751 starting problem

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Philngruvy

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I have a 1996 751 with the Peugot engine in it. One morning last week, I was working with it and it stated great, no problem. I left to go do another errand and when I came back, it simply would not start. Plenty of fuel in it. I checked the fuel shutoff solenoid and it was not the problem. I am at a loss to what the problem is. I need help. Any suggestions? Thanks, Ron
 

bobbie-g

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Ron, send me an email so we can link up. I have essentially the same model Bobcat. Does it have fuel in the tank (sorry, I just had to ask, I've pulled some really dumb stunts in my time!) Ok, first, is the engine spinning? Assuming it is, let's make sure it has fuel to the injectors. There should be 12v or so on the fuel shutoff solenoid, AND the solenoid obviously must be open/retracted when that 12v is applied (burned out coil or mechanical binding would not allow the solenoid to retract and allow fuel flow, even if 12v was available right at the terminal on the coil). Using a 17mm wrench, try cracking loose an injector line right at one of the injectors and spin the engine for a few seconds. You should get a good quantity (tablespoonful?) of fuel coming out. If no fuel, let's look at the injector pump. Our particular model has a lift pump integral with the high-pressure injector pump. If the lift pump is not working, no fuel to the injectors. A way to test that is to pressurize the inlet side of the pump by manually squishing the primer bulb several times while spinning the engine, and see if it starts. And a way to ensure you have fuel to the inlet of the pump is to use an 8mm wrench to loosen the teensy bleed orfice right at the inlet to the pump. With that loosened, you should be able to manually pump fuel right through the filter, up the line, and out the bleed orfice. While we're at it, let's loosen the water drain on the bottom of the fuel filter to make sure we've dumped out the water (most I've ever gotten out of mine was about half a teaspoonful). So much for the fuel deal. If all that works, maybe the glowplug circuitry when south. You should be able to see the glowplug amber light, right up by the key switch, stay on for about 5 seconds after key-on, then go out. You should hear a relay click a couple of seconds after that, at exactly the same time as your voltmeter jumps up half a volt or so, indicating the power to the glowplugs has just stopped. That means you probably have power to the glowplugs. Another way to check is to connect a voltmeter right to the wire that connects all four glowplugs together. You should see about 11 or 12v on that line for about 10 seconds after the key is turned on. Lastly, is there any smoke coming out while you are cranking? If you're squirting in fuel and the glowplugs are hot, it must at least pop or stutter a few times. Unless your timing belt broke. We'll tackle that possibility after you run through the above. If this seems too involved, I'll shoot you back a phone number after I get your email adr. Good luck, ---Bob
 

Tazza

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Ron, send me an email so we can link up. I have essentially the same model Bobcat. Does it have fuel in the tank (sorry, I just had to ask, I've pulled some really dumb stunts in my time!) Ok, first, is the engine spinning? Assuming it is, let's make sure it has fuel to the injectors. There should be 12v or so on the fuel shutoff solenoid, AND the solenoid obviously must be open/retracted when that 12v is applied (burned out coil or mechanical binding would not allow the solenoid to retract and allow fuel flow, even if 12v was available right at the terminal on the coil). Using a 17mm wrench, try cracking loose an injector line right at one of the injectors and spin the engine for a few seconds. You should get a good quantity (tablespoonful?) of fuel coming out. If no fuel, let's look at the injector pump. Our particular model has a lift pump integral with the high-pressure injector pump. If the lift pump is not working, no fuel to the injectors. A way to test that is to pressurize the inlet side of the pump by manually squishing the primer bulb several times while spinning the engine, and see if it starts. And a way to ensure you have fuel to the inlet of the pump is to use an 8mm wrench to loosen the teensy bleed orfice right at the inlet to the pump. With that loosened, you should be able to manually pump fuel right through the filter, up the line, and out the bleed orfice. While we're at it, let's loosen the water drain on the bottom of the fuel filter to make sure we've dumped out the water (most I've ever gotten out of mine was about half a teaspoonful). So much for the fuel deal. If all that works, maybe the glowplug circuitry when south. You should be able to see the glowplug amber light, right up by the key switch, stay on for about 5 seconds after key-on, then go out. You should hear a relay click a couple of seconds after that, at exactly the same time as your voltmeter jumps up half a volt or so, indicating the power to the glowplugs has just stopped. That means you probably have power to the glowplugs. Another way to check is to connect a voltmeter right to the wire that connects all four glowplugs together. You should see about 11 or 12v on that line for about 10 seconds after the key is turned on. Lastly, is there any smoke coming out while you are cranking? If you're squirting in fuel and the glowplugs are hot, it must at least pop or stutter a few times. Unless your timing belt broke. We'll tackle that possibility after you run through the above. If this seems too involved, I'll shoot you back a phone number after I get your email adr. Good luck, ---Bob
An easier way to check for fuel is when its cranking, is it puffing white smoke? if not, your not getting any fuel.
I was going to say these engines have a fuel pump inside the injector pump but Bob beat me to it. It can be a nightmare when they leak, the diesel fills the crank case of the engine!!
 

