Keeping a M1009 alive

[CUCV VZ]

Hello all,

I have been on this site for quite some time and have found it very helpful for locating part numbers and guides but it becomes very time consuming digging through forums. I am creating this thread to hopefully get valuable feedback and advice, while tracking my own trucks progress. I am currently in college and have been daily driving my blazer and wish not for a full restore, but to keep up on the vehicle for as long as possible. Below is what I have for a requires attention list:

Electrical (Has 12v conversion):

• Batteries
  • battery tie downs (not the 6TL batteries)
  • battery connectors and misc disconnected wires
• Random voltage drops/surges
• Power drain while driving at higher speeds
• Coolant dummy light intermittent flashing (coolant is always full)
• Front marker light (turn signal constantly lit)
• Heater switch not always functioning
• Need glow plug control switch

Mechanical:

• Harmonic Balancer (Seen a lot on this one needing preemptive maintenance)
• Leaking 4x4 Lockouts
• Brakes (literally everything needs a refresh)
• Differentials
  • Reseal rear cover
  • Obtain a serviceable cover for front
• Steering links & ball joints
• New shocks (maybe springs?)
• Trans & Oil seals

Body:

• It's Michigan, who cares?

As of right now I am mostly concerned about the primary electrical issues and locating the random surges and drops. I will follow up this post with another giving further details about my issues.

Please feel free to recommend any other common problems I should be watching out for!
Thanks

 

[CUCV VZ]

Found the root cause of my blinker failure to be the cheap replacement socket I bought from Advance Auto, built out of Chinesium. Can't even find the unit on their website.

Also just discovered the courtesy light below under the dash by accident, was fiddling around with loose wires.

 

[CUCV VZ]

Rewired a new marker socket in - the replacement one above by Dorman was junk: bulb wouldn't seat and grounding wire fell out. ID no. 85830.

Heater blower switch has poor wiring and requires a lil finessing in order to keep running. Dash was removed by previous owner and left behind a rats nest of splicing.

Glow plugs have been engaging every time since new batter terminal connectors, still on factory system.

Next immediate project will be to sort out the two loose wires I have in the engine bay.

 

[87cr250r]

The 12/24v system works fine. Don't mess around with a 12v conversion.

The stock battery trays work with group 27 and group 31 batteries if you're looking for a less expensive option.

If the low coolant light is flashing check for leaking head gaskets by running the engine with the radiator cap and looking for bubbles.

Rebuild your alternators. They're Delco 27SI units. Parts are cheap. Verify your belts are in good condition. Gates brand belts are the only ones that hold up well on these engines.

 

[CUCV VZ]

The 12/24v system works fine. Don't mess around with a 12v conversion.

The stock battery trays work with group 27 and group 31 batteries if you're looking for a less expensive option.

If the low coolant light is flashing check for leaking head gaskets by running the engine with the radiator cap and looking for bubbles.

Rebuild your alternators. They're Delco 27SI units. Parts are cheap. Verify your belts are in good condition. Gates brand belts are the only ones that hold up well on these engines.

For clarification, the truck has unfortunately already undergone the 12V conversion by one of the previous owners. I am looking into 3D printing blocks to better secure the batteries in the trays.

I have to keep everything on a budget as I am still in college trying to scrape by on pennies.

Also, thank you for the recommendations on coolant light. Not seeing any drop in coolant levels (at least noticeable). I will try to investigate tonight.

 

[87cr250r]

Look closely at the battery trays. There are little metal tabs in the bottom that fit the group 31 batteries to keep them from sliding around. I also believe the trays already have blind welded for 1/4 rod for the hold down. You can use the universal hold downs at the auto parts store with these rods.

What exactly was done to convert the truck to 12v? So you still have the alternators? Do you still have the glow plugs?

What glow plugs are in the truck? The AC Delco 60G plugs are the most most resistance to swelling but also require replacing connectors or grinding the spades down. 13G plugs are the original style. Do not run another plugs!

 

[CUCV VZ]

Look closely at the battery trays. There are little metal tabs in the bottom that fit the group 31 batteries to keep them from sliding around. I also believe the trays already have blind welded for 1/4 rod for the hold down. You can use the universal hold downs at the auto parts store with these rods.

What exactly was done to convert the truck to 12v? So you still have the alternators? Do you still have the glow plugs?

What glow plugs are in the truck? The AC Delco 60G plugs are the most most resistance to swelling but also require replacing connectors or grinding the spades down. 13G plugs are the original style. Do not run another plugs!

I am not sure what plugs are currently in, I received a bunch of parts alongside the truck when I bought it, including boxes for glow-plugs. I will give them a gander at some point this week to see if the old ones or new ones are in there and compare to the ones already in.

I may be mistaken but I think I have a 12v conversion as I only read 12-14v on the system with my multimeter and dash voltage gauge. I have the dual alternator setup and a third one that was included in the extra parts - the two installed match, third seems to be a different make. Replaced the belts not to long ago and the passenger side one is stretched already, which could explain my poor charging.

I ran the engine and allowed it to warm with the radiator cap off like you suggested and saw no air bubbles, the coolant did rise and just spilled out rather than filling the overflow container... is that right?

 

[87cr250r]

If you got boxes of glow plugs someone was probably chasing glow plugs failures with junk glow plugs. I strongly suggest the 60G plugs as it is rare for them to swell during a failure.

Does the truck have a ballast resistor on the firewall?

The starter and/or starter solenoid should have a tag that says 12 or 24v.

Yes, it is normal for water level to rise as the engine warms. No air bubbles is a good sign.

If you want to daily the truck you need Gates belts. No other belt held up in my experience. I even had a Goodyear toss itself. They aren't stiff enough. These engines use a second pulley on the power steering pump as an idler and the two belts fight each other. I was getting 25k miles on a set of Gates belts. Much less on everything else.

 

[CARC686]

Unless you're 3D printing battery risers for free, I'd use wood blocks.