731 running horrible - fuel issue or time to rebuild?

[DigitalFusion]

Hey All,
My old and tired 731 with the 2 cyl Deutz F2L511 isnt running right at all. She will start right up, but wont seem to 'clear out'. What I mean by that is usually she would start up and run a bit rough for a minute at low RPMs with the throttle at full, then rev up and pur as best as a 2 cyl diesel can. Now she starts right up, but never gets to full throttle and is smoking a lot. Its not dark, black smoke, its white. Every once in a while there is a loud pop from the exhaust. If it wasnt for the smoke, I'd say it was a fuel issue, either delivery or quality (water in fuel?). However, since she is smoking so much, Im kinda leaning towards a mechanical issue, namely rings on at least one of the pistons.
Im posting here to see what you guys think I should check out before I pull the engine and ship her off to Mark @ ERI. This is what I plan to go out and try after I finish my coffee and head outside:

• check all the fuel lines/connections
• toss in fresh fuel with some HEET
• compression test (how?? pull injectors?)
• ask it nicely to start running long enough for me to finish cleaning up from our house fire, then she can get a full overhaul.

Water in the fuel somehow? Fuel pump/Fuel filter?

 

[OldMachinist]

White smoke in a air cooled diesel is unburnt fuel. Causes are bad/leaking injector, injection pump timing off or very low compression.

 

[OldMachinist]

White smoke in a air cooled diesel is unburnt fuel. Causes are bad/leaking injector, injection pump timing off or very low compression.

I just thought of something else. The Deutz has a excess fuel button or lever to help with cold starting make sure the button is popping back out all the way or the the lever isn't stuck.

 

[Bobcatdan]

I just thought of something else. The Deutz has a excess fuel button or lever to help with cold starting make sure the button is popping back out all the way or the the lever isn't stuck.

I will agree with everything Old M says, I have never seen any of the machines with the 2 cylinder Deutz in my life. What I wanted to comment on is in your post you said add HEET. Do not add HEET to a diesel, that is for gas engines only. Add a diesel conditonor. I recommand to all my customers to run it. The only thing I personally see it good for is pulling water out of the system.

 

[Bobcatdan]

I will agree with everything Old M says, I have never seen any of the machines with the 2 cylinder Deutz in my life. What I wanted to comment on is in your post you said add HEET. Do not add HEET to a diesel, that is for gas engines only. Add a diesel conditonor. I recommand to all my customers to run it. The only thing I personally see it good for is pulling water out of the system.

Sorry about your house, hope everybody is ok.

 

[Tazza]

Sorry about your house, hope everybody is ok.

I too suspect an injector. I think to remove them, you need to remove the clamp that holds them down, you then need a slide hammer to shock them out. Not sure if there is another way that doesn't need a slide hammer.
They are a great engine, they start when its really cold outside and use little fuel, They just rattle a lot.

 

[DigitalFusion]

I too suspect an injector. I think to remove them, you need to remove the clamp that holds them down, you then need a slide hammer to shock them out. Not sure if there is another way that doesn't need a slide hammer.
They are a great engine, they start when its really cold outside and use little fuel, They just rattle a lot.

well I went out yesterday, and found the lift pump was leaking. I took it completely out and cleaned it. I found rust in the filter and on one of the banjo bolts. I drove all over trying to get new copper washers for it, but no hardware store or auto parts place around had anything in the right size. I ended up just cleaning them up and putting it back together with the same parts. I think the leak is fixed for now, but it didnt help my poor running issue.
I guess the next step is injector removal & compression test? Once the injectors are out, then what? Are they servicable? For the compression test, anyone know what range the numbers are supposed to be in? Sorry for all the questions... I have the service manual for this machine, but even though it didnt get burned in the fire, I cannot find where it got packed away.