skidsteer.ca

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Any smoke coming from it when you crank it over. Indicates that its getting fuel. You tried a new fuel filter already?
Ken
 

bobbie-g

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Any smoke coming from it when you crank it over. Indicates that its getting fuel. You tried a new fuel filter already?
Ken
Tazza, I've heard elsewhere that a leaky fuel pump will fill the crankcase with fuel. But on this machine, the entire pump is external, driven by a sprocket which engages the timing belt. I don't see any way fuel can make it into the crankcase. BTW, Bobcat gets $1345 US for a new fuel pump. I really didn't want to be in a position to know that! And if anyone wants a used one with a bad lift pump, I can help! --- Ron, I forgot to include my email address. [email protected] ---Bob
 

Philngruvy

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Tazza, I've heard elsewhere that a leaky fuel pump will fill the crankcase with fuel. But on this machine, the entire pump is external, driven by a sprocket which engages the timing belt. I don't see any way fuel can make it into the crankcase. BTW, Bobcat gets $1345 US for a new fuel pump. I really didn't want to be in a position to know that! And if anyone wants a used one with a bad lift pump, I can help! --- Ron, I forgot to include my email address. [email protected] ---Bob
Thanks for all the responses. Yes the fuel tank is full, I recently replaced the fuel filter and I have drained the fuel filter and found no water in it. I removed the plunger in the fuel shutoff solenoid. This went bad on me before with the machine in the middle of the street. FYI, Bobcat charged me approximately $150 for a new solenoid. I thought they must be very proud of that little unit. I never thought about looking for any other alternate source for a cheaper replacement. I have read on this forum about the $9 glow plugs at Autozone vs. $36 by Bobcat and I thought maybe I paid too much for the solenoid. Anyway, that is not the problem. I have not checked the voltage to the glow plugs yet but that will be on the top of the list when I get back out to the machine. I did bleed the injector line and did not get the quantity of fuel you mentioned. I did give it a squirt of ether and it would not start even with ether. That really boggles my mind because if the engine was not getting fuel, I would still expect it to start with the ether. So, if the injector pump is bad, what kind of $$ damage am I looking at? Also, as I mentioned in my first post, the engine started immediately that morning but two hours later, nothing. Would the pump go out that fast with no transition between good start to a weak start to no start? Once again, thanks for the help. Ron
 

