Gehl RS6-42 wont run

[MotorHeadz]

HELP!!!!!! I have a Gehl RS6-42 with a John Deere 4045tf275 enginethat was running and dying and cranked back up but would have low power.This was a new customer at the time and he insisted on changing the injection pump because somebody told him it needed a new one.Anyway, replaced injection pump and unit has not run since.I checked all the electrical and pulled injector nozzles and had tested,Checked and rechecked timing and all checked ok. Condemned and replaced injection pump again, replaced all nozzles and unit still cranks but will not start. Checked compression found one cylinder under 200 psi and one around 50 Psi looked so decided to infram!e unit. Now unit has new liners and pistons,rod and main bearings, reworked head,, new injector nozzles, new transfer pump, new supply and return lines from tank to engine, and still cranks but wont start and run. I have also replaced the ECM and taken to RDO and had programmed. I have had 3 other guys look at it and everybody says " it should crank and run". Have had John Deere service Tech come scan it and go thru it checked and rechecked timing, installed a third injection pump,Pulled front cover to check gear train replaced Injector Nozzles again replaced starteretc. etc. etc. so, Basically everything engine wise is new except the block ,all fuses and electrical seem to check ok but unit still cranks but wont start and run , can get to run on ether but wont pickup fuel and run on its own. ALL iDEAS ARE APPRECIATED , IjUST WANT TO GET THIS THING FINISHED!

 

[Knepptune]

We have a lull with that same engine, believe it's an 05. If it is at all low on voltage it absolutely no matter what will not start. If you don't plug that thing in when its below 40* it just isn't gonna start. We replaced injection pump and have chased wires all over. The thing is once it starts its a fantastic running engine.

 

[MotorHeadz]

i have tried plugging in and letting it set for a couple hours no change. i spent half a day the other day and it was almost 80 degrees, no change. i have replaced the battery and always have my service truck and sometimes my jump box too hooked up when trying to crank it. it does seem to drain the battery pretty quick. I believe this is an 05 also. 'i'm wondering if maybe i'm missing something in the wiring

 

[Newfiedan]

check for voltage drops while cranking, also the gehl system may have an external shut down like a secondary oil pressure switch that kills off the john deere ecm. Usually external ones are going to end up being temperature and oil pressure. Also as a thought have you pulled the pump off the engine and tried running it without it attached, the reason I ask is that I have seen them try to start under a hydraulic load and it will crank till the cows come home but never start, that is something a jd tech will never see on a laptop. It does not take a lot of load to stop it from starting. I had the same issue with a few gehls over the years. There may be a declutch switch on the dash for the transmission/pump, I do believe that it was under the steering wheel right side of the dash on the gehls.

 

[deeretech89]

i too am having the same issue the tech manual says that its the red wire from the fuel cut off fuse and ignition relay.

 

[MotorHeadz]

well at this point i'll try just about anything were is this fuse and relay located? as nothing is marked on this machine.

 

[deeretech89]

its under the view cover plate in the cab on your right above the joysticks were the boom bible is.

 

[Reed]

I didn't see anything about fuel in any post maybe I missed it. Do you have fuel to injectors

T. Reed
Field service tech

 

[jatspic05]

I had one have the same issue. One cause for voltage drop is, there is a brake module that shorts out. Sitting in the seat, remove the lower cover to the right, there should be a black module there, check to see if it has a bulging bubble on the side. If it does this could be part of the problem. Also check the ground cable or move the connection point on the engine side to another location. JD are very sensitive to voltage in my experience. Anyway once I replaced the brake module and relocated the battery cable the unit started and ran fine. hope this is helpful. Good luck.

 

[Jason03]

Where does the red wire go after the view box? mines just dangling. Thanks

 

[speedypete]

did you ever find problem im having same issue.
thx

 

[Bls repair]

Are you getting fuel out of supply pump,out of injector pump

 

[speedypete]

Yes

 

[Bls repair]

Good solid flow out of supply pump

 

[jatspic05]

Also check the positive battery cable, see if it has rubbed through somewhere and grounding out. I had one that had this issue, someone ran the positive cable over the exhaust pipe and melted the cover.

