What have you done to your CUCV today/lately - Part 2

[Keith_J]

Part 2 of coolant flush. I used 2 quarts of Blue Devil, then drove it for two weeks, still a good bit of silicate buildup in the tubes and rusty sediment so I am repeating it until it is clean. Got a mechanical water temperature gauge (capillary tube type) so now I can see the relationship between coolant and exhaust gas temperatures, handy to know when pulling.

Next mod is secondary transmission cooler, mounted downstream of the header tank cooler.

 

[911joeblow]

Part 2 of coolant flush. I used 2 quarts of Blue Devil, then drove it for two weeks, still a good bit of silicate buildup in the tubes and rusty sediment so I am repeating it until it is clean. Got a mechanical water temperature gauge (capillary tube type) so now I can see the relationship between coolant and exhaust gas temperatures, handy to know when pulling.

Next mod is secondary transmission cooler, mounted downstream of the header tank cooler.

OK call it a shameless plug but...

If you add a Paradox By Design Cooling Upgrade kit you will find all the remaining gunk in the system is a fast way. The reason it is taking so long to clear the system is the rear of the block has horrible pockets that hold air, rust, grit, etc. After our system is in place the rear of the block is opened up to the rest of the cooling system and is constantly bleed as you go.

https://paradoxbydesign.com/collections/cooling-upgrades/products/cucv-coolant-upgrade-kit

 

[Keith_J]

OK call it a shameless plug but...

If you add a Paradox By Design Cooling Upgrade kit you will find all the remaining gunk in the system is a fast way. The reason it is taking so long to clear the system is the rear of the block has horrible pockets that hold air, rust, grit, etc. After our system is in place the rear of the block is opened up to the rest of the cooling system and is constantly bleed as you go.

https://paradoxbydesign.com/collections/cooling-upgrades/products/cucv-coolant-upgrade-kit

Running one right now. I'm the customer with a M1031 and the need for a slightly longer hose.

 

[rustystud]

I replaced the rear brakelines and hose and while doing that I found out the proportion valve is broken.

I have been searching for a part nr and could not find it.
Is there a replacement part for the original?

For now I have connected the line directly to the hose.

Go to "Summit Racing Parts" and buy an "adjustable" proportioning valve. That way you will not lock-up your rear brakes and possibly have an accident. Also as a plus, you can fine tune your stopping ability since no vehicle is identical. The factory just aims at the middle ground and hope it fits all vehicles.

 

[911joeblow]

Running one right now. I'm the customer with a M1031 and the need for a slightly longer hose.

Haha! Its on the way!

 

[emeralcove]

Not done today or lately but about one year ago the door lock on the drivers side had gotten to the point I could no longer insert the key all the way, with jiggling sometimes but it was so hard to turn I worried the key would snap off. I figured I would be buying new door locks in order to fix it and in the short term resorted to using the passenger side door to get in, (yes it was a pain the "butte") About that time my wife bought an almost new horse trailer and the previous owner included a can of Boeshield to use on the locks and hinges. They went on and on about this lubricant and how good it was, it appeared to be just another WD-40 to me. Well I had used graphite lock lubricant with no improvement on my door lock so I didn't expect this Boeshield to be any different. Big Pleasant Surprise, not only did it work so well it felt like the key wasn't even connected to the lock linkage any more but yet the door lock popped up and down when the key was turned. The reason for waiting a year to say what I did lately was to see if it had a lasting affect, a whole year later the door lock still works as smooth as a new car. A lot cheaper than new locks and a lot less labor.

 

[shotty]

Pulled the driver seat of my 1028 to take it to get upholstered and have some heated seat elements installed. One of the mounting bolts was already broken. Broke a second one removing the seat, both on the driver side. Guess I know what I'm doing this afternoon...

While I'm here, can someone confirm for me if the bench seat is supposed to latch back? Mine just folds forward whenever you want it to.