Tazza

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Thanks for all the responses. Yes the fuel tank is full, I recently replaced the fuel filter and I have drained the fuel filter and found no water in it. I removed the plunger in the fuel shutoff solenoid. This went bad on me before with the machine in the middle of the street. FYI, Bobcat charged me approximately $150 for a new solenoid. I thought they must be very proud of that little unit. I never thought about looking for any other alternate source for a cheaper replacement. I have read on this forum about the $9 glow plugs at Autozone vs. $36 by Bobcat and I thought maybe I paid too much for the solenoid. Anyway, that is not the problem. I have not checked the voltage to the glow plugs yet but that will be on the top of the list when I get back out to the machine. I did bleed the injector line and did not get the quantity of fuel you mentioned. I did give it a squirt of ether and it would not start even with ether. That really boggles my mind because if the engine was not getting fuel, I would still expect it to start with the ether. So, if the injector pump is bad, what kind of $$ damage am I looking at? Also, as I mentioned in my first post, the engine started immediately that morning but two hours later, nothing. Would the pump go out that fast with no transition between good start to a weak start to no start? Once again, thanks for the help. Ron
Usually a pump would slowly go bad, i would still suspect the lift pump if your not getting fuel.
All the lift pump does is draws fuel from the fuel tank and moves it to the injector pump that has tiny pistons that pressurize the fuel. I just don't know how you can test that your lift pump is working.
Does it puff smoke when cranking?
 

bobbie-g

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Usually a pump would slowly go bad, i would still suspect the lift pump if your not getting fuel.
All the lift pump does is draws fuel from the fuel tank and moves it to the injector pump that has tiny pistons that pressurize the fuel. I just don't know how you can test that your lift pump is working.
Does it puff smoke when cranking?
Tazza, the Bobcat folks diagnosed my weak lift pump by pumping on the primer bulb and observing that the engine sped up. I was skeptical, but a few months later it quit running. To load it on the trailer to take it to the Bobcat place, one person had to keep pumping the bulb to keep the engine running while the other drove it onto the trailer. [Not a recommended procedure.] But, I am now convinced that with my model Bobcat, pumping the primer bulb whilst observing engine speed is indeed a correct way to diagnose a weak lift pump. ---Bob
 

Tazza

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Tazza, the Bobcat folks diagnosed my weak lift pump by pumping on the primer bulb and observing that the engine sped up. I was skeptical, but a few months later it quit running. To load it on the trailer to take it to the Bobcat place, one person had to keep pumping the bulb to keep the engine running while the other drove it onto the trailer. [Not a recommended procedure.] But, I am now convinced that with my model Bobcat, pumping the primer bulb whilst observing engine speed is indeed a correct way to diagnose a weak lift pump. ---Bob
I do remember that. It was a while ago now but it makes sense.
 

goodtech

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I do remember that. It was a while ago now but it makes sense.
Check your timing belt on these things, I have had a couple of them slipp a tooth and they will not run, and you will chase your tail thinking it is a fuel problem, Been there and done it., pop that front cover off and make sure that all the lines line up where they need to. Good luck
 

Philngruvy

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Check your timing belt on these things, I have had a couple of them slipp a tooth and they will not run, and you will chase your tail thinking it is a fuel problem, Been there and done it., pop that front cover off and make sure that all the lines line up where they need to. Good luck
Thanks for all the help. After talking to Bobbie on the phone the other day, I am believing that the problem is in the timing belt. The service on the belt is 1600 hours and I am at 1684. And all the other symptoms seem to indicate a bad belt, ie. when I bleed the fuel line at the injectors, I am getting very little fuel. I gues the belt may have stripped some teeth or broken altogether. I have been very busy with other projects, so I have not had time to delve into this problem further. A question for you in the know guys. Assuming that the timing belt is the culprit, is this a job that I should be able to handle myself or do I need to call the experts ($$$$)? Thanks, Ron
 

