Knockin' and A-smokin'

[CaveCreekRay]

OK Guys,

A dear friend who got me into the world of Orange is having a weird problem even the dealer cannot solve...

He has a L3410 with 1451 hrs on it and it has been to the dealer for regular service. He can't remember when he bought the tractor (1993?) and the data plate is illegible.

Lately, the engine starts knocking and the exhaust starts smoking when the engine is under moderate load. Sounds like pre-ignition to me but I am not a diesel guy. He has two large horse pastures that he drags weekly for weed control so the motor gets up to temp and stays there for a couple hours dragging a box scraper. No problems there. When he tries to drag the box on a slope, he gets the "knocking" and smoking.

It just started doing this about five hours ago and the dealer looked it over and cannot find anything obviously wrong. There is a nice soot pattern forming on the side of the hood. The dealer just installed new rear tires that appear to be a tad oversize in diameter. I am thinking they raise his lower range due to the increased circumference and that might be loading down his machine. The knocking occurs now even in the lowest range gearing.

Any ideas? Need new glow plugs? A clean-out of the cylinders? (Do they make a water injection system for diesels like they do for cars for this purpose?)

I told him I would post this on the forum and somebody would have experienced it or would figure it out.

Ray

 

[bh115577]

Just had one, different model but still Kubota, in my shop with similar symptoms and it turned out someone put gas in the diesel. Remove the cap and give it the sniff test.

 

[CaveCreekRay]

Anyone have experience with over-size rear tires? The new ones barely clear the fenders and there must be some effect on the drive train.

I am not sure how many hp the L3410 has but with a few more inches of moment arm, this has to reduce torque available. Of course, for highway driving, you get an overdrive effect that allows you to sip gas at 12mph.

 

[Orange Turbo]

injector?
Wile it's running, start cracking the injectors loose, one at a time, like your bleeding them and see if the knocking quits.

 

[Grouse Feathers]

The torque the engine transmits to the rear wheels remains the same. The force the wheels have available to transmit to the ground is reduced (the same towing force available at the draw bar) because the lever arm is longer. The difference in tire radius times divided by the original tire radius gives you the ratio to determine the lost force (multiply by 100 to get the percentage loss). If the original radius was 24" and the new radius is 26" the ratio is .083 and the percentage of towing force lost is 8.3%. Depending on conditions the bigger tires may give more traction. So for some conditions bigger tires may provide more available force. I don't think any of this should affect the Knockin' and A-smokin', use a lower gear.

 

[kuboman]

Fuel filter? Bad fuel?
No the tires will not give those symptoms.

 

[Tallahassee Kubota Man]

Anyone have experience with over-size rear tires? The new ones barely clear the fenders and there must be some effect on the drive train.

I am not sure how many hp the L3410 has but with a few more inches of moment arm, this has to reduce torque available. Of course, for highway driving, you get an overdrive effect that allows you to sip gas at 12mph.

Ray, I've got a 2001 L3010 which is the same tractor with the exception of the engine. I bought it with the R-4's. They look too big on the back, very wide and only an inch or so clearance with the fender. I may have missed it, but what type tire is on yours?

 

[ShaunRH]

Knock can also be valve adjustment.

But always check fuel first. Odd that it does it on slope with the same implement. I'd say there's a fuel issue there, maybe blockage or a pump problem.

 

[Porkman]

Alway suspect diesel fuel first but...what color is the smoke? White or black? Sounds like an injector is pissin' instead of spraying. Before I spent big bucks, if it were mine, I'd drain the fuel and refill with fresh with Amsoil Diesel Injector Clean in it. I've seen that stuff remove deposits that other wouldn't touch.

 

[CaveCreekRay]

Thanks guys!!!

GF-

The reason I ask is I had over-size snow tires on my Opel in college and I ended up shifting into third a lot because the monster 1100 cc motor couldn't handle slight hills that it could negotiate with ease with summer shoes on.

TKM-

Yup... that is what his tires look like. About an inch clearance on the fenders right now.

PM-

The smoke is black. Water temp is fine with clean oil.