 

[OldMachinist]

well I went out yesterday, and found the lift pump was leaking. I took it completely out and cleaned it. I found rust in the filter and on one of the banjo bolts. I drove all over trying to get new copper washers for it, but no hardware store or auto parts place around had anything in the right size. I ended up just cleaning them up and putting it back together with the same parts. I think the leak is fixed for now, but it didnt help my poor running issue.
I guess the next step is injector removal & compression test? Once the injectors are out, then what? Are they servicable? For the compression test, anyone know what range the numbers are supposed to be in? Sorry for all the questions... I have the service manual for this machine, but even though it didnt get burned in the fire, I cannot find where it got packed away.

Compression should be 355-575 psi and both with in 35 psi of each other.

 

[Tazza]

Compression should be 355-575 psi and both with in 35 psi of each other.

You will need a special tester for the compression. It should be in the high 300's to mid 400's from memory. The difference between cylinders should be no more than 5 or 10%.
Sadly i sold by 731 with the manuals, so i don't have the figures easily accessable.

 

[DigitalFusion]

You will need a special tester for the compression. It should be in the high 300's to mid 400's from memory. The difference between cylinders should be no more than 5 or 10%.
Sadly i sold by 731 with the manuals, so i don't have the figures easily accessable.

yesterday I messed with it some more. It looks like the rear valve cover is leaking, and its either running down the head, or the head gasket is leaking at the rear as well. The oil level wasnt horribly low, it was in the middle between the high and low mark. I noticed that it seemed to be getting worse. I had to get an old burnt AC unit moved, so I grabbed it with the loader. She would bog down and nearly die on even the smallest incline or strain, and the smoke started turning more and more black. Now she barely runs. I knew she was getting tired as winter starting has been getting more and more difficult. I dont have any idea how many actual hours are on this machine. The person I got it from replaced the hour meter, claiming there was 38XX hours on it when it was replaced. Now the hour meter is showing 175 hours. I think it might be time to just ship her off to ERI.

 

[DigitalFusion]

yesterday I messed with it some more. It looks like the rear valve cover is leaking, and its either running down the head, or the head gasket is leaking at the rear as well. The oil level wasnt horribly low, it was in the middle between the high and low mark. I noticed that it seemed to be getting worse. I had to get an old burnt AC unit moved, so I grabbed it with the loader. She would bog down and nearly die on even the smallest incline or strain, and the smoke started turning more and more black. Now she barely runs. I knew she was getting tired as winter starting has been getting more and more difficult. I dont have any idea how many actual hours are on this machine. The person I got it from replaced the hour meter, claiming there was 38XX hours on it when it was replaced. Now the hour meter is showing 175 hours. I think it might be time to just ship her off to ERI.

things arent lookin so good...
ERI isnt even sure if they can get parts, and Mark is checking into it and calling me back. Pilot engines has a listing for the F2L511, but they go through ERI. APM said the same thing as ERI and is calling me back. I called and left a message for repower specialists, we'll see what they have to say I guess.

 

[Tazza]

things arent lookin so good...
ERI isnt even sure if they can get parts, and Mark is checking into it and calling me back. Pilot engines has a listing for the F2L511, but they go through ERI. APM said the same thing as ERI and is calling me back. I called and left a message for repower specialists, we'll see what they have to say I guess.

Hopefully they can get you parts. It is a good engine, i got rid of the spare worn engine i had with my 731... There are times i wish i kept it and the manuals!

 

[DigitalFusion]

Hopefully they can get you parts. It is a good engine, i got rid of the spare worn engine i had with my 731... There are times i wish i kept it and the manuals!

ERI & APM both said they could do it. APM is about 600 cheaper, but needs 3-4 weeks to get it done and would be rebuilding my motor. ERI is 600 more, but they can do it in 2-3 weeks, have a couple of cores already in case something is wrong with mine, and seem to have a better reputation. I would love to just do this myself, and had planned to, but there is just too much chaos with insurance, mortgage company, and work on the house to deal with right now. Plus I really need to go over the rest of the machine as there are a few zerks that wont take grease on what were already oblonged pins when I bought it, and i think there is a small hydro leak somewhere. I think I will just have to bit the bullet and fork over the mucho $$$$ to have ERI do it for me as soon as we can get some money from insurance.
Another thing to mention for future searchers... Repower specialists said they would reccomend a gas conversion to a Kohler Command Pro 30HP. The complete kit was nearly 2K cheaper than the rebuild from ERI or APM. Just didnt seem to make sense to toss out what could be a great engine.

