Old Boss Plow?'s

[BenB]

I got a new plow truck a couple months ago and have a couple questions. The truck's an old Army 1985 Chevy M1008A1 and it's a beast. The plow's a Boss 8.2 V, but it looks like the mount was completely custom fabbed, probably by a National Guard soldier that knew how to weld, not completely clean, but seems solid. It's been designed to drop the plow, but lights, hydraulic motor, and main lift cylinder stay on the truck.

Searched the forum and found a few things but still have a few questions.

1.I'm not sure how old the plow is, hydraulic valve assembly matches the drawing in the RT2 manual from the Boss site, but the motor assembly says JSB. Is this orginal or is the Boss assembly hooked up to a different motor? Mounts certainly cosutom and not an RT2

2. No drain plug? Is the fluid changed by dropping the whole reservoir by loosening four small screws?

3. Plow raises slowly but only sometimes, I plan on replacing a couple hoses, cleaning out the screen, draining and putting in new fluid, then seeing if the valve or coil needs replacing. Anyway to test the lift valve or coil? Do you just unscrew the valve from the manifold to check it for contamination?

Thanks for any help.

 

[kurtandshan]

Looks to me like an original (rt1) the light tower looks fabbed but other than looks like all standard Boss of that era.

 

[jhenderson9196]

JSB stands for John S Barnes, a popular hydraulic mfg. for a replacement pump .

 

[Yooper75]

Definetly an old RT1 plow you don't see many of them in good shape and being used any more. Nice truck and plow.

 

[tuney443]

B&B will definitely want to see this.If he doesn't chime in soon, I'd PM him.

 

[maverjohn]

I have the same plow, It's a rt1 looks like early model, The mount looks home made and the control valve should be under the hood, It's ok to have the motor out side if it's protected but you should move the control valve, just add longer hoses. you should also move the salenod to under the hood.
With a paint job that plow will look new and work well for you.

 

[BenB]

Thanks for the info and the tips. Cleaned the screens and checked valves and coils tonight. I just removed most of the hoses, had one leaking at the wing, of course I can't get that one off, got it soaking with Kroil penetrating oil now, will try again in the morning. Any other tips for loosening it? Don't want to bang on it too hard and ruin the cylinder.

I'll look and see if I can move the control valve and solenoid. Not too much room under hood, there's a lot of extra military stuff under there. Valve assembly looks in good shape so not sure if I'll bother moving it, this isn't a commercial rig, stays chained up all winter so it doesn't get a lot of road wear, may make a cover for it when I have the plow off in the summer.

Thanks again.

 

[B&B]

Looks like a nice classic rig. Those good old units are easy to work with and are nearly indestructible. The pump is probably original to the plow, or at least it's the correct brand and vintage. The pump and manifold are acceptable where they're located but under the hood would be far better if you up to relocating them, much better protected from water intrusion and the under hood heat helps to keep them dry and working reliably, they'll easily out last the truck then. Not that the truck won't run forever either.

To remove stubborn fittings cut the hose off right behind the fitting and use a six point socket and a little heat to break it loose. Saves from rounding the fitting off.

 

[BenB]

Thanks for all the info, I was hoping you'd chime in B&B, I read through a lot of your posts searching the site. I'm hoping the truck will last me forever, it's pretty amazing it only has 19k miles and it hasn't rolled over, confirmed it from the military records. I've done some minor work on it and added a radio but she runs great and pushes a ton more snow than the k5 blazer I was using, love the v plow!

 

[Bashby]

pretty cool truck, I'd be tempted to paint the plow camo, you know just to make sure nobody else on the block has one just like it!

 

[BenB]

I was thinking of painting teeth on it, like the old bombers, maybe a pinup girl on the front fenders?
I'm also going to get my Alaska Veterans license plate to put on it. Plow and mount definitely need paint next summer.

Got the stuck fitting off with visegrips and a little heat, looked at moving the motor and valves up under the hood, but that will take some engineering and more time than I have right now, looks like I can move the solenoid pretty easily though.

 

[maverjohn]

I like your plans for painting the plow and truck, if you do paint it like that you will have to post some pic of it.
Move the control valve when you have time, like summer. But I would move the solenoid sooner. keep us posted on how the truck and plow are working out for you.

