L35 White Smoke

[chasex2]

Recently purchased a non-running L35 (953 hours) from an older man. Needed a lot of TLC and maintenance to get running. It is now starting and running reliably, but about 30 seconds after starting, significant white smoke (smells like diesel fuel) blows out exhaust. Possibly sounded like fuel knock, May just be the sound of an older diesel.

We thought stuck injector. Had injectors tested. 1 bad spray pattern, 2 were dribblers. Got new injectors installed. Same white smoke. When bleeding air out, cracked the fuel line at the injector 1 at a time. Cylinder 1 and 3 would cause engine to start to die when fuel line cracked. Cylinder 2 injector line can be completely cracked, no impact on how it runs. Bad compression?

Waiting for compression tester to come in the mail. Changed oil, it had no significant metal shavings, only glimmer of sparkle if in direct sunlight.

One anomaly is that the air bleeder screw seems to have no impact on runability. Fully open or closed, the tractor runs the same. No fuel ever comes out the bleed screw. Is this normal? Should the tractor run the same with the bleed screw open or closed?

 

[PoTreeBoy]

Recently purchased a non-running L35 (953 hours) from an older man. Needed a lot of TLC and maintenance to get running. It is now starting and running reliably, but about 30 seconds after starting, significant white smoke (smells like diesel fuel) blows out exhaust. Possibly sounded like fuel knock, May just be the sound of an older diesel.

We thought stuck injector. Had injectors tested. 1 bad spray pattern, 2 were dribblers. Got new injectors installed. Same white smoke. When bleeding air out, cracked the fuel line at the injector 1 at a time. Cylinder 1 and 3 would cause engine to start to die when fuel line cracked. Cylinder 2 injector line can be completely cracked, no impact on how it runs. Bad compression?

Waiting for compression tester to come in the mail. Changed oil, it had no significant metal shavings, only glimmer of sparkle if in direct sunlight.

One anomaly is that the air bleeder screw seems to have no impact on runability. Fully open or closed, the tractor runs the same. No fuel ever comes out the bleed screw. Is this normal? Should the tractor run the same with the bleed screw open or closed?

Welcome to OTT. There are several of us L35 owners on here and some very knowledgeable folks.

I can't help much with your white smoke issue, but you're probably on the right track with a compression check. The experts will want to know where the replacement injectors came from.

Yes, the engine will run just fine, normally, with the jet valve open. If the tank was low, the filter partially plugged, and you needed full power, maybe not.

You should not see fuel come out of the screw, it is a vent and a hose routes any air or fuel that bleeds out back to the tank. The diagram below is similar to the L35, there should be short hoses running from the jet valve to point A, A to B, B to C, and C to the fuel tank.

 

[KubotaCool]

Another thing is that it may be a timing issue, if the spoke clears up when warm this could be the issue if the compression comes back as good this could be worthy of a check.

 

[#40Fan]

White smoke is unburnt fuel. Running a compression test is a good first move.

 

[North Idaho Wolfman]

Yep dead cylinder

 

[Nicksacco]

Hi @chasex2
Compression testing is a good thing. Let us know what you find
Stuck or
/broken valve operation is a possibility too.
You might try swapping an injector too.

You do have high pressure fuel coming to #2 is that correct?

 

[chasex2]

Thank you everyone for the comments. Cylinder 2 is dead. All signs showed it was making no compression, and that the piston was not moving. So we pulled the head. Turned the engine over and cylinder two piston does not move. Threw a rod!

Now our question is, can we access the rod and rod bearing from the pan? Or does this engine require you to split the tractor? Suggestions are warmly welcomed.

Edit: there is a D1703 out of a generator for sale near us. 1300 hours. Ran when stored. Asking $750. Label says constant speed only. Could we swap cams from our current engine?

 

[North Idaho Wolfman]

Thank you everyone for the comments. Cylinder 2 is dead. All signs showed it was making no compression, and that the piston was not moving. So we pulled the head. Turned the engine over and cylinder two piston does not move. Threw a rod!

Now our question is, can we access the rod and rod bearing from the pan? Or does this engine require you to split the tractor? Suggestions are warmly welcomed.

Edit: there is a D1703 out of a generator for sale near us. 1300 hours. Ran when stored. Asking $750. Label says constant speed only. Could we swap cams from our current engine?

Yes you can pull the rod and piston from the pan, but if there is any damage to the crank that will require the engine to be pulled.

You would not need to pull the fuel cam, on that engine.
It's more than likely just the throttle control plate will be different.

 

[chasex2]

Thanks for all the help. Does anyone have suggestions for reputable and reliable aftermarket connecting rods, rod bearings, piston, and piston rings? Kubota prices are awfully steep compared to the aftermarket options. But are the aftermarket options high enough quality?

 

[North Idaho Wolfman]

Thanks for all the help. Does anyone have suggestions for reputable and reliable aftermarket connecting rods, rod bearings, piston, and piston rings? Kubota prices are awfully steep compared to the aftermarket options. But are the aftermarket options high enough quality?

I've done quite a few aftermarket sets and they all seem fairly consistent.
Not too bad of quality and fit.
One thing I don't like is the head gaskets, I tend to get OEM when i can.

 

[chasex2]

I've done quite a few aftermarket sets and they all seem fairly consistent.
Not too bad of quality and fit.
One thing I don't like is the head gaskets, I tend to get OEM when i can.

That’s reassuring. Do you have a preferred aftermarket website or brand?

 

[North Idaho Wolfman]

Rebuild parts from Kumar tend to be good, I've only had one issue and they replaced the parts quickly and without charge.

Kubota Overhaul Kit D1703 STD Parts

We are manufacturers and suppliers of kubota overhaul kit D1703 STD engine parts for sale, Kubota Parts Overhaul Kit D1703

www.kumarbrosusa.com

This is another I have used.

Overhaul Rebuild Kit for Kubota Engine D1703 D1703E

Overhaul Rebuild Kit for Kubota Engine D1703 D1703E

www.fridayparts.com