Introduction and a question about my MEP 802a

[kloppk]

The +24 circuit from the batteries to the front panel and control cube go thru diode CR1. Just CR1 will cause a 0.7 volt drop. The additional 0.3 or so would be normal for wiring and switch contact resistance.

 

[2Pbfeet]

I figured I would give a quick update. Before I did anything I disconnected and charged both batteries. While they were disconnected I removed S1 and sprayed it down with DeoxIT. Replaced it and reconnected the batteries. Turning S1 to Prime and I still got a 5 second delay. Next I disconnected the Facet fuel pump (E2) and tested the voltage at the plug. 23.8 volts. Checked the batteries and had 24.8 so losing voltage. Possible bad contacts on S1...however there is no change in voltage when S1 is in Aux Fuel position. My next step will be to measure voltage at S1 at terminals 3 and 5. I'll also measure at terminal 6 to make sure I'm getting 24 volts to S1. If those are good I will follow the schematic. It looks like it goes through the normally closed contacts of K12. I see a few taps off of the line that I will be able to test. Tomorrow I am going to run direct power from the batteries to E2 and see if it comes right on. One final hint towards the healther of the fuel pump is when I switched S1 to Prime, I heard the fuel pump make a very quiet noise before it kicked on. Could it be low voltage or a bad pump? I am leaning towards a bad pump because I cant imagine a pump would stop running down 1 volt. Searching for the Airtex pump I found them hard to find in stock unless I wanted a chinese knockoff. I did find a Carter pump with the same specs. Part number P74018 24volt. Has anyone used one of these?

There is an older thread that suggests that pump;

802/803 fuel pump fittings

It's been discussed that the Airtex e1074 is the replacement fuel pump for 802/803s , but where do I find the specs of replacement fuel line ? (Circled parts) Nsn #s lead to no actual description of said parts. Or did I overlook it somewhere, crosseyed from chasing #s. Thanks Brian

www.steelsoldiers.com

My recollection is that @DieselAddict here talked to Airtex/Carter and got the skinny on the replacement.

MEP-8xx series fuel pump

MEP-802/803 fuel pump Howdy, The 800 series TQG has 2 different fuel pumps. The older style is a square Facet electric fuel pump. The newer style is a round Airtex E1074 fuel pump. This is the primary pump location item. A lot of the units already have these mounted, or have been replaced with...

www.steelsoldiers.com

He wrote that Airtex was acquired by Carter and various models were/are being phased out, but I don't recall the exact replacement pump. With a few fittings, I am sure you can make it work. I think that P74018 comes with 5/16" fittings, and you can go from there.

All the best,

2Pbfeet

 

[Summerpaws]

The +24 circuit from the batteries to the front panel and control cube go thru diode CR1. Just CR1 will cause a 0.7 volt drop. The additional 0.3 or so would be normal for wiring and switch contact resistance.

Thanks for that. Saves me a ton of work! That means it's the pump. I will order the Carter pump tonight. You guys are awesome. By the way, I ran a 75 to 100% load test for an hour. Worked perfectly. Temps, oil pressure, voltage and frequency were right where they should be. After I install the pump and all is good I'm doing a full PMCS on the machine even though it was done 50 hours ago. Judging by the smell of the fuel, it's sat for a spell.

 

[Summerpaws]

There is an older thread that suggests that pump;

802/803 fuel pump fittings

It's been discussed that the Airtex e1074 is the replacement fuel pump for 802/803s , but where do I find the specs of replacement fuel line ? (Circled parts) Nsn #s lead to no actual description of said parts. Or did I overlook it somewhere, crosseyed from chasing #s. Thanks Brian

www.steelsoldiers.com

My recollection is that @DieselAddict here talked to Airtex/Carter and got the skinny on the replacement.

MEP-8xx series fuel pump

MEP-802/803 fuel pump Howdy, The 800 series TQG has 2 different fuel pumps. The older style is a square Facet electric fuel pump. The newer style is a round Airtex E1074 fuel pump. This is the primary pump location item. A lot of the units already have these mounted, or have been replaced with...

www.steelsoldiers.com

He wrote that Airtex was acquired by Carter and various models were/are being phased out, but I don't recall the exact replacement pump. With a few fittings, I am sure you can make it work. I think that P74018 comes with 5/16" fittings, and you can go from there.

All the best,

2Pbfeet

Thank you! I will let you know on the fittings. Thankfully, once the lift pump runs, it stays running. So glad I found this site! The only other thing on my list is to get a MkII or newer S1. I'll post here and see if someone has one after I get the fuel pump done.

 

[Summerpaws]

I have a quick update and a question. After a lot of reading on this forum and a bit of internet sleuthing, I bought a Carter P74018 fuel pump. It's pretty much a plug and play. My next step is to replace S1 to the newer all metal one. I will post on the classified here to see if someone has one rather than jump through hoops to buy one on line. I'm on a tight budget so I'm saving my pennies until I can pay cash. In the meantime I want to see if I can make the one I have continue to work reliably. (It works fine but doesn't feel all that smooth) Jeepadict suggested I use Deoxit on S1. Looking closely at the switch I don't see a way that the Deoxit can get inside to the contacts. Before I remove the switch and see how I can get the cleaner inside the switch, I did a forum search to see if anyone had posted about disassembling the switch and found nothing. My thinking is that once I remove the screws I may be able to get the Deoxit in through the screw holes but I figure that before I do that I would ask here.
By the way, I did an 80% loaded run for an hour and the genset seemed pretty happy overall. The only thing I saw that drew my eye was it ran at 190 degrees on the gauge. Using a heat gun showed a temp of 188 on the upper radiator hose. It never moved any higher.
Thanks again for this forum!

 

[Guyfang]

Take the gage with a grain of salt. And the gun showed 8 degrees difference between the normal temp the set should and likes, to run. I would not worry about it a bit. Pump it up to 100% load, and let it run two hours. Also, have you flushed the radiator? New coolant?

You can loosen the screws on the S1 a TAD, and get detox to run into it. S1 works. So you have time to look around for the best price for a new one.

 

[Summerpaws]

Take the gage with a grain of salt. And the gun showed 8 degrees difference between the normal temp the set should and likes, to run. I would not worry about it a bit. Pump it up to 100% load, and let it run two hours. Also, have you flushed the radiator? New coolant?

You can loosen the screws on the S1 a TAD, and get detox to run into it. S1 works. So you have time to look around for the best price for a new one.

Thanks Guy. I wasn't worried about the temp as it held steady for an hour but reading as much as I can I found that the proper temp seems to be 180 I did see 190 and some 160 reading as well.
So I take it there is no easy way at the innards of the switch. I'll work the Deoxit in as much as I can and hope it helps.
I plan on doing a full service once the weather warms up here. The records show that the last full service was 25 hours ago but back in 2020. I like to do everything because that way I know it's good to go.
My next load test will be at 100%. If I turn on 2 elements on my stove plus the load of the rest of the house, I am at 26 amps. My dryer pulls 30. Maybe I will do the next load test when my wife does a big load of laundry. That way I won't be heating up the house with the stove.