One interesting thing to note is that when I completed the compression test I removed both injectors and had the fuel turned off at the filter. I had the tester on one cylinder the other cylinder was open. When I cranked the engine a constant stream of mist was coming out of the open cylinder, is this normal. I assumed it to be diesel left over in the injection pump, but could that be coolant?
Kubota B5100 smoke
- Thread starter Smagner234
- Start date
Update
I took my injectors to Metro Fuel injection and they were able to test them on the spot. Turns out the injectors were both bad, one was barely spraying and the other was spitting in all directions. The gentlemen at the shop explained that I was not getting the fine mist that is suppose to emit from the injectors and instead they were spitting a large volume. This would lead to a lot of unburnt fuel in the motor. That is what was most likely spraying from my open cylinder (see post above) and that is also what is most likely causing the white smoke. The injectors are currently being rebuilt and I should have them installed this weekend. I will put in the Statadyne in and the issue should be resolved. I will have to say that the guys at metro fuel injection were awesome!! I would recommend them for sure. I am on the east coast but I think they have shops all over the country.
I'm not too excited about my compression but I think there is plenty of life in the motor. I will post the results this weekend.
I took my injectors to Metro Fuel injection and they were able to test them on the spot. Turns out the injectors were both bad, one was barely spraying and the other was spitting in all directions. The gentlemen at the shop explained that I was not getting the fine mist that is suppose to emit from the injectors and instead they were spitting a large volume. This would lead to a lot of unburnt fuel in the motor. That is what was most likely spraying from my open cylinder (see post above) and that is also what is most likely causing the white smoke. The injectors are currently being rebuilt and I should have them installed this weekend. I will put in the Statadyne in and the issue should be resolved. I will have to say that the guys at metro fuel injection were awesome!! I would recommend them for sure. I am on the east coast but I think they have shops all over the country.
I'm not too excited about my compression but I think there is plenty of life in the motor. I will post the results this weekend.
CountryBumkin
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Are you loosing coolant? The test would be to pressurize the cooling system (with radiator pressure tester tool) then wait to see if pressure on the tester's gauge drops, if so (and no external leaks) then crank the engine a few times and see if coolant comes out of injector hole.
But I expect that it is most likely a soaked cylinder from your bad injector.
From what I have seen, to date, I have never used any coolant, I will keep an eye on that though. I am thinking I am lucky I did not hydro lock the motor. There is a great deal of diesel in there. I also have some residual diesel under the valve cover, I'm thinking I should wipe that up before I put humpty dumpty back together again. I am looking forward to seeing how she runs with the new injectors.
CountryBumkin
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I would change the oil too, if you haven't already.
If you lay a rag over the cylinder injector holes and crank the engine enough, as you describe the amount of spray coming out, I would think there would enough liquid on the rag to tell if it is coolant or diesel (by smell).
If you lay a rag over the cylinder injector holes and crank the engine enough, as you describe the amount of spray coming out, I would think there would enough liquid on the rag to tell if it is coolant or diesel (by smell).
Update
I installed the rebuilt injectors and added the stanadyne fuel additive yesterday and after letting the engine idle for about 45 minutes the engine cleaned up and the smoke is 98% gone. The motor sounds a lot nicer now too. the gentleman at the injector shop did say that it's important to use a fuel additive on the old kubotas as the new formulation of diesel has a lot less sulfur in it which was used to lubricate the fuel pump. He also mentioned having a dramatic increase in rebuilds for old fuel pumps as a result of the reduced sulfur content in the diesel. Hopefully this info can help others overt a fuel pump failure.
Thanks again for the advice and help!!
Ohh and I torqued the injector housing to the head at 50ft/lbs. I had to really search for this spec as it wasn't in my workshop manual. Seems to have worked well.