 

[rustystud]

Pulled the driver seat of my 1028 to take it to get upholstered and have some heated seat elements installed. One of the mounting bolts was already broken. Broke a second one removing the seat, both on the driver side. Guess I know what I'm doing this afternoon...

While I'm here, can someone confirm for me if the bench seat is supposed to latch back? Mine just folds forward whenever you want it to.

There is a latch that is suppose to hold the seat back upright. They can break pretty easily.

 

[Keith_J]

Installed the mechanical coolant temperature sensor and digital ammeter/voltmeter. Used the left (driver's) alternator ground for the ammeter shunt. Numbers? Idle with no other consumers running and the system stabilizes at 6 amps. Headlights jump it to 26 amps. High beams up to 32. Heater blower with high beams is 38. Throw in high windshield wipers and its 48, give or take as the current varies. Voltage is 29.4 +_ 0.6 depending on load and engine speed.

Didn't do but a 6 mile road test for coolant temperature, hardly got above 150 F. I had to use a few fittings to make it work, its a bit Rube Goldbergish. So I still have to find the correct fittings and wait for the longer coolant bypass hose. Too ugly to post a picture, no leaks so it stays. The gauge is permanently mounted next to the stock analog voltmeter, I didn't have a 2" hole punch so I used a rotary file in a 1/4" die grinder, fast but noisy. If the digital voltmeter works well, the EGT will go into this hole. The digital voltmeter is rectangular and will go into a new PTO generator panel.

 

[Matt S]

I had the opportunity to remove and replace my radiator twice. The second time I opted for a re-core. So far no leaks. After seeing the old core, I don't understand how it wasn't over heating.

 

[TGP (IL)]

Pulled the driver seat of my 1028 to take it to get upholstered and have some heated seat elements installed. One of the mounting bolts was already broken. Broke a second one removing the seat, both on the driver side. Guess I know what I'm doing this afternoon...

While I'm here, can someone confirm for me if the bench seat is supposed to latch back? Mine just folds forward whenever you want it to.

The civilian trucks had a latch.

My M1028A2 does not.

In fact I haven't seen a military CUCV truck with one, but I've only seen a
Half dozen or so.
Tom

 

[TGP (IL)]

I had the opportunity to remove and replace my radiator twice. The second time I opted for a re-core. So far no leaks. After seeing the old core, I don't understand how it wasn't over heating.

Changed my radiator also Monday.
Sent my original to radiator shop for repair/rebuild.
The aftermarket junk is just that.

Tom

 

[Sharecropper]

I replaced the rear brakelines and hose and while doing that I found out the proportion valve is broken.

I have been searching for a part nr and could not find it.
Is there a replacement part for the original?

For now I have connected the line directly to the hose.

GM issued a Dealer Bulletin in 1988 to completely remove that rear proportioning valve. I don't have a copy of the bulletin to attach here, but it is Bulletin 88-320-5 which you should be able to obtain through your local GM dealer. I took mine off and threw it in the dumpster. I also installed rear disc brakes, and the combination of both caused my truck to stop on a dime going forward or backward. If you can get a copy of the bulletin, it would be helpful to others on SS to have a copy.

 

[cucvrus]

[h=5]Re: brake proportioning valve malfunction?[/h]




Number: 83-T-61

Section: V

Date: July, 1983
Subject: REVISED REAR SUSPENSION ON VEHICLES WITH HEIGHT SENSING PROPORTIONING BRAKE SYSTEMS - 1982-83 "C/K" 30
TO: ALL CHEVROLET DEALERS


1982-83 "C/K" 30 series trucks are equipped with a rear suspension height sensing device that optimizes the brake proportioning valve setting for the load the vehicle is carrying. The height sensing system "fine tunes" the brake balance in vehicles subjected to a range of loading conditions.

