Fingers crossed for you at this end. Would be great if it was something simple and inexpensive!
Steve
Steve
White smoke at high RPM
- Thread starter uler3161
- Start date
Orange2009
New member
Equipment
Kubota BX25, BH, FEL, 60" belly mower, 48" tiller, Middle buster, Stripe kit etc
Well picked it up today, started perfect, no smoke on idle, backed out of their shop, and let it sit outside and run for 3-4 minutes. When it warmed up I increased the throttle to full and the miss and small amount of smoke are still present. They are about 80% better, so I told the supervisor and he had the mechanic look at it, he swears its still just residual bad fuel. He said to run a couple of tanks of fuel and if its still there he will dig into the engine but he said there is nothing wrong mechanically. So bacically ill let it run today and tomorrow As well as try 2 different fuels and see what it does. Once I go through 2 tanks ill deliver it back to him if this still is the case.
It's been awhile, but I finally got around to doing some more testing on my b6000. Here's what I tried.
Bought a HF diesel compression tester. Thought I was supposed to turn the engine over about 10 times, but I had to turn it over about 20. One cylinder was a hair under 400 and the other was a hair over, so I'm guessing my compression is good. Should I have had to turn it over that many times?
Thought maybe the injectors were bad. I took them out and apart and I didn't see anything, but I'm not sure whether I'd know what I was looking at.
With the tractor running in the higher rpm range where the smoke happens, I cracked the fuel lines to each injector and both of them caused the engine to run poorer.
I thought maybe the compression release was engaging at high rpm, so I removed it and plugged the holes since I don't use it anyway. Didn't seem to help.
Coolant level doesn't seem to go down.
The tractor doesn't have near the power it did, but I think that's because I can't run it much over 1/2 throttle without it smoking. It seems to smell pretty strongly of diesel.
So I'm about out of ideas. Maybe there's something wrong with an injector and I just can't see it?
Bought a HF diesel compression tester. Thought I was supposed to turn the engine over about 10 times, but I had to turn it over about 20. One cylinder was a hair under 400 and the other was a hair over, so I'm guessing my compression is good. Should I have had to turn it over that many times?
Thought maybe the injectors were bad. I took them out and apart and I didn't see anything, but I'm not sure whether I'd know what I was looking at.
With the tractor running in the higher rpm range where the smoke happens, I cracked the fuel lines to each injector and both of them caused the engine to run poorer.
I thought maybe the compression release was engaging at high rpm, so I removed it and plugged the holes since I don't use it anyway. Didn't seem to help.
Coolant level doesn't seem to go down.
The tractor doesn't have near the power it did, but I think that's because I can't run it much over 1/2 throttle without it smoking. It seems to smell pretty strongly of diesel.
So I'm about out of ideas. Maybe there's something wrong with an injector and I just can't see it?
Compression is fine. Also means head gasket is fine.
Consider pulling injectors and hooking them up to the injection lines so they spray into the air. DO NOT LET THE SPRAY CONTACT YOUR SKIN OR HANDS!!!
While cranking the engine over, you are looking for a good spray pattern. No streams or "ropy" spray... Also no leaks before they pop and spray.
I'm *guessing* that we have a faulty injector. I would recommend sending both of them to a injection shop for testing/rebuilding. Hopefully that will solve the problem once and for all.
Good luck,
Steve
Consider pulling injectors and hooking them up to the injection lines so they spray into the air. DO NOT LET THE SPRAY CONTACT YOUR SKIN OR HANDS!!!
While cranking the engine over, you are looking for a good spray pattern. No streams or "ropy" spray... Also no leaks before they pop and spray.
I'm *guessing* that we have a faulty injector. I would recommend sending both of them to a injection shop for testing/rebuilding. Hopefully that will solve the problem once and for all.
Good luck,
Steve
I am not sure the spray pattern is bad, so I took a video
http://www.youtube.com/watch?v=-TOrr-gjXEY&feature=youtu.be
Any thoughts?
http://www.youtube.com/watch?v=-TOrr-gjXEY&feature=youtu.be
Any thoughts?
It is hard to tell from the video. Having a shop test them will tell you a lot- either they are your problem, or they aren't. I would want someone well versed in injectors to test them- bad injectors can wreck your pistons. It isn't worth the little bit of money it takes to get them properly tested.
Thanks. I was worried the video didn't show it very well. It looked to me like the fuel came out about an inch or so before it started to fan out. I'm not sure if that's what it should be doing. Both injectors seemed to have the same pattern. I guess I'll try to find someone that can test them for me.
Any large truck repair shop should be able to either test them, or tell you who can test them in your area.
I've never used these guys, but have seen some references online that were positive. They are probably only a day or two away by mail.
http://oregonfuelinjection.com/
Looking at your video I would say your spray pattern is poor. More like a stream. Poor injectors will toast an engine is short order. Chances are you have scored cylinders already, and maybe even eroded pistons. Get the injectors serviced and try it.
They also look like they leak after the initial pulse which would give you the whitish smoke.
They also look like they leak after the initial pulse which would give you the whitish smoke.
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Same symptoms on my B8200, white smoke on start up, slight miss, etc. etc. past couple of times the engine hydro locked then fired, noticed that the smoke had changed from white to steam. Pulled head knowing that at least the head gasket was bad. Found that the head is cracked between the valves on the center cylinder.
The white smoke and miss on mine was from the coolant getting into the cylinder, that cylinder would not fire right away due to the coolant, the unburnt fuel would show as white smoke and than after the engine was running for a moment the missing cylinder would fire and the smoke would clear, mostly.
Head is at local machine shop who has been doing Kubota heads (among others) for years, he said that if the engine was overheated at some point they are notorious for cracking. I can't argue with him as the crack is plain to see if you look close.
My money is on you having at least a bad head gasket. I do not at all believe that you have injector issues, nor do I think that you have a bent rod, though if you do have a bad gasket and it gets worse you could bend one if you don't get it fixed and it starts to hydro lock on it's own (without your mis-hap)
The only way to know is to open her up.
Dan
The white smoke and miss on mine was from the coolant getting into the cylinder, that cylinder would not fire right away due to the coolant, the unburnt fuel would show as white smoke and than after the engine was running for a moment the missing cylinder would fire and the smoke would clear, mostly.
Head is at local machine shop who has been doing Kubota heads (among others) for years, he said that if the engine was overheated at some point they are notorious for cracking. I can't argue with him as the crack is plain to see if you look close.
My money is on you having at least a bad head gasket. I do not at all believe that you have injector issues, nor do I think that you have a bent rod, though if you do have a bad gasket and it gets worse you could bend one if you don't get it fixed and it starts to hydro lock on it's own (without your mis-hap)
The only way to know is to open her up.
Dan
Since you say it's been hydro-locked, It very well could have a bent rod. Before you turn any wrenches get a thermal gun and take a reading on each exhaust port. They should be close in temperature. Since it's smoking, one of them will be lower than the other and the one with the lower temperature is the one causing the issue. A compression test will also rule out a bent rod and if all of the cylinders are somewhat equal then start looking at injectors.
North Idaho Wolfman
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