Fixing up my MEP-803A"

[Light in the Dark]

The orientation of the jumper matters too.

 

[majoday]

Look at the schematic. Pins 1&7,

View attachment 864678

I see. I ran the schematic for CR$. 1 & 7 . It looks like 2,4,6,&8 are ganged. How simple is clarity. I will review this. My new switch is on the way.

 

[majoday]

I see. I ran the schematic for CR$. 1 & 7 . It looks like 2,4,6,&8 are ganged. How simple is clarity. I will review this. My new switch is on the way.

Well, it nhas been a while, a long while, since I read a schematic. So..., I have had to brush up on my skill and dust off the recesses of my memory bank (AF Ground Radio Repairman 30354, 66-77). Thank you all for the support in getting the unit going. I am now awaiting the switch.

 

[majoday]

Installed the new Electroswitch. Checked out the wiring to be sure of an accurate attachment to the switch. Learned positions of TBs , Jacks, Relays busu with fence building. Project on hold. Spent most of the day on a scheduled CAP (Civil Air Patrol) mission; Mission Chaplain, Mission Scanner.

 

[majoday]

I agree, verify barb distance from push rod tubes is about equal first.
When taking the temps it is very difficult to get accurate measurements because the fan tends to cool the front of the engine much faster than the back cylinder, which is also what your temp readings are showing.
Try blocking the airflow around the exhaust side of engine and take the temp at the underside of the head where the exhaust port sticks out, don't use the manifold as your target. If temp readings above are duplicated, rotate pump #1 a tad clockwise and #4 a tad counter clockwise and retest.

I noticed that there are 2 types of injector pumps. I suppose the distance from the base to the spring cap is the same. #4 injector has several shims (7). I have pondered your 2 shim method since I read about as many a 4 a norm. Just pondering. I have to load it to really test the performance of the diesel engine.

 

[majoday]

Well, today I started the MEP-803A. It ran rough but smoothed out a little. I have new injectors. Where on the exhaust do most folks measure heat? I had higher temps on #4 and lower temps on #1 and #2 If I measured on the robust part below the manifold the range was #1 188 (192 w/ cardboard) , #2 195, #3 198, #4 201. I changed IJ pump settings and improved, somewhat. When I measured at the manifold w/cardboard, the front 2 are cooler than the back 2.. I had one upset, It looked like an IJ problem on #4. temps went down. It was good to mess with the unit and to run it.

 

[Ray70]

I usually measure the underside angle of where the exhaust port casting sticks out of the head, just be careful as the fan can play tricks on you, making temps seem lower at the front of motor.
Block the air for a little bit, then measure temps.

 

[majoday]

I usually measure the underside angle of where the exhaust port casting sticks out of the head, just be careful as the fan can play tricks on you, making temps seem lower at the front of motor.
Block the air for a little bit, then measure temps.

Thanks, I reviewed a previous post you shared and this even makes the point more clear. I used the cardboard as you suggested, It worked. # 4 had an injector pump or IJ problem and really cooled down and white smoke came out. I shut it down and restarted it. That cleared the problem. # 4 has 7 shims. I have considered your 2 or 3 shim method for all of them. The set is a 2000 model. The #1 #2 look rusted much more than #3 or #4 (which looks much better). I have wondered if the IJP's are original to the set or were the set's IJ's cannibalized since the set had not run in years. (78 hrs). The set's fuel system was plugged with reddish gunk. Thank you for your help.

 

[Guyfang]

I think the most I ever saw was 3 shims. Something fishy there.

 

[Ray70]

Wow, 7 shims? I think that will make that pump fire off a little late. I've had a few sets that would smoke gray/white out of 1 cly. until it warmed up. They had probably 4 or 5 shims , removing a couple shims ( leaving 2 in place ) fixed most of them.

 

[Guyfang]

Sounds like someone, or someone's wasn't looking, when they put it together, or was inhaling herbal burnt gases.

