802a starter question

[JR2980]

Well, I'm the winner of 2 802A's from the Ft Meade auction that just closed at 5pm today. I think I got decent units, but it seems to be a crapshoot so we'll see. One of them had the exhaust flap, and the other one I'm guessing had it...there was a thin coat of snow on the entire top, and I'm hoping that if there was no flapper there would have been a hole where the exhaust is.

Anyways, I was wondering about converting these from 12v to 24v - is the starter the only thing that uses the 24v system, and is there a 12v starter that is a direct replacement for the 24v?

If the starter can be replaced with 12v, is there anything else in the system that would require 24v? As I'm typing this, I just thought of the intake preheater and the injectors - are these 24v or is there a stepdown transformer to convert the 12v to 24v? I seem to remember them doing this with some of the old CUCV's where you could swap the starter from 24v to 12v, and everything else was already running on 12v.


Any one done this or have any thoughts on it?



Thanks!

 

[avc8130]

Why?

Alternator is 24V also.

What is the end goal? Save a battery?

ac

 

[JR2980]

Why?

Alternator is 24V also.

What is the end goal? Save a battery?

ac

Why not?

Just wondering - I've got slave receptacles for my F350 and F250 and it would be nice if I could jump off of the genset if necessary.

I dont really NEED to, but if it was easy enough to do, then why not?

 

[avc8130]

Why not?

Just wondering - I've got slave receptacles for my F350 and F250 and it would be nice if I could jump off of the genset if necessary.

I dont really NEED to, but if it was easy enough to do, then why not?

I think the slave output on the generator is more of an "input".

The batteries in the generator are TINY compared to what is found in a 5-ton, or even a Deuce. I think the slave cable on the generator was intended to start the generator from the truck, not the other way around.

ac

 

[JR2980]

I think the slave output on the generator is more of an "input".

The batteries in the generator are TINY compared to what is found in a 5-ton, or even a Deuce. I think the slave cable on the generator was intended to start the generator from the truck, not the other way around.

ac

Thats a good point - but then I could jump the genset off of the truck if I needed to.

Maybe I'm nuts for even considering it, I just like having everything standardized.

 

[avc8130]

Thats a good point - but then I could jump the genset off of the truck if I needed to.

Maybe I'm nuts for even considering it, I just like having everything standardized.

That is one disadvantage to the 24V setup, you can't just jump it from your truck. However, if you do your maintenance runs, it shouldn't be a big deal.

If you are worried about maintaining the charge, talk to "TurboJoe". I think he has a nice 24V charger setup figured out for these MEPs.

ac

 

[ETN550]

The entire low voltage controls are 24 volt. With the one exception that the glow plugs are 12 volt wired in series to use 24 volt as a pair.

This unit has fuel level, oil pressure, temperature shutdowns and gages plus starter and alternator, two 24 volt electric fuel pumps, hourmeter, all relays, etc. etc. And then there is the shutdown control module and the fuel level control module. Those are 24volt potted circuit boards and the electric diagrams are not available for those sub components. So they would have to be re-engineered. Additionally, the generator field is probably excited with 24 volt DC upon cranking. It's not going to be switched over to 12 volt easily, and certainly not economically.

However, to answer your question the starter is available from Lister Petter in a 12 volt model.

Sorry to sound pessimistic about 12volt conversion but there are a lot of details to work out if it is intended to function and be protected as it is now.

 

[Ratch]

Also, the injectors don't use electric. So that'd be one less thing to convert.

 

[ETN550]

I guess if one really wanted to have 12 volts it might be simplist to convert the starter and then add a 12 volt to 24 volt step up transformer and tie it into the existing 24 volt system. I believe there is only a few 24 volt wires coming off the battery connection on the starter that feed all the low voltage circuits.

I think that would be an easy proposition compared to a re-fit.

 

[Ratch]

Btw, most of those units did NOT have a flap and the engines were full of water. The snow made it impossible to tell by the pics, but I previewed that event and visually confirmed most engines were compromised.
Sorry, I hate to be a downer... But if your hopes aren't high, they won't be crushed.

 

[Chainbreaker]

Btw, most of those units did NOT have a flap and the engines were full of water. The snow made it impossible to tell by the pics, but I previewed that event and visually confirmed most engines were compromised.
Sorry, I hate to be a downer... But if your hopes aren't high, they won't be crushed.

