fuel injection pump question

[Philngruvy]

I have a 1986 751 with the Peugeot diesel engine. I was unable to get it to start and found that the fuel tank was heavily contaminated with water and sludge. I drained and flushed the tank, installed a new fuel filter and I still can't get it to start. I have verified that fuel is making it to the solenoid fuel shut off valve. However, when I crack open the fuel line to the injectors, to bleed them, no fuel is pumping out. I suspect that my injection pump may have failed. How can I determine the exact cause and what do I need to do to fix it. I greatly appreciate any help/suggestions. Thanks, Ron

 

[Tazza]

You are sure you are getting power to the small coil on the pump? This is the fuel shut off solenoid.
Give the hand primer a good pump and see if you get any fuel out of the injector lines when cranking. You did bleed it with the bleed screw on the pump? no bubbles coming out?

 

[Philngruvy]

You are sure you are getting power to the small coil on the pump? This is the fuel shut off solenoid.
Give the hand primer a good pump and see if you get any fuel out of the injector lines when cranking. You did bleed it with the bleed screw on the pump? no bubbles coming out?

I got approximately 12 volts at the fuel shut off solenoid. I also tried removing the plunger inside the valve, which would allow unimpeded flow of fuel. This was a trick that a Bobcat guy in Tampa showed me years ago. At that time the solenoid quit working and when he came out to troubleshoot it, he removed the plunger and the engine then started. Only problem was that I had to physically pinch the fuel line to shut off the engine. So I don't think my problem is the fuel solenoid valve. Ok, I am not sure what the hand primer is. Can you point me to it. Do you mean to actually pump the hand primer while cranking the engine? I bled the fuel line coming out of the fuel filter into the injector pump with the bleed screw while squezing the hand bulb which is before the fuel filter. I got a solid stream of fuel at this point. I them cracked open the fuel line at the injector while cranking the engine. Nothing came out. So then I took the same injector line loose at the side of the pump and cranked the engine, nothing came out. I hope this does not mean the pump has gone bad. I need more help please.

 

[Tazza]

I got approximately 12 volts at the fuel shut off solenoid. I also tried removing the plunger inside the valve, which would allow unimpeded flow of fuel. This was a trick that a Bobcat guy in Tampa showed me years ago. At that time the solenoid quit working and when he came out to troubleshoot it, he removed the plunger and the engine then started. Only problem was that I had to physically pinch the fuel line to shut off the engine. So I don't think my problem is the fuel solenoid valve. Ok, I am not sure what the hand primer is. Can you point me to it. Do you mean to actually pump the hand primer while cranking the engine? I bled the fuel line coming out of the fuel filter into the injector pump with the bleed screw while squezing the hand bulb which is before the fuel filter. I got a solid stream of fuel at this point. I them cracked open the fuel line at the injector while cranking the engine. Nothing came out. So then I took the same injector line loose at the side of the pump and cranked the engine, nothing came out. I hope this does not mean the pump has gone bad. I need more help please.

The hand primer i was talking about was the one you squeeze, so you have already tried that.
You can always try having someone pump it up to give you some extra pressure, then crank and see if anything comes out.
As you have also removed the plunger in the pump to disable the fuel shut off, you have ruled that out too.... There really isn't a whole lot else you can do short of getting the pump looked at.
The timing belt isn't broken is ist? still moveing the pump pulley?
Sadly, i don't have a lot more i can suggest. They do have an internal fuel pump, but if you use the hand primer bulb to give you pressure and that there is a good air-free stream from the bleed screw. You have done everything right.

 

[Fishfiles]

I don't think I ever worked on or even seen a Peugeot around here , but I have seen when there was a lot of water and dirt in the system and after cleaning it out and refilling that Kubota's wouldn't start , it was because large quanities of water wouldn't pass thru the nozzles on the injector pump , I would just loosen up the fittings going into the pump and spin it over till fuel came out clean , close them off and bleed the injectors

 

[Philngruvy]

I don't think I ever worked on or even seen a Peugeot around here , but I have seen when there was a lot of water and dirt in the system and after cleaning it out and refilling that Kubota's wouldn't start , it was because large quanities of water wouldn't pass thru the nozzles on the injector pump , I would just loosen up the fittings going into the pump and spin it over till fuel came out clean , close them off and bleed the injectors

Ok, which fittings are you referring to? There are four lines coming off the pump which go to the four injectors. Are these the fittings you are referring to? Would it be safe to blow compressed air into these fittings (opposite direction that the fuel would flow) to blow backwards any water gunk that could be plugging the nozzle?