Philngruvy

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Thanks for all the help. After talking to Bobbie on the phone the other day, I am believing that the problem is in the timing belt. The service on the belt is 1600 hours and I am at 1684. And all the other symptoms seem to indicate a bad belt, ie. when I bleed the fuel line at the injectors, I am getting very little fuel. I gues the belt may have stripped some teeth or broken altogether. I have been very busy with other projects, so I have not had time to delve into this problem further. A question for you in the know guys. Assuming that the timing belt is the culprit, is this a job that I should be able to handle myself or do I need to call the experts ($$$$)? Thanks, Ron
OK, I have been very busy with other problems and I am just now getting back to work on this thing. I called my local Bobcat dealership and the service dept. informed me that labor cost alone to replace the timing belt is $1900.00. OMG!!!!!!!!!!!! Further more, he tells me that it is possible that the head pistons and camshaft may be damaged as the Peugeot engine is an interference engine and that new parts are not available but they can do a retrofit with a different engine. I did not even ask the cost, I was so POed. So, did I get correct info from them or what? Anyone know anthing along these lines?
 

Tazza

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OK, I have been very busy with other problems and I am just now getting back to work on this thing. I called my local Bobcat dealership and the service dept. informed me that labor cost alone to replace the timing belt is $1900.00. OMG!!!!!!!!!!!! Further more, he tells me that it is possible that the head pistons and camshaft may be damaged as the Peugeot engine is an interference engine and that new parts are not available but they can do a retrofit with a different engine. I did not even ask the cost, I was so POed. So, did I get correct info from them or what? Anyone know anthing along these lines?
I would do as goodtech said, pop the cover off and see what the belt looks like.
You should be able to do a job like this on you're own if there are timing marks. If it only did 1 or 2 teeth i can't see it bending valves, but if it broke it could. Start by checking the belt, change it and see what happens. You may be lucky, do the easy stuff first.
*if* it did bend valves, there will only be a few bent, you can get this repaired easily enough and re-fit the head for far less than bobcat want in just labor.
Good luck!
 

Philngruvy

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I would do as goodtech said, pop the cover off and see what the belt looks like.
You should be able to do a job like this on you're own if there are timing marks. If it only did 1 or 2 teeth i can't see it bending valves, but if it broke it could. Start by checking the belt, change it and see what happens. You may be lucky, do the easy stuff first.
*if* it did bend valves, there will only be a few bent, you can get this repaired easily enough and re-fit the head for far less than bobcat want in just labor.
Good luck!
Thanks for the encouraging words. I think I agree to do that . I will post my progress.
 

bobbie-g

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Thanks for the encouraging words. I think I agree to do that . I will post my progress.
Ron, when I had my fuel pump replaced, I had the timing belt replaced at the same time. I believe the labor was not more than $800 for the entire job. Your $1900 figure sure looks suspect to me. --- I've heard there is a Kubota retrofit kit available for our Peugeot engines, but have not looked into it. I've not tried to find many replacement parts for the engine yet, so I don't know what the real story is on how hard it is to find parts. This is the same engine (XUD9) that the Peugeot 306 sedan uses. Of course, there aren't probably that many old junk yard Peugeot sedans with good engines in the US. --- I'm still itching to know if it really is a broken or slipped belt. Maybe you could loosen the timing belt cover just a bit and sneak a peak inside without doing a complete left-side-of-the-engine tear-down. Enquiring minds want to know........--- Bob
 