 

[BenB]

Two quick ?'s

Does the solenoid need grounded? Currently it has two large cables, from the battery and to the motor and then one small yellow wire from the control switch. It's screwed to the bottom of the motor.

Haven't gotten an answer on draining fluid without a drain plug, does the reservoir just taken taken off with those four small bolts?

Thanks. Defintely will post pics after the paint job next summer. These are great plow trucks, worth looking into if you are up for a little work. A quick run down of specs for those not familiar with them:

Military rated as 5/4 ton
6.2 Diesel
2900lb payload
Dana 60 front axle
14 bolt rear
Detroit locker
4.56 gears
4WD high and low
can be found with low miles
and perhaps most important...in cab rifle holders
and all the tech repair manuals are available

Drawbacks
Topspeed only 55
24v starter and some odd wiring
no stock radio

 

[B&B]

Yes the motor relay is self grounding so it needs to either receive good ground from it's mounting points, or better yet, run a dedicated ground wire to either of it's mounting bolts from a battery to accomplish the same (but more reliable) results.

The very early Barns pumps had no drain on the reservoir so yes you need to physically remove the reservoir to drain. Good opportunity to clean it out and check the internal filters while it's off though. Simply remove the four attaching screws and gently work it off with a screwdriver. You'll find a large O-ring on the manifold that seals the reservoir and unless it looks really bad are almost always reusable. Just apply a little fluid on it before reassembly and add a little anti-seize to the screws to ensure the next service will be pain free and you're all set.

 

[BenB]

Thanks again B and B, will do tomorrow before I put the new hoses on! I just didn't want to open a can of worms in case that part wasn't supposed to be removed.

 

[BenB]

Dropped the reservoir, boy it needed it, lots of fine metal sludge, there was a magnet in there at least, but I had to unmount the motor in order to get the tank off. All new hydraulic hoses and no leaks.

One question regarding the lift cylinder though. Before I started the plow would someimes not want to lift, seemed like this was due to the fluid getting low due to the leaks, after topping it off it would seem to get better. After changing fluid the motor runs and I will start to lift the plow in V but won't always raise the whole way, in scoop if won't lift at all. I tried jacking the plow up and dropping it a few times to force out any air bubbles, but still no luck.

My thoughts are one of the following:

an air bubble in the cylinder, is here a good way to purge it or just keep working it, most of the threads seem to say it should self purge any air?

batteries test at right voltages and no troubles starting but maybe they are weak and need replaced, they were manufactured 3 hrs ago

and lastly, and hopefully not, could the motor need rebuilt?

 

[BenB]

Oh, I did test the coils and valves earlier and they are working

 

[B&B]

It isn't an air problem Ben unless it's low on fluid. Are you sure it's full? A partial raise in vee and no raise in scoop usually indicates a low fluid level. It should be about 3/4" from the top of the fill hole with the lift ram and wings fully retracted. A plastic wire tie makes the perfect dip stick.

 

[BenB]

Went down and messed with it some more, check fluid and it was still full, I did top it off twice after installing the new hoses and running it through the motions a few times, that's when I was jacking it up. It was running a bit better, full lift in v, maybe 75% lift in scoop. It seemed to get weaker the more I tried lifting it which makes me think it may be related to the batteries, I see if I can get them load tested this weekend. I guess I should try it under regular plowing conditions, the alternator may just need a second to catch up.

Thanks for the dip stick tip, I made one out of some scrap wire with a loop bent into it to keep me from dropping it into the tank.

 

[BenB]

Update, found some corroded wires so I replaced all the battery and plow cables and moved the solenoid up under the hood at the same time. I was hoping that would make a difference but no change in the plow. Batteries are always testing 12.56-12.7 in the cold and I found no bad cells with a battery tester, I'm still going to get them load tested today, but I'm thinking the problem may be in the pump motor. Tried to use the plow as normal, warm up the truck drive it a bit, then try plowing, same issues, wings work fine, but raising the plow it sometimes struggles, even in V.

Can the brushes be replaced or the motor rebuilt? If the batteries test ok, I will have to take it down and have the dealer test the pressure and amp draw.