MEP-805A will crank but Won`t Start.

[ROTZINGER]

Hey Guys!
I have a MEP-805A and it cranks but wont start. One day it just stopped after a couple of hours of operation and It will turn over but wont start. there are no fault lights on and if you manually move the actuator arm it will start but you have to keep it running by moving that arm. In the instruments you can read hertz (and use it as a tachometer), alternator voltage and nothing else works. When off, if you turn the battle short on, it will not crank anymore and the undervoltage fault light will light up. I changed the governor for a new one (made sure part numbers where exact and thet everithing is conected the same, expensive AF) but the problem continues! I was told on a threat I hijacked (sorry, forum rookie here) that I should download all TM's and check the magnetic pickup BUT I cant find anything on the subject on the TM's! is the magnetic pickup maybe labeled in another way? The PDF finder cant find anything with that name...
The TM's I downloaded are this ones:
https://www.steelsoldiers.com/showt...eeded-to-work-on-the-MEP-805A-30-KW-Generator

Hope someone can help and if you hit the mexican riviera beer`s on me!

BR

 

[Zed254]

Open TM 9-6115-644-24. Search for 'magnetic pickup'.

 

[ROTZINGER]

Up date!

Open TM 9-6115-644-24. Search for 'magnetic pickup'.

Well folks, I checked the omhs, should be 800-900 and it was 0. Removed the mag pickup and simething must have hit it, Pic attached.
It seems we found the problem! Now where do I get a part number??? where can I get a new one!

Have great day!

BR

 

[ROTZINGER]

Well folks, I checked the omhs, should be 800-900 and it was 0. Removed the mag pickup and simething must have hit it, Pic attached.
It seems we found the problem! Now where do I get a part number??? where can I get a new one!

Have great day!

BR

I found on TM 9-6115-644-24Pold on page 139 item 4 this part number: 88-21061 Transducer, motional, can anyone confirm this is the right one?

thanks!

BR

 

[Zed254]

That's what I get: 4 PAOZZ PAOZZ PAOZZ 05624 88-21061 .. TRANSDUCER,MOTIONAL. Search for the part number in same document and you get an NSN number.

6695-01-367-9723. Take the NSN to PartTarget and you get multiple manufacturers and part numbers: http://www.parttarget.com/6695-01-3...ption=nsn&originalsearchtext=6695-01-367-9723

Punch the End Use item's NSN and you get: http://www.parttarget.com/6115-01-2...choption=nsn&originalsearchtext=6115012747388

MEP-804A and a whole bunch of other generators. Search on the part numbers in the first PartTarget page and you should find one.

PartTarget works on the manufacturer's part number, too.

This MAY work......https://www.ebay.com/itm/MILITARY-T...a:g:a8gAAOSwdytaxQCG:rk:2:pf:1&frcectupt=true

 

[ROTZINGER]

Hey Zed!
Thanks a lot for this info! ill do this ASAP!

BR

 

[Guyfang]

That's what I thought it would be. Try going to a truck repair shop. There is also a thread here about getting one, member 155mm put some good info in a thread on it. By and large, if a mag pickup will fit in the hole, it will work. Only hard part is getting the new one in right, so you don't repeat the whole process again. And it's NOT hard. Since you know what the proper ohm's is supposed to be, that means you read the book! The replacement procedure is about two inches further on down the page. If it dosnt make since to you, say something. We can break it down into easy steps.

 

[155mm]

804a mpu is .368" od (3/8") very common

805b mpu is .760" od

Just go to your local parts house, prefer not autozone or oreilleys, mom and pop stores are much better, they dont rely totally on computers. Take the mpu with you, ez pz.

 

[155mm]

Just in a quick 5 minute search, here is what i found for mpu.

https://smile.amazon.com/Magnetic-Sensor-Stainless-Generator-50-5000Hz/dp/B07BTRHMJJ/ref=pd_sbs_86_5/130-8156721-2378612?_encoding=UTF8&pd_rd_i=B07BTRHMJJ&pd_rd_r=8562594c-2751-11e9-a720-93fce9026ffb&pd_rd_w=6fZuB&pd_rd_wg=utSVq&pf_rd_p=588939de-d3f8-42f1-a3d8-d556eae5797d&pf_rd_r=K82BT8XGR43GVPW2CTKX&psc=1&refRID=K82BT8XGR43GVPW2CTKX



[url]https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=magnetic+pickup+sensor++3%2F8&_sacat=0&LH_TitleDesc=0&_osacat=0&_odkw=magnetic+pickup+sensor&LH_TitleDesc=0

[/URL]

 

[Guyfang]

That's what I'm talking about!!

 

[155mm]

and poof, he is gone, op hasnt logged back in since 1st day after joining/posting

 

[Zed254]

and poof, he is gone, op hasnt logged back in since 1st day after joining/posting

Sure hope he waited for your post before he bought the Ebay offering I dug up. Your prices are WAY better!!!

 

[ROTZINGER]

and poof, he is gone, op hasnt logged back in since 1st day after joining/posting

Hey! Sorry I disappeared, didn’t mean to be rude! Finding the parts and having them shipped to Mexico was a nightmare, I just received them some days ago, I didnt have any interesting updates till now...