 

[1rossolsen7]

Hey guys,

New to the forum, but glad to be here. Anyway, I had the same problem you were having with the Gehl RS8-44 with the Deere 4045 up here in Sitka, AK. Cranks til the cows come home, no smoke, no start. The owner of the machine called our shop and asked for some assistance, so we went to check it out. When I first arrived (a month ago now), we had electrical issues in the cab, fuse block area. We had a blown relay, and when we replaced that, we were popping the fuse for the ignition switch. Finally got that issue straight (who ever cobbled the wiring together in this before us... what a nightmare). Anyway, once we resolved that issue we were able to connect to the JD Service Advisor and pull up some codes. We were getting codes for the analog throttle being out of range. We took the TPS off of the throttle pedal, cleaned it up, and clocked it so that we were getting the proper voltage readings on the service advisor. Codes had cleared, but we still had all crank and no run.

Now when I tell you we had issue after issue, I mean it. We had incorrect voltage readings on just about everything we tested for the first week or so, the service advisor was hit or miss on every window we tried to open. Everything pointed to the ECU. We replaced it with a "known-good" ECU like Deere says to. Finally got the darn thing able to open up some trim pages, and we tried shutting off some of the "shutdowns" programmed into the ECU. Still didn't run.

Now, we're communicating with some guys back in Seattle about different things. We had chased wires, fuses, fuel lines, filters, everything you guys have described. They sent us up a new Standyne DE-10 pump, and we timed it AS THE BOOK said, and guess what, it still didn't run.

Somewhere along the line, we went to pump up the transfer pump by hand, and it was just leaking fuel out of the weep hole, suggesting the diaphragm was bad. So we replaced that. Still no fire.

So today, we started grabbing at straws. Pulled valve cover, CHECKED VALVES AT TDC and put the pin in the flywheel like Deere asked. Rotated engine 360* to get the rest of the valves. Everything checked out alright. Went to crank the engine just for giggles, and when we went back to look over some more stuff, we saw 1/8" of clearance under both #1 cylinder valves... what the heck? We used the timing pin just like they asked! But wait... does that fricken pin go into the flywheel at more than one spot? SURE DOES. Ours went in, in 8 different positions along a full rotation of the crank. YOU HAVE TO BE KIDDING ME!

What does that mean? We pulled the injector from the #1 cylinder and used a small piece of gas welding rod to really see when #1 was at TDC. Sure enough, way off on the valves. So we went to re-adjust. INT and EXH on #1, INT on #2, and EXH on #3 (I believe that's the right order off the top of my head.) But what that also means is that

IF THE TIMING PIN GOES IN THE FLYWHEEL, IT DOES NOT MEAN THAT THE ENGINE IS ON THE RIGHT STROKE!!! WHICH IN TURN, CAN ALTER THE TIMING ON THE INJECTION PUMP!

We pulled out the plug for the timing pin in the injection pump and sure enough, it was out of time. We pulled the gear off, took the pump out (meanwhile, the flywheel timing pin is still in the engine), and put the timing pin in the injection pump. Put everything back in torqued the gear, hooked the lines back up, and cranked but still wouldn't start. We cracked the lines loose at the injectors to bleed the air out, got fuel at all four lines, tightened them and WALLAH!!! Fire in the hole!

I'm sorry for the novel, but after hearing about so many people fight with this miserable collaboration of parts and manufacturer's, I just hoped that maybe this would help someone out. The moral of the story is, make sure that #1 is at the top of its stroke and the valves are loose before you assume the timing pin in the flywheel is in the right position, and then pin the pump. I have no idea why there were 8 holes in the flywheel, and I would hope that if they were from where they drilled for balancing, that they wouldn't fall in the same groove as the hole for the timing pin. Either way, it sure jerked us around a lot, 3 weeks of chasing ghosts and we finally got an answer.

Best of luck to you guys and if there's anything I can help you with, let me know and I'll do my best.

 

[Mete Lift]

thx buddy

 

[Lchbuilders]

Hey I hate to bring up an old thread but did you ever figure out the issue? Have a rs6-42 that is doing the same thing and am desperate to get it fixed

 

[Will86]

Hey I hate to bring up an old thread but did you ever figure out the issue? Have a rs6-42 that is doing the same thing and am desperate to get it fixed

Did you get your machine going?

 

[Lchbuilders]

Yes I did, called a john deere dealer because it has the 4045t engine. Computer had some goofy codes and somehow it threw the external shutoff code even though my lift does not have an external shutoff. Tech played with the computer and she runs like a champ. He said if it happens again it will need a new ecu thingy but 3 weeks now and all is good