 

[Philngruvy]

Ok, which fittings are you referring to? There are four lines coming off the pump which go to the four injectors. Are these the fittings you are referring to? Would it be safe to blow compressed air into these fittings (opposite direction that the fuel would flow) to blow backwards any water gunk that could be plugging the nozzle?

Also, Timing belt seems to be fine. I turned it over slowly looking for stripped teeth etc. every thing looks good.

 

[7LBSSMALLIE]

Also, Timing belt seems to be fine. I turned it over slowly looking for stripped teeth etc. every thing looks good.

pull valve cover see if cam split in half(common)

 

[7LBSSMALLIE]

Also, Timing belt seems to be fine. I turned it over slowly looking for stripped teeth etc. every thing looks good.

pull valve cover see if cam split in half(common) let others know

 

[bobbie-g]

pull valve cover see if cam split in half(common) let others know

PhilNGruvy, First I thought the Pug engines were only used somewhere around '95 and '96 for two years. If you call Melroe with your S/N they can tell you the year of mfg, not that it really matters. I have a '95 751 with the Pug engine. I had to replace the fuel injector pump, $1350 for the pump from Bobcat. I should have had it rebuilt for half that. The lift pump is integral in the injector pump housing. When mine went bad (lift pump only), it would run with someone squeezing the primer bulb continuously to get fuel up to the pump. The primer bulb should be right below the fuel filter, in the line that feeds the filter. --- To see if you're getting fuel, you should be able to crack the 17mm nuts loose right at the cylinders on each of the 4 lines. Fuel should squirt out around each of the nuts when you spin the engine. To flush out all the water, etc, you could remove all 4 lines and blow them out, then spin it and let fuel squirt out the pump all over the place until the fuel is clean. --- I sure don't know, but I would just guess that all of the injectors didn't clog all at once. Seems like if the injector pump were working, it should at least fire on one or two cylinders. --- Bobbie G.

 

[Philngruvy]

PhilNGruvy, First I thought the Pug engines were only used somewhere around '95 and '96 for two years. If you call Melroe with your S/N they can tell you the year of mfg, not that it really matters. I have a '95 751 with the Pug engine. I had to replace the fuel injector pump, $1350 for the pump from Bobcat. I should have had it rebuilt for half that. The lift pump is integral in the injector pump housing. When mine went bad (lift pump only), it would run with someone squeezing the primer bulb continuously to get fuel up to the pump. The primer bulb should be right below the fuel filter, in the line that feeds the filter. --- To see if you're getting fuel, you should be able to crack the 17mm nuts loose right at the cylinders on each of the 4 lines. Fuel should squirt out around each of the nuts when you spin the engine. To flush out all the water, etc, you could remove all 4 lines and blow them out, then spin it and let fuel squirt out the pump all over the place until the fuel is clean. --- I sure don't know, but I would just guess that all of the injectors didn't clog all at once. Seems like if the injector pump were working, it should at least fire on one or two cylinders. --- Bobbie G.

Bobbie-g, thanks for the reply. I have good fuel flow to the pump. Plenty of flow at the solenoid fuel shut off and yes the solenoid is good and working properly. I have blown out the injector supply lines. I have squeezed that doggone primer bulb until my arthritic fingers are aching, both with the engine turning over and with it not turning over. If you follow the lines down from the injectors in the head, they end up at the injector pump (I think that is the proper term for it). There are four of them (fuel supply lines) and they connect at the end of the unit that I am calling the injector pump. No fuel is coming out of that connection. I took all four loose, blew out the lines to the injectors. They are clear. I took the solenoid switch off, and blew air backwards from the supply line connection and I got bubbles in the pool of fuel that is in the hole where the solenoid goes. I blew all four the same way and got bubbles everytime. Now I did not get a strong stream of air flow, just a good amount of fine bubbles. I also blew air into the solenoid hole and did not get any results. All this info leads me to believe that the problem is within the injector pump.. Whqt do you or anyone else think? I am in a remote area of Western NC with the machine and Bobcat of Asheville tells me that the trip alone is going to cost me 2-3 hundred dollars alone. OUCH!!!!!!!!!!!!!!! Where the machine is, I cant even get my flatbed trailer down to load it up. Well I could if the Bobcat was working, LOL. I need help, divine or otherwise!!!!!!!!!!