I installed the rebuilt injectors and added the stanadyne fuel additive yesterday and after letting the engine idle for about 45 minutes the engine cleaned up and the smoke is 98% gone. The motor sounds a lot nicer now too. the gentleman at the injector shop did say that it's important to use a fuel additive on the old kubotas as the new formulation of diesel has a lot less sulfur in it which was used to lubricate the fuel pump. He also mentioned having a dramatic increase in rebuilds for old fuel pumps as a result of the reduced sulfur content in the diesel. Hopefully this info can help others overt a fuel pump failure.
Thanks again for the advice and help!!
Ohh and I torqued the injector housing to the head at 50ft/lbs. I had to really search for this spec as it wasn't in my workshop manual. Seems to have worked well.
Has anyone messed around with catalytic engine decarbonizer? Supposedly this helps clean up cylinder glaze and the rings etc. I found some on the internet but the company is in Australia. Has anyone used this and if so any sources in the us?
Also I pressure tested my coolant circuit and the system held the 12.8 psi, so the head gasket is in good shape.
Also I pressure tested my coolant circuit and the system held the 12.8 psi, so the head gasket is in good shape.
North Idaho Wolfman
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I wouldn't do any "treatments to it like that, it's a great way to end up with having to do a complete rebuild!
Kubota Diesel engines have very tight tolerances and small clearances, any material that could be added would either damage the injectors or other parts.
You say the head gasket checks out now, adding something could make that go away real fast!
Thank you, and your right. I should just leave well enough alone. The injectors and excessive valve lash appear to be the issue as the compression is OK and the head gasket is good too. I worked the tractor pretty hard this weekend and everything seemed to be A-OK. The little white smoke I have goes away after the tractor is warmed up. After all the engine is almost 40 years old..
Thanks again!
Thanks again!
Update
I had my injection pump rebuilt and I installed it today. The injector pump had a broken pin within it which was causing that cylinder to not properly fuel and also caused diesel to enter the crankcase. The engine now runs with zero smoke and it fired up without the glow plugs, which it wouldn't ever do before. The exhaust even smells better, I can tell I'm getting good combustion. The cylinder temperatures are now the same. The only thing I noticed is that the engine seems a bit load, I'm wondering if I may have taken to much lash out of the valves? The engine revs well and idles well it just sounds tingy (if that's a word). I have all of the same shims under the injection pump so I don't think that's it. I may post a you tube of it tomorrow, but any thoughts would be greatly appreciated. I will say that this has been a great experience to learn a great deal about diesel engines3.
I had my injection pump rebuilt and I installed it today. The injector pump had a broken pin within it which was causing that cylinder to not properly fuel and also caused diesel to enter the crankcase. The engine now runs with zero smoke and it fired up without the glow plugs, which it wouldn't ever do before. The exhaust even smells better, I can tell I'm getting good combustion. The cylinder temperatures are now the same. The only thing I noticed is that the engine seems a bit load, I'm wondering if I may have taken to much lash out of the valves? The engine revs well and idles well it just sounds tingy (if that's a word). I have all of the same shims under the injection pump so I don't think that's it. I may post a you tube of it tomorrow, but any thoughts would be greatly appreciated. I will say that this has been a great experience to learn a great deal about diesel engines3.
North Idaho Wolfman
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A tight valve will make them sound a little clattery ( ), also they are kind of tinny and clanky when they are running right.
), also they are kind of tinny and clanky when they are running right. Thanks haha I know I don't think I have ever heard my tractor run correctly. I was doing a bit of research on this site and I saw one of your recent posts regarding the install of a fuel injection pump in a Z500 engine (B5100). You had mentioned the use of gasket sealant and its potential to mess up the timing of the fuel pump. The thought occurred to me that might be my problem as I did use sealant, as the manual suggests, and I tried to put on a thin coat on the three shims and block surface. I used a aviation "this surface" form-a-gasket from Napa. Could that be the issue? I have the sound of the engine on the following YouTube link; "trim 088005B7 BCDC 4DDA 88A6 77BC124029FB". If you put that in the search browser on YouTube it will pick up the movie. I figured a trained ear would know if that noise was a timing issue. Also I did verify the valve lash and that is good, everything measures .0075". I had also posted a video of the engine, pre-rebuilt injection pump earlier in this string, for comparison. I don't think that sounds good now and my gut is telling me I will do some serious damage to the engine if I let it run like this.. haha
I would certainly welcome your thoughts.
https://www.youtube.com/watch?v=5qe7PtkK7RE
I would certainly welcome your thoughts.
https://www.youtube.com/watch?v=5qe7PtkK7RE
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North Idaho Wolfman
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Yes it does sound like it's off a little.
