D21- Clicking, smoking, skipping- intermittently

[mitch504]

Komatsu D21-6, changed waterpump, ran it hard for a few days cutting fireline in the marsh. It ran perfectly, temp gauge stayed in the lower half of normal, lost no water, sounded great. Brought it home and left it on the trailer for about a week. I needed the truck for something else, so I checked the fluids and started it. As soon as it started, it started clicking, almost like a lifter tapping, skipping, and blowing a thin blue-gray smoke. I ignored the smoke, (because I had just started it), until I realized it came and went with the other symptoms. When I raised the rpms a little, it stopped, then came back. I ran it about 5 minutes or so, and it came and went, not necessarily changing with throttle position.

It is a four-cylinder Komatsu diesel with glow plugs and an inline Zexel pump.

I unloaded it and haven't had time to look at it since. When I get back to it, I'll do all the normal stuff, like cracking lines and shooting it with a temp gun, but I just wondered if this rang any bells for you guys.

 

[Vetech63]

Sounds like it could be an injector to me. Replace the fuel filters to make sure you haven't picked up water in the system. Crack your injector lines to see which cylinder is acting up. remove the injector and see if the tip is carbon fouled or damaged.

 

[thepumpguysc]

If you were in the marsh, it might be something stupid like a stick caught somewhere??
Don't break-out the wrenches just yet.. lol
You know how to diagnose all the other stuff..
but then again, you did just change the h2o pump.. any chance a bolt came loose & clicking against the fan blade?
OR a blade "walking"??

 

[mitch504]

the click, smoke, and skip goes together exactly. when one stops, they all stop. when it does one, it does them all

 

[darinray]

Did you get this resolved... I JUST seen this and wondering if you checked the banjo fitting on the lift pump ( primer pump that you unscrew to prime)? Take the fitting off the bottom of the pump and check the screen that is inside the fitting.. pinch off the fuel lines so you don't drain the tank. Good luck..

 

[mitch504]

Guys, you don't know how it pains me to write this, but, here goes (I hate when people don't reply to their own threads to let us know the answer):

I finally fixed the D21 today. I hadn't been within 50 feet of it since the day I started this thread, but today I needed it bad. I needed to drag 500 lbs of steel in mud way too bad to use my pickup, so I went to get my 215c and found somebody had stolen one (?) of my brand new batteries out of it. (why not both?, not that I'm complaining.)

I went to the dozer and checked the oil and water again, they were both fine. I started it, but it took way more cranking and glow plug time than usual. It ran rougher than before, still with skipping, smoking, and clicking perfectly together. The click was more like a hard tap now. When one would stop, they all would stop, and it would run smooth. I put it in gear, and as soon as the tracks tightened up, it would die. It would restart immediately.

I had a thought, and pulled the fuel tank dipstick. AHA, just about an inch in the tank! I dumped in a few gallons and restarted it. Within about a minute, it smoothed out and ran smooth! I worked it for about 10 minutes and she ran great! I spent the next 30 minutes trying to get my foot up high enough to kick myself in the a$$.

 

[Ronsii]

LOL, Well at least it was a simple fix those are the best kind.



And now that it has been that low it probably wouldn't hurt to check any screens and stuff like that.

 

[thepumpguysc]

Dam, Mitch.. Glad it was sumpin simple.. but DAM.. Lol
Ronsil has a good idea.. as long as the fuel is that low.. check the screens & CHANGE the filters.

 

[DPete]

At least you didn't call out a mechanic LOL

 

[Ronsii]

^^ or take it to Ziegler... sorry, couldn't help myself