Occasionally, vehicle modifications by body builders or owners influence the height sensing device. If a vehicle has had rear suspension modifications that affect its trim height or the spring rate, and the driver complains about the brake modulation characteristics of the vehicle, it is recommended that the height sensing system be removed and the brake system be revised as described below:
FIGURE #1 - REAR SUSPENSION




1. Detach rear brake hose from lever and bracket assembly. Reference Figure #1.

2. Remove lever assembly and bracket from axle.
FIGURE #2 - DIFFERENTIAL




3. Install rear brake hose bracket (P/N 34897

and spacer (P/N 2355099) with a 3/8-16 x 1.38 bolt (P/N 358000 - shorter bolt removed in Step #2) in the upper cover hole. Reference Figure #2. Use Loctite 75 or equivalent on the bolt threads.

4. Attach brake hose to bracket with bolt from original installation.

5. Install a 3/8-16 x 1-3/4 bolt (PIN 14055557 -- longer bolt removed in Step #2) through spacer P/N 14055556 (removed in Step #2) in remaining axle cover attaching hole. Use Loctite 75 or equivalent on bolt threads.
FIGURE #1 - REAR SUSPENSION




6. Disconnect brake pipes from height sensing valve and brake hose, and discard short brake pipe. Reference Figure #1.
7. Remove and discard height sensing valve, bracket and bolts.

8. Carefully reposition the rear brake pipe, and connect it to the rear brake hose.

9. Remove the brake combination valve per section 5 of the Light Duty Shop Manual.

10. Select and install a replacement combination valve, based on the vehicle wheelbase and type of rear wheels, from the chart below:

Valve Part
Wheelbase Rear Wheel Type Valve Code Number

131/135 Single DD 1257200
131/135 Dual EE 1257203
159/164 Single 1257203
159/164 Dual P 1257087


11. Bleed and test brake system per Section 5 of the Light Duty Shop Manual.

ALSO

These vehicles use either a two function or three function combination valve. Some vehicles use a height sensitive proportioning valve in addition to the combination valve.
The two function combination valve consists of a metering valve and a brake failure warning switch. The hydraulic brake lines are routed through this valve to the wheel cylinders or calipers. The metering portion of this valve assists in providing balanced front to rear braking by delaying full hydraulic fluid pressure to the front disc brakes until the rear drum brakes overcome return spring tension and the linings contact the drums. The brake failure warning switch portion of the valve activates the brake warning lamp when there is a loss of pressure in either the front or the rear braking system.
The three function combination valve consists of a metering valve, a brake failure warning switch, and a proportioning valve. The metering valve and brake failure warning switch operate the same as those in the two function combination valve previously described.
The proportioning section of the valve proportions outlet pressure to the rear brakes after a certain rear input pressure has been reached, preventing rear wheel lock-up.
The height sensitive proportioning valve provides ideal brake balance according to weight at rear axle. This valve is mounted on the frame and responds to changes in vehicle trim height in relation to rear axle load. Mechanical linkage connects the valve to a bracket attached to the rear axle.

 

[shotty]

M101A2 cover and roof bows on DIY wood sides



More info: https://www.steelsoldiers.com/showthread.php?183974-M101A2-cover-on-an-M1008

 

[MarcusOReallyus]

Re: brake proportioning valve malfunction?






Number: 83-T-61

Section: V

Date: July, 1983
Subject: REVISED REAR SUSPENSION ON VEHICLES WITH HEIGHT SENSING PROPORTIONING BRAKE SYSTEMS - 1982-83 "C/K" 30
TO: ALL CHEVROLET DEALERS

Heh. First time I've ever reported one of Rick's posts. I wanted to let the mods know there is sticky material right there!

 

[rustystud]

The civilian trucks had a latch.

My M1028A2 does not.

In fact I haven't seen a military CUCV truck with one, but I've only seen a
Half dozen or so.
Tom

Are you sure about that ? If so that explains why my seat back never worked ! I always just thought the latch was broken !

 

[german m1008]

....... me too

 

[Recovry4x4]

My truck is sans latch as well.

 

[shotty]

I was looking around the hinge mechanism on my seat and I found part of what looks to be the locking mechanism just flopping around in there. It's a little bar with that seems like it could crab the teeth on the seat back. It is clearly still missing some parts though.