 

[Tazza]

ERI & APM both said they could do it. APM is about 600 cheaper, but needs 3-4 weeks to get it done and would be rebuilding my motor. ERI is 600 more, but they can do it in 2-3 weeks, have a couple of cores already in case something is wrong with mine, and seem to have a better reputation. I would love to just do this myself, and had planned to, but there is just too much chaos with insurance, mortgage company, and work on the house to deal with right now. Plus I really need to go over the rest of the machine as there are a few zerks that wont take grease on what were already oblonged pins when I bought it, and i think there is a small hydro leak somewhere. I think I will just have to bit the bullet and fork over the mucho $$$$ to have ERI do it for me as soon as we can get some money from insurance.
Another thing to mention for future searchers... Repower specialists said they would reccomend a gas conversion to a Kohler Command Pro 30HP. The complete kit was nearly 2K cheaper than the rebuild from ERI or APM. Just didnt seem to make sense to toss out what could be a great engine.

Personally, i'd stick with diesel. You get more out of the fuel.
Depending on your know how levels, you could probably do the work your self. It could be a few things wrong. I'd first suspect an injector or pump.
Sorry to ask, but have you changed the air filter?
As you said it started right up, it sounds like you have good compression....

 

[DigitalFusion]

Personally, i'd stick with diesel. You get more out of the fuel.
Depending on your know how levels, you could probably do the work your self. It could be a few things wrong. I'd first suspect an injector or pump.
Sorry to ask, but have you changed the air filter?
As you said it started right up, it sounds like you have good compression....

Yeah, I plan to stick with the diesel. The lower price and 2 year warranty of the Kohler is appealing, but I'd rather get the Deutz fixed. As I said, I would love to fix her myself. I have the ability to do so, but not the time or the place. Our attached garage is literally filled to the trusses on one side, and the other side has my table saw, miter saw, doors, painting supplies, and related home repair tools and items. Right before the fire, I was in the middle of a frame-up restoration of a Toyota Mini-Cruiser RV. There are two walls, the roof, and the rear wall in there in addition to anything we could salvage from the fire. I literally have to climb over things to get to my tool box, which only has half the tools in it. The other half are scattered between the house and the attached garage. We had to fire the general contractor because they kept trying to cut every corner they could. I took a leave from work for two months and am trying to get the house finished myself. I just cant fathom trying to do this work on the skid steer right now!
I havent changed the air filter, but I did pull her out and look at it. Its not 100%, but I also wouldnt say it would be causing this issue. I think it needs at the least the valve cover gaskets replaced again, possibly the covers are not square. It also might need a head gasket, and at that point I should do the head studs as well. If I am pulling the head, the pistons and rings arent that far off. Maybe I am just feeling a bit defeated with everything that is going on, but it seems like it needs so much work that its worth a full overhaul? Since I cant do it myself right now, and desperately need the skidsteer to finish up the house.. It seems worth it to me to just send her out and get her back completely redone top-to-bottom with a shiny new coat of paint.
It might just be fuel delivery, but Im not completely convinced it isnt compression as well? I suppose it cant hurt to go buy a compression tester that goes to 400 and check.

