Anyone in the long beach california area know any good experienced diesel mechanics ? i have a problem with my 2 cyl yanmar, it was smoking a bit at high revs (black smoke) so i had the motor serviced and valves adjusted but was still a little smokey over 2500 revs so we took out the injectors and had them rebuilt but when they were put back in it was smoking 100x worse and was only working on 1 cylinder, so i then had the injection pump rebuilt but when it was put back in both cylinders were working but still loads of smoke and soot coming out and the revs were running uncontrolably high and wouldnt shut off with the engine stop switch, any suggestions would be appreciated or any recomendations, is there anyway the pump or injectors could have been rebuilt wrong? The shop that done them do that for a living so i would assume they had done them correctly
Any good Diesel mechanic recomendations for this problem?
- Thread starter wilf
- Start date
Black smoke seems like too much fuel. If it is an older model Yanmar, one that uses a fuel return line, it is possible that it has a restriction - kink in the line, sludge coating the inside of the line, something like that. If there is no kink-type restriction, suggest just replacing it and rodding the connection where it goes into the tank to ensure that part is wide open, too. There could also be a coating in the banjo line between the two injectors but taking it off would require new copper washers so try the hose line first. Coast Guard approved has a much thicker wall than OEM stuff.
Disclaimer [Must read!]: I'm no engine mechanic and don't even claim to be any good at it.
Disclaimer [Must read!]: I'm no engine mechanic and don't even claim to be any good at it.
Thanks, just seems strange that it was 100x worse once we put the rebuilt injectors in
I'm not a diesel mechanic either. Did you check the exhaust elbow ? Not being able to shut it down suggests a problem with the injector pump or its running on lub oil being sucked up around the piston rings. Was it consuming oil before this problem began ? Was a compression test done on the engine while the injectors were being serviced ?
It is possible the high pressure pump was not properly serviced. Was the injection timing checked after the pump was replaced ?
Bob
It is possible the high pressure pump was not properly serviced. Was the injection timing checked after the pump was replaced ?
Bob
So my black smoke at higher rpm' was not an angina problem but a prop issue. I was over propped which prevented the engine from reaching high rpm under load. When at the dock do you get black smoke at high rpm in neutral? What happens at the same rpm when in gear.
Can't solve the current issues after the rebuild but next time before you dig into the engine check the entire drive train
Good luck
Can't solve the current issues after the rebuild but next time before you dig into the engine check the entire drive train
Good luck
Going to chec
Going to check the exhaust elbow today, it wasnt using oil before that i know of, the compression was fine i assumed the injection timing was something in the pump that was checked at the diesel shop ?
What motor are we talking about here? When did throttle control problem start? Do you have a shop manual for the motor? Did you reassemble the parts in strict accordance with the manual?
Your exhaust elbow is not causing the throttle control symptoms. However, you do need to make sure it is clear of restrictions - both the water and exhaust passages.
Inability to stop or running uncontrollably high means that fuel to the motor is not being controlled. Two of the usual suspects: The injection pump fuel rack is not engaged with the throttle cable lever/governor properly or possibly the governor assembly is allowing fuel despite the fuel control position. The second way this happens is fuel from some other source - usually the crankcase. This can happen if fuel gasses are forced into the crankcase (perhaps because of piston rings failure or maybe through a broken lift pump diaphragm) then forced out via the crankcase breather and consumed via the air intake.
Verify the throttle mechanism is engaged, with the pump in its referenced position, and that the governor mechanism is intact and operative. All of this is reasonably simple and will be shown in the shop manual. Verify also that you have compression in both cylinders. The shop manual will give you expected values. Double check the valve lash thus to be sure an exhaust valve adjuster lock nut has not come loose.
Charles
Your exhaust elbow is not causing the throttle control symptoms. However, you do need to make sure it is clear of restrictions - both the water and exhaust passages.
Inability to stop or running uncontrollably high means that fuel to the motor is not being controlled. Two of the usual suspects: The injection pump fuel rack is not engaged with the throttle cable lever/governor properly or possibly the governor assembly is allowing fuel despite the fuel control position. The second way this happens is fuel from some other source - usually the crankcase. This can happen if fuel gasses are forced into the crankcase (perhaps because of piston rings failure or maybe through a broken lift pump diaphragm) then forced out via the crankcase breather and consumed via the air intake.