 

[majoday]

Sounds like someone, or someone's wasn't looking, when they put it together, or was inhaling herbal burnt gases.

The unit went to the Red River Army Depot. Someone purchased it for a few hundred $. I bought it for $750. The seller said they made it start, but it would not run. I found this site. I dismantled the fuel tank and found watery diesel and a quarter inch of red sludge. The filters were also loaded w/ sludge as were the lines. I removed and cleaned the injectors and the I/J Pumps. It runs fairly good. I think the genset was sitting unused for a long time. The oil was pretty. The air filter was clean (2010 date). It may have been in a local guard unit somewhere in this 4 state region, perhaps in perpetual AWAP status as a parts donor. Who knows? I will proceed to follow Ray's advice on the shims. Experimentation is a good thing when proceeded with caution.

 

[Guyfang]

I saw some strange things come out of RESET and Army Depots. They are human too. Its rare, now a days. But early RESET was real bad.

 

[majoday]

I saw some strange things come out of RESET and Army Depots. They are human too. Its rare, now a days. But early RESET was real bad.

I did not know that. Looking at the overall condition of the set, the IJP's look the worse for weathering rust. The best one, in appearance was #4. The rest had significant rust and pitting on the lower part. However, all looked good when disassembled and cleaned.

 

[Guyfang]

In reset, if it worked, it did not get replaced. There were exceptions of course. But in the norm, if it worked, it stayed on the set.

 

[majoday]

In reset, if it worked, it did not get replaced. There were exceptions of course. But in the norm, if it worked, it stayed on the set.

The internals of the IJP's may really be quite good and the cosmetics poor. I will put a high-pressure gauge on the IPJ's this week to check pressure levels.

 

[majoday]

Looks like the subsequent posts have you moving in the right direction.
I'll throw Uniquify's post into this thread too.... for future searchers to find metering pump pictures more easily!

Mep-803a motor locking up at 0 and 180deg

Here's what my stuck pump looked like. The large spring at the bottom is compressed. The fuel lever that fits into the rack couldn't rotate left or right. Took the top off the fuel pump with a 17mm. It's normal right-hand threads. Looking inside, the plunger is the shinier piece in the...

steelsoldiers.com

Hello Ray. I reflected on the sound of the motor. It seemed as if the timing was retarded (Working on motors as a self-trained mechanic since I was @ 15, now 75). So, I removed the injector pumps, one at a time, removed the shims and replaced the I/J's with 2 Black shims and 1 Green for each I/J. Started up and ran with a good sound. the picture is of the remaining shims. 8 Black shims were used as well as 4 Green ones. So, this unit had 17 Black Shims, 3 Grey ones and 13 Green ones affecting the running of the unit. Thank you for sharing your insight on Shim utilization.

 

[Ray70]

Sounds like someone may have owned stocks in the shim company! That's a whole lot of shims to be in one machine. I've never even seen gray shims, are those thicker than the black or somewhere in between the black and the paper thin green ones?
Glad to hear that it's running ( and sounding ) good now!

 

[Guyfang]

Thats why I always looked in the Injector holes. Every once in a while, the injector had a copper washer on it, and another was in the hole. Never hurts to look!!

 

[majoday]

Sounds like someone may have owned stocks in the shim company! That's a whole lot of shims to be in one machine. I've never even seen gray shims, are those thicker than the black or somewhere in between the black and the paper thin green ones?
Glad to hear that it's running ( and sounding ) good now!

02.13.5 Fuel Pump Shim Packs Extreme care must be taken to ensure that the individual shim packs that are fitted between each fuel pump plate and the crankcase are retained with their original respective cylinder. The colour coded shims are available in three sizes: Green ........ 0.075mm (0.003in). Slate blue .. 0.125mm (0.005in). Black ......... 0.250mm (0.010in) I incorrectly identified the 3 shims as grey. They are Slate Blue (Somewhat Grey to the uninformed mind). From the L/P Shop Manual