 

[bobbie-g]

Bobbie-g, thanks for the reply. I have good fuel flow to the pump. Plenty of flow at the solenoid fuel shut off and yes the solenoid is good and working properly. I have blown out the injector supply lines. I have squeezed that doggone primer bulb until my arthritic fingers are aching, both with the engine turning over and with it not turning over. If you follow the lines down from the injectors in the head, they end up at the injector pump (I think that is the proper term for it). There are four of them (fuel supply lines) and they connect at the end of the unit that I am calling the injector pump. No fuel is coming out of that connection. I took all four loose, blew out the lines to the injectors. They are clear. I took the solenoid switch off, and blew air backwards from the supply line connection and I got bubbles in the pool of fuel that is in the hole where the solenoid goes. I blew all four the same way and got bubbles everytime. Now I did not get a strong stream of air flow, just a good amount of fine bubbles. I also blew air into the solenoid hole and did not get any results. All this info leads me to believe that the problem is within the injector pump.. Whqt do you or anyone else think? I am in a remote area of Western NC with the machine and Bobcat of Asheville tells me that the trip alone is going to cost me 2-3 hundred dollars alone. OUCH!!!!!!!!!!!!!!! Where the machine is, I cant even get my flatbed trailer down to load it up. Well I could if the Bobcat was working, LOL. I need help, divine or otherwise!!!!!!!!!!

OK, Phil... Here's another test you can try. Get a gallon can of clean diesel and some 5/16" hose. Take the primer bulb out of the line on the 751 (don't let the supply end of the hose disappear under the engine!). Connect a couple of lengths of hose to the primer. Put one hose in the can and pump the bulb to make sure you get a good flow of diesel out the other end. Then connect the output line directly to the injector pump. Now pump the primer whilst having your assistant spin the motor. You should get fuel leaking around any of the 4 lines that connect from the injector pump to the block (if you have them loosened). If not, I think you've done everything I know to eliminate all problems except a bad injector pump. You've even at this point eliminated the low-pressure lift pump that's inside the injector pump. I know you've said you checked the timing belt to ensure it's actually rotating the injector pump gear. I'm at a loss to think of anything else to check. Them thar pumps ain't cheap. If the preceding doesn't result in fuel coming out of the injector pump into each of the 4 lines, then I think the next step is to remove the pump and take it to an industrial diesel repair shop. I think the local shop in Albuquerque wanted about $700 to rebuild my pump, new one was $1300+ from Bobcat. What's anyone else on the forum think? Let's not let Phil... go this route if there's something else that should be tried first....... ---Bobbie G.

 

[7LBSSMALLIE]

OK, Phil... Here's another test you can try. Get a gallon can of clean diesel and some 5/16" hose. Take the primer bulb out of the line on the 751 (don't let the supply end of the hose disappear under the engine!). Connect a couple of lengths of hose to the primer. Put one hose in the can and pump the bulb to make sure you get a good flow of diesel out the other end. Then connect the output line directly to the injector pump. Now pump the primer whilst having your assistant spin the motor. You should get fuel leaking around any of the 4 lines that connect from the injector pump to the block (if you have them loosened). If not, I think you've done everything I know to eliminate all problems except a bad injector pump. You've even at this point eliminated the low-pressure lift pump that's inside the injector pump. I know you've said you checked the timing belt to ensure it's actually rotating the injector pump gear. I'm at a loss to think of anything else to check. Them thar pumps ain't cheap. If the preceding doesn't result in fuel coming out of the injector pump into each of the 4 lines, then I think the next step is to remove the pump and take it to an industrial diesel repair shop. I think the local shop in Albuquerque wanted about $700 to rebuild my pump, new one was $1300+ from Bobcat. What's anyone else on the forum think? Let's not let Phil... go this route if there's something else that should be tried first....... ---Bobbie G.

pull the pump send too local inj shop they will tell its toast.(note on these run it dry once and its done)

 

[Philngruvy]

pull the pump send too local inj shop they will tell its toast.(note on these run it dry once and its done)

Still have not gotten it to work. How hard is it to rebuild the pump? I am somewhat mechanically inclined and I just dont have the $$$$ to pay someone to rebuild it if it is something that I can do myself. Does anyone have a blowup picture of the pump and it inner workings? I would love to see what is inside without tearing it apart first. Or am I just dreaming?

 

[tnt6060]

Still have not gotten it to work. How hard is it to rebuild the pump? I am somewhat mechanically inclined and I just dont have the $$$$ to pay someone to rebuild it if it is something that I can do myself. Does anyone have a blowup picture of the pump and it inner workings? I would love to see what is inside without tearing it apart first. Or am I just dreaming?

It takes speical tools & you would have a hard time getting parts check with pump rebuilder before you take it off I am not familiar with your engine some have timing marks you should line up before removing.