Plode's M923A2

[Piper Cub]

Truck's looking really nice!

 

[plode]

I still have yet to decide. Green or black paint under the truck? What do you guys think?

 

[R Racing]

Green would be correct. Not sure how black will look. Also black seems to show dirt more.

 

[Piper Cub]

I think black looks good with solid green. But green definitely is correct and shows less dust.

 

[Carlo]

I did use black once and then I was sorry. To much commercial and not enough army look.

 

[plode]

I think green will be easier. No worrying about overspray or anything like that...everything gets it!

Next question...what is this valve? I cannot find it in any of the TM's or on the Cummins Quickserve parts online... It's threaded into the block, just forward of the fuel transfer pump.

(snapchat is handy for circling items of interest )

 

[plode]

No one?

 

[Carlo]

It's a speed drain, no? Is this the side of the block?

 

[helomech]

My truck is sand tan, but the bottom is black. It came like that from the army.

 

[Scott88M]

I'm pretty sure that is for taking oil samples to be analyzed before oil changes. I never did that on m939s but they made us on m915s probably because we were a long haul company and put on thousands of miles.

 

[plode]

It's a speed drain, no? Is this the side of the block?

I'm pretty sure that is for taking oil samples to be analyzed before oil changes. I never did that on m939s but they made us on m915s probably because we were a long haul company and put on thousands of miles.

Not too sure how the valve works, but at least it rules it out as a spot I can run a drain line into from the oil breather system I'm putting together.
Thanks guys.

 

[plode]

Went all over the truck today greasing every fitting I could find. Used up 2.5 tubes of grease so far. I still have to hit a few more. The ujoints on the one driveshaft I need the needle fitting to get to the grease fittings, and the steering column I couldn't get the u joints to take any grease. The hood pivot also wouldn't take any grease. Might be clogged or something.

 

[plode]

Got the needle fitting today and hit the final fittings early this evening. I tried clearing out the hood pivot, still won't take any grease. Even tried heating it up with the propane torch to clear out any hardened grease.

After that I took it out for a drive and I have to say...that truck clearly needed the grease. It rides noticeably smoother now.

Next up is the oil change, I have the oil and filter just have to get around to doing it. I need to get a new belt for it too...from somewhere that doesn't want $60 for it.

 

[plode]

Well I bought the complete ABS retrofit kit off a member on here. Got the air dryer swapped out for a brand new unit(cheaper then buying the rebuild kits), also installed the correct valve up in front of the front axle. The LQ-2 valve is not the correct valve for ABS trucks. It came with the same valve I removed when I installed the LQ-2 valve..thinking it was the correct one.

Took it out for a drive, drove around for about an hour and a half. Did some minor off roading down some dirt roads and a road under a set of power lines.
The first dirt road I drove through some ruts that I saw a picture of a lifted F250 stuck in last week. The truck drove through it like it wasn't even there. The power lines I went down were a bit...different. The road was very sandy. And I guess at some point the state plowed it, so it had berms on either side. Well those berms were the exact width of the trucks tires...so it felt a little like being on a train. Didn't lower tire pressures, so did all of this at ~60psi.



I was surprised that was all of the mud that got on it, but I guess with 49" tires stuff that was deep on 32's isn't so deep anymore The tires did manage to fling it all over the place, including a couple of chunks on the roof.
I also realized the truck is too tall. I scraped on more low hanging trees..it scratched up the paint pretty good in some places I was VERY nervous at one point on a paved road...there could have only been a couple of inches clearance between the spare tire davit and power lines going over the road.

The truck ran beautifully, transmission temps stayed good and cool.
I also finally determined where the oil leak is on the side of the motor. At first I thought it was the power steering pump, but now I see its coming from the compressor. There is a round gasket near the back "half" that it appears to be leaking from.
Not sure if I should just get a replacement compressor or fix the one I have.

Oh and for the people who said the Behr paint(marquee) was fine on the exhaust pipe...wrong. The section under the cab before the muffler, the paint has turned black. And the paint near the top of the stack has begun peeling. It's the only place on the truck that it's doing this, so IMO it has to be from the heat.

 

[plode]

Anyone have a source for parts for the air compressor?
I tried contacting a Cummins dealer, but they said they only show the compressor as a unit, not broken down further into parts. I cannot find a parts diagram for the compressor anywhere online either.

I believe it is leaking oil from somewhere on the compressor(not the oil line), but before I go tearing it off of the truck I need to source at least the flange gaskets. It's leaking oil pretty good...all the way down onto and covering the front differential. Not too many Cummins dealers seem to be interested in online ordering/shipping.
It's either I find these parts, or I'm stuck paying $319+tax for a replacement compressor from Napa.

 

[Carlo]

Anyone have a source for parts for the air compressor?
I tried contacting a Cummins dealer, but they said they only show the compressor as a unit, not broken down further into parts. I cannot find a parts diagram for the compressor anywhere online either.

I believe it is leaking oil from somewhere on the compressor(not the oil line), but before I go tearing it off of the truck I need to source at least the flange gaskets. It's leaking oil pretty good...all the way down onto and covering the front differential. Not too many Cummins dealers seem to be interested in online ordering/shipping.
It's either I find these parts, or I'm stuck paying $319+tax for a replacement compressor from Napa.

Is it not a bendix compressor?

 

[plode]

It's a Holset(Cummins) SS296 compressor.

I just pulled the power steering pump off of the back of the compressor and oil dumped from the cavity where the two connect via splines. So it's just a question of if it's the rear main seal on the compressor or the front seal on the power steering pump.
Not sure how to figure out which one is leaking...guess I can clean it up real nice, leave the power steering pump off and fire it up and see if oil starts leaking from the compressor side. It should be safe to run the engine without the power steering pump on it, right?

 

[Rusty1340]

I've read your entire thread and have to say good job you've come a long way, at the same time I'm now a little nervous because I'm looking at a 1990 923A2 this weekend with 30,000 on the clock and after seeing what you worked through I'm not sure I could. But now I know too some of the things I need to look at. Keep updating and Thank you for the brief education.

 

[plode]

I've read your entire thread and have to say good job you've come a long way, at the same time I'm now a little nervous because I'm looking at a 1990 923A2 this weekend with 30,000 on the clock and after seeing what you worked through I'm not sure I could. But now I know too some of the things I need to look at. Keep updating and Thank you for the brief education.

Thank you for reading. None of it has been that hard...just time consuming and trial and error.

I cleaned the air compressor side off, and I started the truck up today with the power steering pump off. Oil began to leak out of the area where the splines come out...so it's definitely going to need a seal or a gasket replaced.
I don't know if the PS pump is leaking as well, I don't have any real way of checking that. I do know that it leaked out overnight a good bit all over the frame rail where I had it sitting. Don't know if that was residual from the air compressor side leaking, or if the PS pump is leaking too. I'm going to clean it up, and let it sit a few days and see if more oil leaks out and if the level in the reservoir goes down.

So now...what to do about the compressor?

 

[plode]

FINALLY found a parts diagram for the SS-296 compressor. I don't know what engine this diagram was for, but it's not the 6CTA, but I figure the internals of the compressor itself will still be the same.
Here's the parts diagram:

Well, that came out entirely too small...lets try this:

For the life of me, cannot figure out where there are any seals in this diagram. Is it just open on either end and usually the gaskets keep it from leaking out?

If that's the case, it's easy...I can just put on a new gasket and be done with it!