 

[Tazza]

Yeah, I plan to stick with the diesel. The lower price and 2 year warranty of the Kohler is appealing, but I'd rather get the Deutz fixed. As I said, I would love to fix her myself. I have the ability to do so, but not the time or the place. Our attached garage is literally filled to the trusses on one side, and the other side has my table saw, miter saw, doors, painting supplies, and related home repair tools and items. Right before the fire, I was in the middle of a frame-up restoration of a Toyota Mini-Cruiser RV. There are two walls, the roof, and the rear wall in there in addition to anything we could salvage from the fire. I literally have to climb over things to get to my tool box, which only has half the tools in it. The other half are scattered between the house and the attached garage. We had to fire the general contractor because they kept trying to cut every corner they could. I took a leave from work for two months and am trying to get the house finished myself. I just cant fathom trying to do this work on the skid steer right now!
I havent changed the air filter, but I did pull her out and look at it. Its not 100%, but I also wouldnt say it would be causing this issue. I think it needs at the least the valve cover gaskets replaced again, possibly the covers are not square. It also might need a head gasket, and at that point I should do the head studs as well. If I am pulling the head, the pistons and rings arent that far off. Maybe I am just feeling a bit defeated with everything that is going on, but it seems like it needs so much work that its worth a full overhaul? Since I cant do it myself right now, and desperately need the skidsteer to finish up the house.. It seems worth it to me to just send her out and get her back completely redone top-to-bottom with a shiny new coat of paint.
It might just be fuel delivery, but Im not completely convinced it isnt compression as well? I suppose it cant hurt to go buy a compression tester that goes to 400 and check.

I can understand your frustration, i really can. You need the machine to work on your house, with it not working things take longer. To fix the machine you need more time to do the work, its a loose loose situation. Then how far do you go with the engine. The barrels can be removed, so you can install new or re-conditioned ones with new pistons then your compression should be spot on.
If you got it fully done, you know it will last too. The drive system and hydraulics on the 731 are almost bullet proof. So i guess its one of thouse things to weigh up the pros and cons.
I hope you get things sorted out, you really need a win right now.

 

[DigitalFusion]

I can understand your frustration, i really can. You need the machine to work on your house, with it not working things take longer. To fix the machine you need more time to do the work, its a loose loose situation. Then how far do you go with the engine. The barrels can be removed, so you can install new or re-conditioned ones with new pistons then your compression should be spot on.
If you got it fully done, you know it will last too. The drive system and hydraulics on the 731 are almost bullet proof. So i guess its one of thouse things to weigh up the pros and cons.
I hope you get things sorted out, you really need a win right now.

Your previous post really stuck with me. I decided to dedicate a full day with no distractions to trying to get her running or at least confirm that she needed a rebuild. I dont have a compression tester that goes past 300, and my diesel mechanic friend who does have one had his baby on the 14th, so I wasnt about to bother him with asking to use it, he has bigger and better things to do! I figured I would start by doing the small things that any mechanic, shade tree or pro, would start with. This began with an overnight soaking with more cans of degreaser than I care to admit, followed by a pressure washer bath the next morning.
After blowing her dry with a leaf blower, I actually pulled the air filter out. I know I said in my other post that I had already done this, but when I thought about it I realized I had only opened the cover and looked at it. The filter wasnt horrible looking, but once I pulled it completely out I saw that she was pretty bad towards the other end. I replaced it with a brand new Wix/Napa gold. There was also a lot of debris way back at the end, outside the filter that I somehow missed the last time I checked. I then drained the fuel tank completely and replaced the fuel with fresh summer blend along with some diesel 911. I drained the fuel lines and pumps and then replaced the fuel filter with another Wix/Napa Gold primed with some diesel 911. I then drained the fuel tank and supply lines completely and bled the lines. The excess fuel solenoid wasnt working, and Im not convinced it wasnt playing havoc with things by slightly depressing the push pin, so I completely removed it from the engine. While I was doing all this I went ahead and replaced the alternator/fan belt and adjusted the tension. I know this wasnt really related to the issues I am having, but it needed to be done.
The starter has been slowly going out on me since last winter, spinning but not engauging the flywheel on occation. During the course of all these running issues it keeps getting worse, and will now only engage 1 out of 10-15 times! I put the battery charger on her and just kept trying just to see how she ran. When she finally did engage and fire.. man... she purs like new again! I cant explain how silly I feel for not going through the obvious and simple steps and just jumping to the conclusion that it needs an overhaul. There still is a tiny oil leak at the head, I need to get a new starter or have this rebuilt, the damned alternator bolt broke off, and I know she cant be at 100% compression, but at least I bought some time!
Thanks to everyone who posted here, and thanks to you Tazza for asking the obvious question about the air filter that help slap me out of my stupor and realize that I had pretty much skipped all the steps and jumped to the overhaul solution!

