MEP-831a no crank and oil pressure light is on

[Cord]

Was using my MEP-831a earlier today. Started and ran fine. Shut it down because the task was complete. When I went to start, it wouldn't crank. I only get a loud click from the throttle actuator. Acting like the batteries are dead, but I don't believe they are. The machine was only shut off for an hour, plus it has the solar battery charger. I pull started it ok, but noticed the oil pressure light stayed on and it wasn't running at full speed. I flip the switch to off and the engine didn't shut down. I flipped the switch back to on and the engine immediately shut down. Probably because of the low oil pressure. Check the oil and it was full. I restarted the engine by pulling it and this time overrode the oil pressure switch with the battle short toggle. Unit ran fine and picked up a load normally. Ran for 40 minutes until I shut it down.

The obvious solution would be to blame the oil pressure sending unit, but that doesn't explain the no crank problem. Somehow I think the two issues are related, but I don't know how. Anybody ever see this issue before? Ideas on what to start checking?

 

[Guyfang]

Did you reset the fault indicator before starting it again?

 

[Cord]

Ok, I'll bite... How do I reset it?

 

[Cord]

Too obvious. I hit the button and it cleared the oil pressure light. I then shut the unit down and tried to restart it. No crank. I manually restarted and now the fault reset button doesn't clear the oil pressure light.

 

[kloppk]

Are you following the procedure on the data plate above the pull start cord when doing a manual start?
After doing the pull start you need to also momentarily toggle S1 to Start position to clear the OP fault.

For the "no crank" problem there is a section in the -13 TM to troubleshoot that.

 

[Cord]

Is the "S1 Toggle" the start-run-stop switch? If so, it does nothing to clear the fault.

 

[Zed254]

May need to do some reading.......https://www.steelsoldiers.com/showthread.php?155865-Manuals-for-the-MEP-831A

 

[Dewie38]

When you rope start the set make sure the start switch is in the run position, after you manually start the set, momentarily place the start switch to stop position then to run.

 

[Cord]

Well, I’m back up north at my cabin and sure enough I forgot my multimeter at Home. I installed a mechanical oil pressure gauge and it reads 15lbs. Anybody know what spec is? I then disconnected the one terminal off the oil pressure switch and now the light is off. I’ll need to check the switch to make sure it’s opening.

The no crank problem still remains, but the unit pull starts fine.

I had the unit running when when I tried to start a trim saw and the unit cut out. I restarted it and saw the voltage go off the scale high and then drop to zero followed by an over volt light. Sadly, the TM is silent on this issue.

At at the moment, I have three electrical faults within a couple hours of run time. I’ll go in town to buy a multimeter and start checking terminals, but I suspect there some electrical component that is central to all these faults.

 

[kloppk]

I installed a mechanical oil pressure gauge and it reads 15lbs. Anybody know what spec is?

You should see about 100 psi at startup. Will drop to about 85 PSI when warmed up. 15 is way too low.

The no crank problem still remains, but the unit pull starts fine.

Have you followed the TM's No Crank procedure? It walks thru testing each of the items in the crank circuit.

 

[mcii]

You can later throw cold water on my response, but at one point 2 years ago I had 5 of these sets, and without fail never could get more than 3 to run at the same time, and never the same 3. always one roving problem after another, and really never a solid fix, just unexplained the issue would go away. and all be well for a time period.
I forget the final tipping point, but I ordered 5 of the Kurt Klopp new control boards, to this date I have yet to have any problems with starting or reliability or repeatability, confidently I sold off 3 of the sets and the new owner has only said how well and reliable the sets have been in his application.
I'm not a paid or compensated person for Kurt's boards. But I am a very pleased user owner and I tell all new purchasers the single best thing to do is immediately change the original control board, while it seems to not make sense, these sets sell for 250.00 at this location I found them and to then spend another 125, sorta cuts against the "good deal" aspect, but its not a good deal if it is not reliable and functional set. your mileage will vary but my experience is what I go by .. best: mac/mc

 

[robson1015]

You can later throw cold water on my response, but at one point 2 years ago I had 5 of these sets, and without fail never could get more than 3 to run at the same time, and never the same 3. always one roving problem after another, and really never a solid fix, just unexplained the issue would go away. and all be well for a time period.
I forget the final tipping point, but I ordered 5 of the Kurt Klopp new control boards, to this date I have yet to have any problems with starting or reliability or repeatability, confidently I sold off 3 of the sets and the new owner has only said how well and reliable the sets have been in his application.
I'm not a paid or compensated person for Kurt's boards. But I am a very pleased user owner and I tell all new purchasers the single best thing to do is immediately change the original control board, while it seems to not make sense, these sets sell for 250.00 at this location I found them and to then spend another 125, sorta cuts against the "good deal" aspect, but its not a good deal if it is not reliable and functional set. your mileage will vary but my experience is what I go by .. best: mac/mc

$ 250 per unit ???? Sounds too good to be true.

