Kubota B7100 D750 engine, New rings, head, injectors(from Kubota) and glow plugs. When starting engine its smokes a lot out muffler and is hard to start. Engines sputters and dies. After half dozen tries warming the glow plugs before each try it starts and runs fine at idle and mid range speeds. At high rpm’s engine cuts out some. Bought tractor not running and looks like it had been sitting in the weeds. While running I crack the fuel line at each injector and get an even drop across all cylinders. Starts fine once it has been running and warmed up. I know the glow plugs are working by the indicator on the dash and that it won’t start at all with out glow plugs. Any advice would be appreciated.
B7100 hard to start
- Thread starter Little orange tractor fan
- Start date
Gotta ask the obvious - clean fuel tank, new fuel filters, new air filter, fuel pump checked/replaced, etc.?
Interesting theory that you can see glow plug current on the dash board indicator.
New head: how is your valve play? Camshaft timing correct?
New head: how is your valve play? Camshaft timing correct?
North Idaho Wolfman
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Sounds like the timing is off.
Have you pulled the injection pump out?
Or does it look like anyone else has pulled the injection pump out.
Have you done a spill test?
Have you done a compression test?
Did you use an OEM head gasket?
Have you pulled the injection pump out?
Or does it look like anyone else has pulled the injection pump out.
Have you done a spill test?
Have you done a compression test?
Did you use an OEM head gasket?
Valves are set. Did a compression test on it and getting 200 to 250 psi. I’m questioning if i might have got the timing off 1 tooth. Honed cylinders with new pistons and rings, new head complete with valves. After it warms up smoke goes away and it seems to run good. Could the compression be low if the rings haven’t seated yet?
whitetiger
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North Idaho Wolfman
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Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Did you measure the cylinders?
If they were already large, honing them would just have made them bigger.
Yea as @whitetiger said that's really low compression and it shouldn't start at all.
Normally if the timing is off it won't start, but anything is possible.
Did you use and OEM head gasket?
If they were already large, honing them would just have made them bigger.
Yea as @whitetiger said that's really low compression and it shouldn't start at all.
Normally if the timing is off it won't start, but anything is possible.
Did you use and OEM head gasket?
Engine was completely torn down so injector pump was removed,but reinstalled with same shim. Had machine shop look at block and was recommended to hone and put new standard pistons in. Compression test done cold and i did not do a wet test. Will check the valves, warm it up and do a wet and dry compression test when I get a chance. Thank for the feedback.