ok, went to start the M-120, engine turned over and about the time it should have started it popped. I let off key immediately, tried again and nothing wouldn't turn over. Tried again and it cranked but ran rough and had blue smoke. I could tell it was from one cylinder and acted like a injector. Assuming one had blew i started cracking lines one at a time and sure enough the back on when cracked made it quit smoking. Pulled the injector, took it to reputable shop and sure enough it was stuck open. They cleaned it but the nozzle wasn't spraying right. Got new nozzle and re installed today. Bled it up and cranked. Blue smoke again. Ok needed to let run and work everything out so I let it warm and ran it at max rpm for about 5 mins. I heard it clear up and it ran fine. After engine cooled and was restarted it is doing it again, slight skip at 1000 to 1500 rpm and popping smoke. Crack that injector line and smoke clears. This was repeated all day. Please provide any suggestions. I am at loss.
injector or what??
- Thread starter kubota9
- Start date
well swap injectors with another one to see if the problem followed the injector, it didn't. So now i am looking at a possible delivery valve in the pump. Now for the hard one... does anyone know where I can get one of the special pullers that pulls the autotimer and pump gear from the front. No dealers have one that I can find. Said they never have had to pull a Zexel pump on one. Just my luck....
Could be the delivery valve or it's possible it's a valve or ring problem that's only appearing when you're getting combustion. Who knows how long that injector was misfiring in there, could have damaged something. Compression test would be my next stop before I start messing with the pump. What's special about the puller you need? I'd have thought a regular 3 jaw would be sufficient for most anything on these machines. I have little knowledge of that particular engine family so I'm just postulating.
Thanks Stumpy, yeah I did a compression test today. Back cylinder is averaging 100 lbs low. Looks like when that injector stuck open it dumped alot of fuel in that cylinder and when it popped I am suspecting it bent a rod. The piston may not be getting full stroke which is causing incomplete cumbustion. Either way I have to tear into it and see. Not what I wanted to do. Still weighing whether to do it myself or just pay the labor. If that engine had a oil pan that would drop without splitting the tractor I would do it in a heart beat. Thanks for your reply.
oh. The puller looks like a short piece of pipe that has threads on the outside of one end, these screw into the gear. Than it had a bolt and threads that run inside it to push off the gear. Only has about 1/16th clearence around the outside of the gear so jaw type is no go.
oh. The puller looks like a short piece of pipe that has threads on the outside of one end, these screw into the gear. Than it had a bolt and threads that run inside it to push off the gear. Only has about 1/16th clearence around the outside of the gear so jaw type is no go.
You could commission Wildfire to make you a puller. Or, someone local to you who has similar skills.
100lbs down huh? The rod might be bent but I'll bet it survived fine though the bearings probably have some good scrapes. You'll probably find the piston lands smashed and the bore scared but if you're lucky the valves won't have ingested any metal or overheated.