Verify the throttle mechanism is engaged, with the pump in its referenced position, and that the governor mechanism is intact and operative. All of this is reasonably simple and will be shown in the shop manual. Verify also that you have compression in both cylinders. The shop manual will give you expected values. Double check the valve lash thus to be sure an exhaust valve adjuster lock nut has not come loose.
Charles
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Thanks Charles, the mechanic that was doing the work had to fly back to misouri so couldnt finish it but he did mention the governer , i dont understand how that became a problem after the injectors and pump were re done? , all the smoke started when the rebuilt injectors were just re-installed before the pump was even touched but he said he thought when he took out the injection pump to see what was causing the smoke something happened so thats why i got the pump rebuilt, the diesel shop said not to do anything to the pump just refit it as it is, we thought the barrel that moves side to side on the side of the pump was in the wrong place but we checked and it was correct, do you know what could have altered the governers setting ? Should the timing have been checked before instaling the injectors or before instaling the pump?
I am sure you recognize that no one can offer a definitive diagnoses from afar. Nor can one explain what to do absent an opportunity to conduct a on site examination because the symptoms so far are just too vague.
You have two options - find someone who knows the score. Ask your dock neighbors, the dock office - better - ask the firm that did the injectors/pump for a reference. The second option is for you to read and understand everything in the fuel control and governor chapters of the shop service manual for your motor. In other words - you personally need to learn how things work before you can expect to locate what isn't working and fix it. I can imagine no other options that will be helpful.
If you do not have a manual I can probably send you one. But either way having someone who knows the score explain what the manual is driving at will be invaluable to you.
Charles
You have two options - find someone who knows the score. Ask your dock neighbors, the dock office - better - ask the firm that did the injectors/pump for a reference. The second option is for you to read and understand everything in the fuel control and governor chapters of the shop service manual for your motor. In other words - you personally need to learn how things work before you can expect to locate what isn't working and fix it. I can imagine no other options that will be helpful.
If you do not have a manual I can probably send you one. But either way having someone who knows the score explain what the manual is driving at will be invaluable to you.
Charles
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Its really frustrating as My post is actually to find a mechanic in my area so far ive called 4 people and none return my calls another one was supposed to show up this morning but didn't , im a general contractor and if people call me i tell them straight off if i can do it or not
Wish I could help - meanwhile don't overlook the yanmar tractor/yard implement dealers for additional leads. Here is a reliable version of the service manual - maybe same as the one you already have.
Ooops cannot send manual - too big. PM your e mail and I will send it there.
Charles
Ooops cannot send manual - too big. PM your e mail and I will send it there.
Charles
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My guess is there are two things. Restricted air intake thus not enough air volume/fuel unit (over fueling smoke.) Or restricted exhaust path resulting in spent gasses not escaping (back pressure) rpm unable to rise. Governor assembly provides more fuel to make rpm rise but exhaust restriction cannot expel thus rpm cannot rise (over fueling smoke.)
In any case 'runaway' or throttle control symptoms are separate from soot/smoke symptoms. Governor lever does not engage rack correctly, governor springs fail, throttle control not positioning for expected rpm.
IOW over fueling soot/smoke symptoms are separate from more recent (not seen before) erratic throttle control symptoms. What say you?
Charles
In any case 'runaway' or throttle control symptoms are separate from soot/smoke symptoms. Governor lever does not engage rack correctly, governor springs fail, throttle control not positioning for expected rpm.
IOW over fueling soot/smoke symptoms are separate from more recent (not seen before) erratic throttle control symptoms. What say you?
Charles
agree with Charles, black smoke is unburned fuel so either too much fuel for the air or too little air for the fuel. Intake restriction, exhaust restriction (can't get it in if you can't get it out first) or fuel system. since the injector service made a big change I'm thinking that somebody screwed the pooch on the reinstall or the actual injector service. Check the fuel lines first.
There are a lot of good suggestions earlier in this thread and the problem could be most any one of them. Like what was said earlier, without knowing what the mechanic did pretty much any of the suggestions could be the cause of the problem.
With regard to the fuel line, that was my thought way in the beginning. The fuel return line is the "low hanging fruit" check: no cost and if it's the problem then it's a cheap fix. This is something almost anyone can do. Pretty much everything else you're looking at will be expensive and, this time of year, require a difficult to find and technically capable mechanic.