 

[Cord]

Out of curiosity I reached out to Kurt to learn more about his circuit boards. He responded quickly and volunteered to help diagnose the problem. His instructions went well beyond the TM and were so well detailed that I posted them below. I went through every step while the wife and I referred to the wiring diagrams that are stored inside of the lid. Got to the point that my starting problem was due to a bad starter. Pulled the starter and tested it and it does appear to be bad.

I then pull pull started the engine and cleared the oil pressure light. Cycled the start switch and saw voltage. The oil pressure light was due to me forgetting to clear it. But the high voltage issue that appeared after the unit tripped off from the overload wasn’t me. Whatever was causing that fault went away.

Regardless, once I get the starter replaced, I’ll be ordering a controller from Kurt. Thanks!

The TM attempts to have the operator do as many tests with no power applied to the circuit to minimize the possibility or shorting something out while troubleshooting. Unfortunately it doesn't provide the best way to really troubleshoot some problems.


The TM directions are "OK" but here is how I'd suggest you troubleshoot the No Crank issue.
1) Set Battle Short to OFF
2) Connect your meters Negative lead to the engine block.
3) Set the meter to DC Volts to a range were it can read 24 volts DC


For each of the following test perform the voltage measurement with S1 in the START position and checking for ~24 Volts DC at each of the following points in the following order.
4) S1-1
5) TB5-11
6) TB5-9
7) K2-X1 One of the two small terminals on K2. It has wire 10A18 connected to it.


For each of the following test perform the voltage measurement with S1 in the START position and checking for ~0 Volts DC at each of the following points in the following order.

K2-X2 The other small terminal on K2. It has wire 11B18 connected to it.

9) K15-1
10) K15-9
11) S7-1
12) S7-2


For each of the following test perform the voltage measurement with S1 in the START position and checking for ~24 Volts DC at each of the following points in the following order.
13) K2-A1 It's one of the large terminals on K2 and it has 3 wire going to it.
14) K2-A2 It's the other large terminal of K2 with only 1 wire going to it.
15) B1 (Starter Motor) where the small push on wire terminal attaches to the starter. Leave the wire connected and touch the meter probe to part of the small wire terminal lug on the starter motor.
16) The large terminal on the starter motor where the two large cables with red shrink tubing on them connected to it. Touch the meter probe to the end of the stud when making the measurement and not the wire lugs.
17) On the starter there is a black rubber cap with a strip on metal leading out from under to it. Touch your mete probe to the metal strip and check for power.


If all the above tests "pass" then I suspect you have a bad starter motor.
However I suspect one of the above tests will "fail" leading us to the No Crank issue.


​

 

[Ray70]

Hello Cord, I have 831A that was once doing similar things. It would randomly shut off after a minute or 2 and I would get over voltage and obviously low oil faults when it died. I also installed one of Kurt's controllers and it has been good ever since. A word of advise, when you install the controller, also take a few minutes ( if you haven't already ) and follow the speed control linkage adjustment procedure in the TM. If you are out of adjustment or the jam nuts aren't tight and the linkage adjustment is moving around due to the vibration, you will end up with all sorts of problems.... ask me how I know...
I wouldn't worry about your over voltage fault until you get the new controller installed and get it running correctly, chances are it will go away on its own once the speed controller is working correctly.

 

[Cord]

Anybody have a source for a used starter? My local rebuilder got a starter on, but it’s 12v and he’s adamant they don’t make a 24v version.

 

[dav5]

I bought a spare 803a 24v starter on Ebay and brought it in to my local rebuild shop [who I have had very good experiences with] to get it checked out and he basically said the same thing. He told me he couldn't tell if it was 12 or 24v but that a 12v on a 24v system would work just fine. He did say if I wanted to rebuild a non working starter he could order a 24v solenoid for it. I would be interested in hearing about any other experiences any one else has had.