I would pull the pump, clean all the shims and surfaces and only use a very light coat of paint on the shims to seal them.
I would pull the pump, clean all the shims and surfaces and only use a very light coat of paint on the shims to seal them.
I tore the engine down and cleaned all the shims and mating surfaces, there was a bit of gunk in there and I could see from the patterning on the shims I wasn't getting even compression. So I decided to make sure they were good and snug, I set my torque wrench to 45 lbs which as it turns out was to much. I broke off one of the bolts and stripped the nut on one of the studs... Needless to say I have concluded the destruction of my engine for the evening. Ughh this is not good. My only hope is that I can extract the broken bolt with an easy out but the striped nut and subsequent stud will be a bit more challenging.
Be careful with those Easy outs, snap one of those suckers off and it's not so easy getting them out. I've been there once and could only drill it out with a hamper drill because of the hardened steel of the Ez out. A regular drill bit would walk off the EZ and move towards the softer metal. I would suggest drilling and tapping it out. Vice grips on the stripped bolt should do the trick if it's possible to get them in there. Don't get discouraged, if there is a will there's always a way.
My preference for extracting broken off hardware is to weld a nut or washer onto what's left. I hate easy outs.
If you have some straight flute extractor like this, they work real good.
http://www.ebay.com/itm/Irwin-53606...799198?hash=item25be146b5e:g:VjwAAOSwT4lWSWKI
Or might try a left handed drill bit.
Just be double extra sure to keep things clean around that mounting area! Cut a piece of heavy cardboard to fit down in the opening for the IP, so it fits real snug. Then smear grease on the cardboard and it's edges to catch any crumbs. Screw a screw into the cardboard to pull it out, but pick up anything you can with a magnet first.
If you have a wire welder you can do as MagKarl suggested.
You might also take a small chisel and try to turn what's left to see if it will un-thread. Sometimes you just get lucky and it turns real easy.
http://www.ebay.com/itm/Irwin-53606...799198?hash=item25be146b5e:g:VjwAAOSwT4lWSWKI
Or might try a left handed drill bit.
Just be double extra sure to keep things clean around that mounting area! Cut a piece of heavy cardboard to fit down in the opening for the IP, so it fits real snug. Then smear grease on the cardboard and it's edges to catch any crumbs. Screw a screw into the cardboard to pull it out, but pick up anything you can with a magnet first.
If you have a wire welder you can do as MagKarl suggested.
You might also take a small chisel and try to turn what's left to see if it will un-thread. Sometimes you just get lucky and it turns real easy.
North Idaho Wolfman
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D2Cat gives some excellent advice, I do as he stated or with a grease covered rag or if I can, I use steel tape (A/C duct work tape) to cover any open holes.
As you found out, over tight is not over good.
When you put it back together just clean everything really well with Brake Parts Cleaner, then assemble it.
As you found out, over tight is not over good.
When you put it back together just clean everything really well with Brake Parts Cleaner, then assemble it.
Thanks guys all excellent suggestions which I will execute on. I was sick to my stomach when this happened and pretty angry at myself to boot.. But I figure I will take tonight off and take a swing at this tomorrow with a clear mind. I also have the replacement studs and bolts on order with my local Kubota dealership so with luck this will be behind me by the end of the weekend. I guess I have to pay the stupid tax on this one, valuable lesson learned!
Thanks again and I will let you know how it goes.
Thanks again and I will let you know how it goes.