Diesel idiot with G5200 fuel problem !! Help ?

[bevis]

Ok so i buy this g5200 that the guy says just needs some love but mows great and runs great. So, i give him $800 for it and start giving it love.
Here is what i have done
sandblast all wheels and repaint Kub original color
replace both front tires and all 4 front wheel bearings
replace all filters
change oil and hydro fluid / clean sump screen
replace crank to hydro coupling after it exploded on me
fab new shafts and buy new rollers for front of deck
buy hour meter / screens / rad screen / all seat bushings
and other little things

So, i take it , after a month of screwing with it in the garage giving it love and
it starts blowing black smoke under load and overheats.

SO, i force water through the block by removing stat ( which is bad - stuck almost closed ) and plugging everything off so I'm forcing water into the water neck and the only place it can get out is through the block drain ( which is also trashed and I'm looking for the thread pattern so i can just put a plug in it ).

Then i force water through the rad by closing everything off so the only place water can go is through the the top of rad. Filled with plain water and watched inside the rad to make sure i could see water moving. It is , so i assume the pump is working.

Put it back together without the stat for testing. Start mowing and it seems ok but then starts blowing black smoke and bogging down after going about 100 feet. Insert lots of cuss words !!!!!!!
I pull it back to the garage and shoot the water neck / rad / block / water pump with infrared heat gun. No readings over 180. I think I'm all good but clearly still have a problem. So i start it up with no load. Idles perfect. Raise RPMS to almost max. It blows out black smoke then smooths out. But wait, it starts to bog back down and then blow black smoke again. Then it recovers and runs smooth and then repeats bogging and black smoke . Rinse and repeat many times. Throw tools on cart and say screw it I'm done with you , your going to have to find a new home because i don't know how to work on this damn diesel.

So now I'm looking at air intake problems but i have just put in a new filter.
Now I'm starting to think i have a fuel problem but I'm clueless about diesel motors. This aint no small or big block chevy. Im about as ignorant about diesel motors as it gets but i do know i have a fuel or air delivery problem. I have not run a combustion gas test on the rad nor a compression test yet. I will if i have too but i really don't think thats where the problem is. There is no water in the oil nor oil in the water. After reading what the function of a glow plug is, i don't think thats the problem either . I preheat the GP's and it fires and idles perfect every time. SO here i am being completly lost as to how to troubleshoot this issue. It has new fuel in it and all the filters are new. I suspect the fuel pump is working just fine as its certainly getting fuel. Do i need to clean injectors ? How in the world do you go about that ? As i said I'm clueless about diesel. I have been working on naturally aspirated and forced induction engines for 45 years but this is way outside my knowledge base. So I'm almost ready to admit defeat and part the damn thing out.

Any troubleshooting tips and or direction would be greatly appreciated.

 

[CountryBumkin]

The typical causes of Black smoke is:
1) Engine Overload
2) Fuel: poor quality or clogged filter
3) Air: clogged air filter or collapsed
4) bad injector nozzle

The easiest things to do first are to replace the air filter and the fuel filter(which you did). Is the air filter you used OEM? Try running it without the filter.

However, from your description (black smoke in neutral) I would focus on either the injectors or a problem with the hyd pump/system (causing excessive engine load at high rpm).

You mentioned that the crank-hydro coupler blew up. Maybe it did that because there is a pump problem putting too much load on the coupler. Can you remove this coupler again and see if the smoke problem goes away?

If it still smokes after coupler removed, I would focus on having injectors tested/cleaned (this means removing them and taking to diesel shop).

 

[bevis]

The typical causes of Black smoke is:
1) Engine Overload
2) Fuel: poor quality or clogged filter
3) Air: clogged air filter or collapsed
4) bad injector nozzle

The easiest things to do first are to replace the air filter and the fuel filter(which you did). Is the air filter you used OEM? Try running it without the filter.

However, from your description (black smoke in neutral) I would focus on either the injectors or a problem with the hyd pump/system (causing excessive engine load at high rpm).

You mentioned that the crank-hydro coupler blew up. Maybe it did that because there is a pump problem putting too much load on the coupler. Can you remove this coupler again and see if the smoke problem goes away?

If it still smokes after coupler removed, I would focus on having injectors tested/cleaned (this means removing them and taking to diesel shop).

i can remove the new OEM filter and see if it improves.
I can unhook the coupler ( BIG PITA and a lot of cursing )
Im tired of throwing money at it and if its injectors, i would just replace all 3 of them ( lol like i even know how to get them out ) . Any idea on costs if injectors need replaced ?