And sadly the new part broke just like the old one did, I followed the Tms instructions to the letter and everything in the multimeter was fine, I adjusted voltage to 2.3VAC and cranked it a few extra seconds to check that everything was good. When I connected the leads back to how it should go and started it like i should, it bust to life to its normal RPM, htz started to read but this lasted just a second, then it just slowed down and barely stayed running. I checked ohms and dead crank voltage and it read 0. Took the pickup out and the tip was all messed up like the old one, luckily I ordered 2 pickups but im terrified in installing the other one and it breaking too! If I turned the engine over with the dead crank and it read voltage and ohms it means there isn’t like a fiscal thing breaking it, could it be an electrical problem that burning the pickup once the control system kicks in?

I hope someone has encountered this same issue!

Have a great day to all!

Rotzinger

 

[Guyfang]

There is a limited amount of possible reasons for this to happen. I am going to list what I think they are. Feel free to jump in here if you can think of anything else.

1. You got the reinstalling of the MPU wrong.
2. There is something else stuck in the flywheel teeth, making a high point.
3. The flywheel is out of round.
4. The flywheel is loose.

I find only number one believable. But you never know. So, try this. Take your screwed up MPU, and file or grind off the end flat. Not almost flat. Flat. Spray paint it black. Screw it in until it bottoms out. Back it off one compleat turn. Lock it down. Roll the engine over with S10. Remove the MPU. Is the end still painted? If so, repeat, but only back it off 3/4 turn. Remove it. Still painted? If so, put a good one in, and back it off 3/4 turn.roll it over, and mesure ohm's IAW the TM. What you get?

Please don't get bent out of shap. I screwed it up once or twice myself. Crap happens. Or maybe you will find the end ground off, (again) but it will be on your screwed up MPU, not a good one.

 

[ROTZINGER]

There is a limited amount of possible reasons for this to happen. I am going to list what I think they are. Feel free to jump in here if you can think of anything else.

1. You got the reinstalling of the MPU wrong.
2. There is something else stuck in the flywheel teeth, making a high point.
3. The flywheel is out of round.
4. The flywheel is loose.

I find only number one believable. But you never know. So, try this. Take your screwed up MPU, and file or grind off the end flat. Not almost flat. Flat. Spray paint it black. Screw it in until it bottoms out. Back it off one compleat turn. Lock it down. Roll the engine over with S10. Remove the MPU. Is the end still painted? If so, repeat, but only back it off 3/4 turn. Remove it. Still painted? If so, put a good one in, and back it off 3/4 turn.roll it over, and mesure ohm's IAW the TM. What you get?

Please don't get bent out of shap. I screwed it up once or twice myself. Crap happens. Or maybe you will find the end ground off, (again) but it will be on your screwed up MPU, not a good one.

Hey guyfang!
Well the instructuons on the TM are VERY clear, i hope im not dumb enough to mess them up jaja I crewed the MPU till it bottomed out (I made sure a toothe was in the middle of the hole to have a high point) backed out one full turned and then adjusted till I got 2.3V, the tightened it. Im starting to think there must be some rust or trash in the flywheele housing that might be flying around only when the engine actually speedes up and not when cranking... the strange part is it lasted so little, it waas inmediate!
Is there an "easy" way of taking the plug in the bottom of the flywheele casing of to clean the inside?

thanks and have a great night!

Rotzinger

 

[Guyfang]

Hey guyfang!
Well the instructuons on the TM are VERY clear, i hope im not dumb enough to mess them up jaja I crewed the MPU till it bottomed out (I made sure a toothe was in the middle of the hole to have a high point) backed out one full turned and then adjusted till I got 2.3V, the tightened it. Im starting to think there must be some rust or trash in the flywheele housing that might be flying around only when the engine actually speedes up and not when cranking... the strange part is it lasted so little, it waas inmediate!
Is there an "easy" way of taking the plug in the bottom of the flywheele casing of to clean the inside?

thanks and have a great night!

Rotzinger

That's something I never tried. Pulling the bottom plug. Here's another thought. Broken tooth?

And you did it by the book? Using S10 to roll the engine over while adjusting the MPU?

Try using the broken MPU like I explained, after trying to clean it out. Good practice also.

 

[155mm]

I would use the barring tool access to inspect the flywheel. That access port is on the injector pump side, opposite side of the starter.



This is the tool that goes in that hole.

 

[Guyfang]

That's something the Army didn't buy!

 

[155mm]

its worth 60 bucks in bandaids and busted knuckles

 

[ROTZINGER]

That's something I never tried. Pulling the bottom plug. Here's another thought. Broken tooth?

And you did it by the book? Using S10 to roll the engine over while adjusting the MPU?

Try using the broken MPU like I explained, after trying to clean it out. Good practice also.

Hey guys! how yall doing?
I tried what you told me guyfang and nothis hits the pickup, it just puzzels me a lot.... I going to tray this week the inspection port 155mm was talking about but I dont know if it missed me or my MEP doesent have that hole... also guyfang what us S10? ive been turning the engine with the dead crank switch above the fuel pump. I want to crank the engine in a slower way, maybe by hand, any ideas of how to do that without having to desasable the hole front of the engine?
Have a great week guys!

BR