 

[DigitalFusion]

Your previous post really stuck with me. I decided to dedicate a full day with no distractions to trying to get her running or at least confirm that she needed a rebuild. I dont have a compression tester that goes past 300, and my diesel mechanic friend who does have one had his baby on the 14th, so I wasnt about to bother him with asking to use it, he has bigger and better things to do! I figured I would start by doing the small things that any mechanic, shade tree or pro, would start with. This began with an overnight soaking with more cans of degreaser than I care to admit, followed by a pressure washer bath the next morning.
After blowing her dry with a leaf blower, I actually pulled the air filter out. I know I said in my other post that I had already done this, but when I thought about it I realized I had only opened the cover and looked at it. The filter wasnt horrible looking, but once I pulled it completely out I saw that she was pretty bad towards the other end. I replaced it with a brand new Wix/Napa gold. There was also a lot of debris way back at the end, outside the filter that I somehow missed the last time I checked. I then drained the fuel tank completely and replaced the fuel with fresh summer blend along with some diesel 911. I drained the fuel lines and pumps and then replaced the fuel filter with another Wix/Napa Gold primed with some diesel 911. I then drained the fuel tank and supply lines completely and bled the lines. The excess fuel solenoid wasnt working, and Im not convinced it wasnt playing havoc with things by slightly depressing the push pin, so I completely removed it from the engine. While I was doing all this I went ahead and replaced the alternator/fan belt and adjusted the tension. I know this wasnt really related to the issues I am having, but it needed to be done.
The starter has been slowly going out on me since last winter, spinning but not engauging the flywheel on occation. During the course of all these running issues it keeps getting worse, and will now only engage 1 out of 10-15 times! I put the battery charger on her and just kept trying just to see how she ran. When she finally did engage and fire.. man... she purs like new again! I cant explain how silly I feel for not going through the obvious and simple steps and just jumping to the conclusion that it needs an overhaul. There still is a tiny oil leak at the head, I need to get a new starter or have this rebuilt, the damned alternator bolt broke off, and I know she cant be at 100% compression, but at least I bought some time!
Thanks to everyone who posted here, and thanks to you Tazza for asking the obvious question about the air filter that help slap me out of my stupor and realize that I had pretty much skipped all the steps and jumped to the overhaul solution!

I should add, for future searchers, or myself when the day comes to rebuild:

• Repower-engine swap: repowerspecialists.com was $2685.00 for a gasoline Kohler Command Pro 30 HP conversion with everything needed to retro fit. This included shipping and a 2 year warranty on the engine from Kohler.
• Rebuild from APM: Rebuilding from APM was $3016, plus 400 for round trip shipping. If you need a lift gate its and additional $50. Turn around time was about 3 weeks, and included a 6 month/1000 hour warranty.
• Rebuild from ERI: Rebuilding from ERI was $4115 which included round trip shipping. Turn around time was about 2 weeks, and included a 6 month/unlimited hours warranty.

 

[jerry]

I should add, for future searchers, or myself when the day comes to rebuild:

Repower-engine swap: repowerspecialists.com was $2685.00 for a gasoline Kohler Command Pro 30 HP conversion with everything needed to retro fit. This included shipping and a 2 year warranty on the engine from Kohler.
Rebuild from APM: Rebuilding from APM was $3016, plus 400 for round trip shipping. If you need a lift gate its and additional $50. Turn around time was about 3 weeks, and included a 6 month/1000 hour warranty.
Rebuild from ERI: Rebuilding from ERI was $4115 which included round trip shipping. Turn around time was about 2 weeks, and included a 6 month/unlimited hours warranty.

good to hear its cured, now you can pull the starter and chances are all you need to do is clean and lube or replace the drive which should not cost much.