1. At the top of the injectors is a banjo fitting that is connected by a metal tube, and the rear injector's banjo is where the fuel return line is connected and secured with a clamp. If the clamp was removed then later reinstalled but aft of the barbed fitting (Note: can be difficult to get the hose on) it will have constricted the hose at that point and prevent fuel being returned to the tank. The build up in fuel pressure here will force fuel into the injector and, hence, into the cylinder. Hmmm.... this gives me another thought, see par. #4
2. The next thing to look at is the path of the fuel return line to see if there is a kink, or, heaven forbid, a shutoff valve where it attached to the tank. (a) There shouldn't be one but who knows, and it could be closed. (b) Maybe someone removed the hoses on the tank then reconnected them in reverse? [Edit: the latter not likely because the fuel tank connection for the return line should not have a pickup tube.]
3. If the hose is old there could be a coating on it's inside, same kinda stuff as on the inside of an old fuel tank. Solution is it replace the hose.
4. Later in this thread it was mentioned about one cylinder running. Maybe something was wrong with the installation of the banjo fitting that would have plugged one of the holes where the return fuel goes? Not sure how this could happen but if the bolt with it's hole and recessed area doesn't align with the banjo the fuel won't flow. All I can say here is that *stuff* can happen.
5. One other item not mentioned in the thread's laundry list of possibilities is a leaky fuel pump diaphragm. A hole in the diaphragm will cause fuel to get into the oil pan, dilute the oil, and then bypass the rings to get burnt. Doubt this is likely because the fuel pump wasn't touched. If not the fuel line, most likely the problem was caused by something that was touched when things were "fixed". Air filter: is it still there or did it get ingested?
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Thinking about the problem some more, an earlier post mentioned that the mixing elbow could be a problem and, although the severe smoke problem, as I understood it, seemed to happen so suddenly, I kinda dismissed it. However, that is something to check - doesn't cost anything BUT can be an effort to do. When the mixing elbow starts getting clogged it can happen rather fast toward the end. So, as a no-cost (but work) to check, I'd go for it.
The other thing, the second cylinder not working: was there an attempt to bleed the injector again? Were new banjo washers put in? If they were re-used it's possible there is an air leak. Was there any sign of a fuel leak around the second injector? Kleenex wadded around the thread connections is a good way to tell if there is any fuel present.
The other thing, the second cylinder not working: was there an attempt to bleed the injector again? Were new banjo washers put in? If they were re-used it's possible there is an air leak. Was there any sign of a fuel leak around the second injector? Kleenex wadded around the thread connections is a good way to tell if there is any fuel present.
curious as to whether they checked for sticky valves, bad valve seats or guides before tearing into th injectors. 1) did the original shop have the equipment to calibrate the injector pump? and did they pull the pump, fit it onto the calibration machine, and operate it to check condition? (on the GMs the control rack arm needs to be moved to pull this pump , so rack arm needs to be set back into its original position. did they?) did they adjust the timing and properly reinstall the injector pump ??? 2) get them to check the governor link assembly whose lever mates to the fuel control rack for sticking sleeve?or fuel control sleeve failure ? also check for bad regulator spring. if this goes bad the movement of the fuel control rack may be affected adversely. check for a bad engine stop spring too. (all of this is from Mack Boring's Adv Engine diagnostics class materials.) 3) in my experience , mixing elbow clogs show as loss of power from the normal power curve and develop slowly over a time, not abruptly after an injector rebuild. I'd see if the shop who did the original work is a certified yan mar dealer. call yan mar regional service, check that, and get the name of a shop who is. you may also find it worthwhile to subscribe for a year to boat diesel.com. once you are a member, you can post your issue to their board, and get very experienced mechanics giving freely of their time and knowledge to weigh in on your issue . armed with that info , you should start negotiating with the top person at the shop who did your original work. IMHO few other shops will want to touch something the original shop screwed up at all, let alone at a reasonable price...
Those high rise exhaust elbows can clog in as little as 300 hrs. I'd sure check it.
I do know an excellent mechanic in Capo Beach, not sure if he'll go up to Long Beach. He will return your call promptly, he's good enough that he's usually booked for a couple weeks ahead. However, many times he has been able to help over the phone, I'm sure he'd suggest checking the elbow before proceeding. Google John Ross Marine for a phone number.
I do know an excellent mechanic in Capo Beach, not sure if he'll go up to Long Beach. He will return your call promptly, he's good enough that he's usually booked for a couple weeks ahead. However, many times he has been able to help over the phone, I'm sure he'd suggest checking the elbow before proceeding. Google John Ross Marine for a phone number.