 

[bevis]

also it appears that you cannot buy the pump but you have to buy the entire transaxle.
and at 2K for the transaxle, ill part the thing out

 

[rentthis]

You mentioned changing the fuel filter. Have you checked for a second fuel filter? I once had a G machine and cussed it for days until I found the other filter. It was closer to the tank and stopped up.

 

[bevis]

You mentioned changing the fuel filter. Have you checked for a second fuel filter? I once had a G machine and cussed it for days until I found the other filter. It was closer to the tank and stopped up.

Yup, thats the first one i changed. I also changed the canister one and bled the system. cleaned the hydro sump screen and new O-rings on the banjo fitting. changed the oil and filter. changed the spin on hydro filter. All the filters and fluids were the first things i did.

 

[bevis]

i read a thread on here somewhere that was talking about changing injector timing. I have no idea if someone has messed with that in the past or not. I also suspect that no chemical that you put in the fuel will be aggressive enough to address the injectors. don't you have to be real careful with removing the injectors ? i thought i saw a vid where a guy yanked an injector and a small part fell off that was almost impossible for him to get back on. I wish i had more experience on diesel's. Maybe its time to put the 350 i have on a motor stand in the damn thing.

 

[North Idaho Wolfman]

I just did a quick read as I'm headed out the door, sounds like valve issue, check the valves, pull the valve cover and make user the are adjusted properly.
If you don't have the specks I can get the a little later for you.

 

[bevis]

I just did a quick read as I'm headed out the door, sounds like valve issue, check the valves, pull the valve cover and make user the are adjusted properly.
If you don't have the specks I can get the a little later for you.

please get the specs and i'll check the valve lash. i have no idea what it should be or how to go about it.
thanks

 

[CountryBumkin]

i read a thread on here somewhere that was talking about changing injector timing. I have no idea if someone has messed with that in the past or not. I also suspect that no chemical that you put in the fuel will be aggressive enough to address the injectors. don't you have to be real careful with removing the injectors ? i thought i saw a vid where a guy yanked an injector and a small part fell off that was almost impossible for him to get back on. I wish i had more experience on diesel's. Maybe its time to put the 350 i have on a motor stand in the damn thing.

Since you said the engine starts nicely and idles fine, so I don't think your engine compression is low. If it was low, I think you would have a harder time starting engine.

If injection pump timing was retarded too much that could cause black smoke but would also result in hard starting - which you don't report. You said the engine runs normally (you are cutting grass) for a little while then problem starts. So it seems like the problem is heat related (something is heating up and changing - like valve clearances as Wolfman said, or maybe hyd pump is heating up and loading engine).

Generally speaking, injection pump timing changes affect the engine like this:

advanced too much:
noise (diesel clatter)
white smoke (or grey) especially when cold
missing under certain load conditions
runs hotter
slow down shudder

retarded too much:
black smoke
hard to start
missing under certain load conditions
slow down shudder

 

[bevis]

Since you said the engine starts nicely and idles fine, so I don't think your engine compression is low. If it was low, I think you would have a harder time starting engine.

If injection pump timing was retarded too much that could cause black smoke but would also result in hard starting - which you don't report. You said the engine runs normally (you are cutting grass) for a little while then problem starts. So it seems like the problem is heat related (something is heating up and changing - like valve clearances as Wolfman said, or maybe hyd pump is heating up and loading engine).

Generally speaking, injection pump timing changes affect the engine like this:

advanced too much:
noise (diesel clatter)
white smoke (or grey) especially when cold
missing under certain load conditions
runs hotter
slow down shudder

retarded too much:
black smoke
hard to start
missing under certain load conditions
slow down shudder

just for my education, how is the timing changed, advance or retard ?
Also I'm told that its just a coincidence but all this all started right after i cleaned the
sump screen. Right after i put it back in with new Orings, i started the motor to check for leaks
and thats when the coupling exploded . Seems like things have went down hill as far as the motor
is concerned since that event.

 

[bevis]

also after looking at it more this morning, it appears that the fuel system is open loop and not a dead head system. i see what appears to be a return line to the tank. i think i should make sure that its not obstructed. Is that what I'm seeing ? An open loop system ?

 

[Daren Todd]

I don't think your timing jumped or got messed with. What your describing seems like too much fuel as stated. A quick easy way to tell if its over fueling is to give the exhaust a sniff test. If it smells like unburned diesel and burns your eyes if its in an enclosed space, thats a pretty good sign of too much fuel

A couple things could cause it. One is a bad injector or injectors. Another cause is if the ports on top of the injection pump are loose. It's where the fuel injection lines tie into the injection pump.