Does anyone else find it a bit odd at how many of these units are missing exhaust flaps? Obviously without them the engine is subject to either rain or sand intrusion or anything else that can fall down the upward facing exhaust pipe. Are these flaps that flimsy that they are breaking and falling off or are they being intentionally removed by someone thinking it helps exhaust flow? Would be interesting to know if more of the desert sand colored units have the flap removed as opposed to the olive drab units or is there no correlation to color? Regardless, its a bit distressing to hear of the damage and grief these missing flaps are causing.

 

[Ratch]

They're torn off by poor handling. The housing on mine is damaged in a way that makes it pretty clear something was dragged across it. The flapper is really the only thing that's not flat on the top, and I did see a GL pic of some of these gensets stacked on top of one another (wouldn't want to stand next to that).

The units I previewed generally all had the same type of damage. Some had flappers that were intact, but obviously stuck open, most were torn off, some were partially torn off but looked intact in pics. I don't think its intentional, but it is a very obvious design flaw.
You typically want the exhaust open upward, but there should be a pinhole drain in a trap to prevent the engine from filling with water.

 

[Ratch]

Btw, the exposed opening when a flapper is missing is the muffler outlet, on the opposite side from the inlet. So the engine is still relatively safe from solids falling in there. But even a pinhole in the bottom of the muffler would prevent the engine from filling.

And yes, the flappers are very light and flimsy. They'd have to be for easy opening.

 

[avc8130]

The flappers are gone because they stack the units.

Don't worry, the flapper design SUCKS. Even the unit I have with a flapper is terrible. The flapper fails to close after the machine runs 90% of the time. I'm scrapping the flapper and just going to run a 90 degree black pipe elbow.

ac

 

[JR2980]

The entire low voltage controls are 24 volt. With the one exception that the glow plugs are 12 volt wired in series to use 24 volt as a pair.

This unit has fuel level, oil pressure, temperature shutdowns and gages plus starter and alternator, two 24 volt electric fuel pumps, hourmeter, all relays, etc. etc. And then there is the shutdown control module and the fuel level control module. Those are 24volt potted circuit boards and the electric diagrams are not available for those sub components. So they would have to be re-engineered. Additionally, the generator field is probably excited with 24 volt DC upon cranking. It's not going to be switched over to 12 volt easily, and certainly not economically.

However, to answer your question the starter is available from Lister Petter in a 12 volt model.

Sorry to sound pessimistic about 12volt conversion but there are a lot of details to work out if it is intended to function and be protected as it is now.

Thanks for the info - thats exactly what I was wondering about.

Oh well....one less project!

 

[JR2980]

Btw, most of those units did NOT have a flap and the engines were full of water. The snow made it impossible to tell by the pics, but I previewed that event and visually confirmed most engines were compromised.
Sorry, I hate to be a downer... But if your hopes aren't high, they won't be crushed.

Hopes werent too high, so no worries there!

One of them had the flapper in the picture, so I'm hoping it was one of the few that still had it - if not, then I'll rebuild!


Thanks!

 

[avc8130]

Hopes werent too high, so no worries there!

One of them had the flapper in the picture, so I'm hoping it was one of the few that still had it - if not, then I'll rebuild!


Thanks!

I previewed a lot. The flapper didn't mean anything. Lifted plenty a flapper to find an exhaust full of water.

ac

 

[JR2980]

The flappers are gone because they stack the units.

Don't worry, the flapper design SUCKS. Even the unit I have with a flapper is terrible. The flapper fails to close after the machine runs 90% of the time. I'm scrapping the flapper and just going to run a 90 degree black pipe elbow.

ac

Thats a good idea - I had been considering something similar. Post something up and show us your setup once you get it done - I'd love to see it.


Thanks!

 

[avc8130]

Thats a good idea - I had been considering something similar. Post something up and show us your setup once you get it done - I'd love to see it.


Thanks!

I'm a ways away.

1 of my sets needs a bore/hone/pistons/rings/valve seats cut/valves lapped.
The other needs a new control setup as the harness caught fire.

Yeah...it was a rough auction.

My setup won't look crazy. Just going to go to Home Depot and grab a single elbow and maybe a 6" nipple just to block driving rain. Slap that on top and orient it away from the operator station/refuel station.

ac

 

[zarathustra]

Flapper - I haven't got to look at it too well yet, but it looks as if the exhaust is threaded. If so, why not put a small extenson pipe vertically and a tractor style flapper on it?

I've got a flapper on a Ford 4630 and it works fine.