or some oil spray but I assume the vent would be placed well above any oil level.

On mine it is the highest point on the engine but still has some oil dripping out due to blow by.

The Kubota tube is nothing special on mine, it just fits tight onto the vent and in a support or two. The material used is fairly stiff and hardens with age and contact with oil.

 

[C4pt4inMatt]

@Russell King this breather that @Dave_eng mentioned is indeed similar to what you mentioned having on your L185. I pulled the breather off this morning and inside is a piece of perforated steel, then a stainless brillo like media, then another perforated steel. Nothing was plugged or torn so I just reassembled.

I'm starting to think that I have some worn rings allowing a lot of blow-by. For one it's been super hard to start with a considerable amount of smoke coming out of the exhaust and a decent amount through this breather, all when just cranking. This is weird because over a year ago before I started overhauling this thing I started it and really didn't have much trouble getting it going. The only difference then vs now is I was feeding it 100% Diesel Purge because I didn't know the status of the other fuel delivery components at the time. Now that I am feeding it fresh diesel, I can't get it going very easily. I've tested the glow plugs and they seem to be good. I've checked the timing and the fuel pulses seem to be in time with the marks on the flywheel. I also checked the valve clearance it most were close, one was off slightly so brought it into spec (0.20mm).

At this point I guess I need to do a leakdown test. I did get it going at one point but I had to feather the throttle to keep it going. If held in one spot it would start to die and I'd rev it up but it would seem to rev wildly high so I'd bring it back down some but then it would want to die again so gave it more throttle again. I kept it running for a few minutes like this.

 

[Pau7220]

At this point I guess I need to do a leakdown test.

I don't think a leakdown test will give you the info you need. A simple compression test will. Pressure has to be up there to ignite that fuel.

Any chance the oil level is overfull?

 

[C4pt4inMatt]

Oil level is good but unfortunately compression test is not. I only have 200psi on #2 and 300psi on #1. I added some oil to #2 cylinder to see if the rings were the culprit and was only able to get it to 300psi max. I believe the intake valves are to blame as there's a good amount of soot/carbon throughout the intake manifold.

With that I pulled the head and pistons to inspect everything. There isn't much scoring but there is a decent ridge around the too of the cylinders. I've honed them out but now the piston to cylinder clearance is too large so I'm looking at either resleeving it or continuing to bore it out for oversized pistons. Trying to decide.