To check to see if the ports are loose, you will need two wrenchs. One to fit the port, the other to loosen the injection line. First loosen the injection line, using the other wrench to hold the port in place. Then check the port to see if it's tight. Injection line doesn't need to be removed to tighten it up, just loose to allow the port to turn.

This happens quite frequently if someone loosens the injector lines at the injection pump with out putting a back up wrench on the port to keep that portion tight

Inside the port is spring loaded. Loose it will allow fuel to free flow through the injection pump, and you won't get the correct pressure and amount of fuel for the spurt in the injector. Tight, you should get a good spurt if you loosen the injection line at the injector.

 

[bevis]

I don't think your timing jumped or got messed with. What your describing seems like too much fuel as stated. A quick easy way to tell if its over fueling is to give the exhaust a sniff test. If it smells like unburned diesel and burns your eyes if its in an enclosed space, thats a pretty good sign of too much fuel

A couple things could cause it. One is a bad injector or injectors. Another cause is if the ports on top of the injection pump are loose. It's where the fuel injection lines tie into the injection pump.

To check to see if the ports are loose, you will need two wrenchs. One to fit the port, the other to loosen the injection line. First loosen the injection line, using the other wrench to hold the port in place. Then check the port to see if it's tight. Injection line doesn't need to be removed to tighten it up, just loose to allow the port to turn.

This happens quite frequently if someone loosens the injector lines at the injection pump with out putting a back up wrench on the port to keep that portion tight

Inside the port is spring loaded. Loose it will allow fuel to free flow through the injection pump, and you won't get the correct pressure and amount of fuel for the spurt in the injector. Tight, you should get a good spurt if you loosen the injection line at the injector.

I will see if the ports are tight, thats an easy enough test. So issue that the next step, if the ports are tight, would be replace all 3 injectors ? Is there any special procedures for changing the injectors or are they just like a car injector ?

 

[D2Cat]

For injector service I would not just go out and purchase new injectors. Take what you have to a diesel injection service shop. They can test for pop off pressure and spray pattern. Might get an idea of price before hand, but I take injectors to a shop and watch them do the test. (I have an appointment. They know I'm coming, and what for).

This shop has tested 4 sets of injectors for me over the last couple of years. Needed one set rebuilt. They hever charge me for the testing.

 

[bevis]

For injector service I would not just go out and purchase new injectors. Take what you have to a diesel injection service shop. They can test for pop off pressure and spray pattern. Might get an idea of price before hand, but I take injectors to a shop and watch them do the test. (I have an appointment. They know I'm coming, and what for).

This shop has tested 4 sets of injectors for me over the last couple of years. Needed one set rebuilt. They hever charge me for the testing.

is there any special procedure for pulling the injectors ?

 

[North Idaho Wolfman]

Before you go getting into disassembling things, replacing parts and running the risk of breaking expensive parts, that probably don't need it get the WSM.
P/N 97897-11030
http://www.colemanequip.com/Parts_Detail.asp?partID=19460

Have you tried loosening the fuel tank cap when it loads up?
Could be a simple case of plugged vent in the cap.

The injection system timing is only changed by adding or removing shims under the injection pump.
If the pump has never been out (look at the paint), it's not out of time.
If it has been out get the WSM and it will tell you how to put it back in time.

 

[Russell King]

just for my education, how is the timing changed, advance or retard ?
Also I'm told that its just a coincidence but all this all started right after i cleaned the
sump screen. Right after i put it back in with new Orings, i started the motor to check for leaks
and thats when the coupling exploded . Seems like things have went down hill as far as the motor
is concerned since that event.

Timing is changed by shims between injector pump and block mounting surface. I don't recall if adding shims retards or advances timing.

To eliminate coincidental problem take shaft apart again, may be difficult but then you will isolate or eliminate that system as a trouble spot.


Sent from my iPad using Tapatalk

 

[mrmr56]

It is much easier to unbolt the drive shaft from the hydro pump and just slip the drive shaft rearwards out of the spline. No need to mess with the bolts on the rubber coupler.

 

[bevis]

It is much easier to unbolt the drive shaft from the hydro pump and just slip the drive shaft rearwards out of the spline. No need to mess with the bolts on the rubber coupler.

If i remember correctly, when you get the 2 bolts out of the driveshaft flange, there is not enough room to clear the fiberglass flange on the front of the pump to pull the shaft out of the rubber coupler in the back of the crank.