Philngruvy

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Ron, when I had my fuel pump replaced, I had the timing belt replaced at the same time. I believe the labor was not more than $800 for the entire job. Your $1900 figure sure looks suspect to me. --- I've heard there is a Kubota retrofit kit available for our Peugeot engines, but have not looked into it. I've not tried to find many replacement parts for the engine yet, so I don't know what the real story is on how hard it is to find parts. This is the same engine (XUD9) that the Peugeot 306 sedan uses. Of course, there aren't probably that many old junk yard Peugeot sedans with good engines in the US. --- I'm still itching to know if it really is a broken or slipped belt. Maybe you could loosen the timing belt cover just a bit and sneak a peak inside without doing a complete left-side-of-the-engine tear-down. Enquiring minds want to know........--- Bob
Well-----------, You wont believe it!!!!!!!! I finally got my sorry rearend out back to work on the Bobcat. I took the two topmost covers off the timing belt for a looksee. Everything looked good, belt not broken, teeth all in good shape (both the pulley and the belt). So I marked the belt and adjacent tooth on the pulley and had my daughter bump the engine over slowly, so I could check the entire belt. We made about three complete revolutions of very short 1/2 sec. bursts. Son of a gun, on the next bump, the doggone thing started up and my jaw hit the deck. I do not have an explanation for it! I worked the machine moderately for about an hour with frequent stops and starts with NO problems! Now I am faced with the knowledge that the service on the belt is 1600 hrs. and I am at 1684 hrs. Do I tear it down and put a new belt in or keep running it? I am concerned about the information that the Bobcat service manager gave me about the engine being an interference engine. Is it really an interference engine or was he blowing smoke? If it really is an interference engine, how long do the timing belts really last before you have problems? Oh, and by the way, Thanks to all you guys who helped me troubleshooting this problem. It has helped me greatly in learning more about my Bobcat, and about the difference in $$$$ between Bobcat parts and the exact same part at an autoparts store. Ron
 

skidsteer.ca

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Well-----------, You wont believe it!!!!!!!! I finally got my sorry rearend out back to work on the Bobcat. I took the two topmost covers off the timing belt for a looksee. Everything looked good, belt not broken, teeth all in good shape (both the pulley and the belt). So I marked the belt and adjacent tooth on the pulley and had my daughter bump the engine over slowly, so I could check the entire belt. We made about three complete revolutions of very short 1/2 sec. bursts. Son of a gun, on the next bump, the doggone thing started up and my jaw hit the deck. I do not have an explanation for it! I worked the machine moderately for about an hour with frequent stops and starts with NO problems! Now I am faced with the knowledge that the service on the belt is 1600 hrs. and I am at 1684 hrs. Do I tear it down and put a new belt in or keep running it? I am concerned about the information that the Bobcat service manager gave me about the engine being an interference engine. Is it really an interference engine or was he blowing smoke? If it really is an interference engine, how long do the timing belts really last before you have problems? Oh, and by the way, Thanks to all you guys who helped me troubleshooting this problem. It has helped me greatly in learning more about my Bobcat, and about the difference in $$$$ between Bobcat parts and the exact same part at an autoparts store. Ron
If its not too much trouble just do a visual inspection of the belt, if it free from cracks, etc, I run it for several more hour to see if the starting problem re occures, Then change the belt later.
I would think the “problem” is a minor one, you just need to pin point it.
Ken
 

Tazza

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If its not too much trouble just do a visual inspection of the belt, if it free from cracks, etc, I run it for several more hour to see if the starting problem re occures, Then change the belt later.
I would think the “problem” is a minor one, you just need to pin point it.
Ken
It sounds like a fuel problem to me..... Even the ether you fed it refused to start it, you may not have given it enough of a snort of it.
A general look at the belt won't tell you a great deal, you really need to have it off and bend it back wards and see what it looks like. Some can look fine on the outside and even the inside until you twist it back wards to stress it, then can see the cracks. I still think it should be changed soon, better safe than sorry.
As for valve interference, i believe most if not all diesel engines are. You need the valves to sit as close to the pistons as possible to generate enough compression. If they were recessed more, the compression would just not be there.
I hope the problem is not sorted out though!
 

A.G.

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I had a funny fuel problem on my 763, it would die once in while, and always at the worst time. I went after the pick up line in the tank, it was fine. On my model machine, it had a thumbscrew on the injector pump for the purpose of bleeding it. It had simply backed off a few turns due to vibration, and allowed the pump to suck air. All I had to do was prime the bulb, tighten the screw by fingers and that was it. Not sure about your machine, but your story reminded me of my simple fix, to what appeared to be baffling. A.G.
 
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