Will try new fuel with some injector cleaner and see how that goes.

 

[Tooljunkie]

Check oil levels? Like engine oil too high and hydraulic low?
Slope should not affect performance, unless water is involved.
Doesent explain the smoke. Check air filter, maybe clogged.

 

[Porkman]

The smoke is black.

I'm thinking you have an injector either leaking or streaming instead of spraying. Try the fresh fuel with cleaner. If no luck then ,as long as it is not a direct injection fuel system, you can crack the injector lines open one at a time as you listen to the engine. You might be able to narrow down which one(s) it is that way. Let us know.

 

[CaveCreekRay]

The only problem is the engine has to be under load to knock. That precludes "fiddling" with the engine underway. We'll report back on the results of a bottle of Stanadyne Injector Cleaner. The dealer also recommended a bottle of rubbing alcohol to grab any water. Dinna know that worked in diesels too.

Howie is going to run out the current tank of fuel on the flat lands of his property pulling his box scraper and then fuel it up with fresh fuel. We'll treat it and at the rate he burns through diesel, we should know in a week or so. He drags three acres weekly.

Thanks for all the ideas guys!

Anyone know what horsepower the L3410 pulls?

Ray

 

[Tallahassee Kubota Man]

Ray, Tractor Data has it listed gross hp at 35.1. I was thinking it was a little under 34. Guess it depends on where you get the info from.

 

[Adman1100]

The only problem is the engine has to be under load to knock. That precludes "fiddling" with the engine underway. We'll report back on the results of a bottle of Stanadyne Injector Cleaner. The dealer also recommended a bottle of rubbing alcohol to grab any water. Dinna know that worked in diesels too.

Howie is going to run out the current tank of fuel on the flat lands of his property pulling his box scraper and then fuel it up with fresh fuel. We'll treat it and at the rate he burns through diesel, we should know in a week or so. He drags three acres weekly.

Thanks for all the ideas guys!

Anyone know what horsepower the L3410 pulls?

Ray

One more time. Air Filter???

 

[CaveCreekRay]

TKM,

Thanks!

Adman,

It checked out fine but I'll suggest Howie pick up a new one just to be sure. Can't run efficiently if it can't breathe. (Just like us!)

Ray

 

[BAP]

If the tractor has a rubber hose running from the air cleaner to the intake, check that out. I had a Case 580K backhoe that did similar symptoms and we chased the cause for a long time. Had the dealer look at it and they had the injectors rebuilt, injector pump rebuilt and so on and could not find the cause. Finally we had a long time John Deere mechanic look at it, and he found out that under load, the hose connecting the air cleaner to the intake was collapsing internally blocking off air flow. At an idle it was fine, but under load, the rubber had aged and softened enough that it would collapse.

 

[CaveCreekRay]

BAP,

Great story... we'll look for sure!

Ray

 

[Tooljunkie]

Knew a guy that spent a lot of money trying to make his 6.2 chevy quit burning oil. Was air filter, cost a couple thousand.

 

[CaveCreekRay]

I always wondered about Kubota allowing users to "wash out" their filters. I know the filter media is probably like a cotton material that allows it but...

Tapping off as much dust as possible and then blowing it off with a compressor is, to me at least, the best way of getting those little tiny "rocks" out of the filter media. Washing the filter only solidifies much of the microscopic material, like adding water to concrete dust.

I had to wash my filter out when I got my unserviced machine and I used a drop of dish soap the second wash because the first wash didn't seem to release much of the grit. The soap really helped get the filter clean. I use the dual filters now as extra precaution.

Think about it: Your filter is only passing half the air it should. You are fine running at 50% load as the air passing the filter allows an acceptable mixture for the fuel supplied by the fuel control.

Now, really max perform the machine. When the fuel control pours more go-juice into the cylinder, the air cleaner is still only passing half of what the engine needs. Suddenly, your mixture goes sky high rich and without enough air to complete combustion, your engine starts passing unburnt fuel in the form of soot. Yuk!

Stay tuned...