Need troubleshooting help Takeuchi TL140 Isuzu 4JG1T

[jimpad]

My skidsteer developed a knock which seemed to be coming from the front of the head, it also ran poorly and had low power. I adjusted the valves and didn't find much adjustment required but the knock seemed to go away although I was not able to put under load. Finally got to put under load and the knock came back. I thought sure it was a valve problem so I pulled the head and the valves appear fine, although I haven't disassembled the head. The only thing that seems odd is that the front cylinder has very little soot on the head wheras the other cylinders have a slight layer of soot across the head and valves, the difference is very noticeable. The machine runs good enough that I think it's a least running on 3 cylinders, so I suspect a problem with the front cylinder.

So now I'm thinking a fuel issue or maybe cam/lifter issue.

1. Does this line of thinking make sense?
2. Is a knocking consistent with a cylinder not firing?
3. Is a knocking consistent with a pump problem?
4. Does this engine have lifters... hydraulic/mechanical (pushrods look good)?
5. Is knocking consistent with cam/lifter problem?
6. Am I even on the right track?

 

[Delmer]

No. Pull the #1 injector and have it tested. Or pull them all and have them all tested, but LABEL them so you know which was where.

 

[jimpad]

That's my plan, but why does it make a knocking sound if it's a bad injector?

 

[thepumpguysc]

an injector will hammer an engine like its coming apart..
Do as Delmer says.

 

[Delmer]

Thanks for the expert second opinion.

My understanding is a bad injector will leak and allow enough fuel into the cylinder to detonate it early causing a knock and robbing the power from the other good cylinders.

Either that, or a spray pattern so bad that it detonates late with a an excess of fuel already in the cylinder, instead of burning smoothly at the same rate that it's injected.

 

[jimpad]

Man, that'll be great if it's just an injector. Wish I'd come here before pulling that head!

 

[Delmer]

If the shop says there's nothing wrong with your injector, then come back here before you put the head back on...

 

[jimpad]

Does anyone here know the Zexel part number for the injectors?

 

[thepumpguysc]

Don't replace them, get them checked.. even if you have to send them off.
The replacement cost is a lot more than getting them fixed..

 

[jimpad]

Should have them tested by Monday afternoon.

Pumpguy, I assume you're in the business? If repair is necessary, is this work something you'd be interested in? If so, is an injector repair a flat fee or per job?

 

[thepumpguysc]

Fuel shops charge a clean & test flat rate, then for parts..[gaskets and nozzle if required]
Are you getting a head set.. if so, it'll prob. come w/ gaskets for the injectors.. you should probably find out if it comes w/them.
Your looking for return line & bottom gaskets.

 

[jimpad]

Well I'm back. Had thepumpguy check them and he says there's some slight issues but shouldn't be enough to cause my problem. He's going to straighten them out and i was thinking to put it back together and see where I'm at. Any other suggestions before putting it back together?

 

[Delmer]

Only thing I'd do before putting it back together is measure the piston height in the cylinder, top and bottom of the stroke of all of the pistons. Also, try to do a "free play" test on the crankshaft with each piston half way down the power stroke, in turn. See how much the crank will turn without the piston moving. They should be all the same obviously.

Check the valves for sealing, sticking, broken springs. Use a liquid into the intake/exhaust port to check how fast they leak. At least peek at the valve and seat surface for wear.

 

[jimpad]

"free play" test is to determine bent rod, worn bearings? For the leak test, would spraying penetrating oil in ports and just looking at the valves for signs of dampness do it... is that what you mean?

I don't see worn bearings causing a lack of power though... am I thinking right?

 

[Delmer]

No, me neither. But let us know if you find anything...
Free play is bearing wear. Height is a bent rod, or bearing wear. Search the valve leakage testing, it's easier to see a pic of video.

 

[Michael Kast]

what ever became of this?

 

[jimpad]

Spun main bearing... complete rebuild

 

[Michael Kast]

Did you rebuild it yourself? and did you keep it?
I bought a 140 in October. It had been run hard and put up wet. I have been going over it and through it fixing a lot of little things, changed all fluids, cleaning and studying. I had no idea what I was getting into and currently feel very lucky. My biggest problem right now is a polluted fuel tank. I have been chipping away at it and tonight I moved a lot of heavy hard packed virgin clay soil for 2 hours without any power loss. I had a hairbrained idea and I think it may work. So far so good. It is certainly an improved machine. The hours meter was broken at 3300 hours. There is no telling how many hours since. Oil pressure at low idle is 35 pounds after running hard for a couple of hours. That is really all I can tell about the engine health. As the fuel issue resolves I will no more.

 

[jimpad]

Yes I did. Still have it and use it regularly on my farm. I've been following your progress... are you still getting that prefilter filled with junk?

 

[Michael Kast]

yes, until today. My hairbrain idea was to get a transfer pump with a big fuel filter and run both ends down into the tank. I asked a guy at NAPA I deal with a lot what he thought. I figured he was going to tell me I was going to kill myself but his eyes lit up. He said that should help and you may kill yourself but not doing that. I didnt have good fittings and one of the hoses started dripping after about 15 minutes so I put the filler tube back on the tank, gathered up my tools and started it up. I didn't expect any change but like I said, it was the first time I ran the machine where it didn't lose power and die from a clog. I love this thing! So when it needs a rebuild I will be rebuilding. Does yours have second gear? Do they all have the second gear?