Starting Over 93 C3500 18:1

[Duvall]

Update time.

I have been driving this off and on over the last year. Mostly off.
A truck without a bed is not very useful unless its pulling a trailer.

It has been running well and no real problems. It is definitely a different animal when it comes to starting in cooler weather. It takes some cranking to get it to start below 50 degrees without being plugged in. That is an obvious draw back to 18:1 compression. I don't plan to drive it much in the cold anyway, so I can live with that.

Partial list of the "to do"

Fuel system update
New rear tires
Front brakes
Complete the air bag system

The paint work is back in progress and hopefully is completed before the first week of May.

 

[Will L.]

Have you switched to the powermaster starter and larger cables being fed from top post batteries yet?
You’re able to draw more current through top post and larger cables by roughly 20%. Then the powermaster does about the same increase.

 

[Duvall]

Have you switched to the powermaster starter and larger cables being fed from top post batteries yet?
You’re able to draw more current through top post and larger cables by roughly 20%. Then the powermaster does about the same increase.

Yes, I have the Powermaster starter.
I still use the side terminal and stock style cables. I had considered making larger gauge cables, but mine are still in good shape.
It does spin very fast with the Powermaster starter.

I really like the cleaner look of side terminal batteries and maybe if they were not new I would consider switching.

I haven't seen any solid data that shows the top post are capable of higher current draw.

Do you have some info on that?

 

[Will L.]

I posted a little years back, from Delco and Optima on there labeling- but it is basically area of the lead in contact.

larger surface area of the terminal conducts more electricity in same amount of time, Like having a larger wire. Then there is the interior lead bussing thatgoes to those terminals. In cars and pickups height restrictions were the main use for lower hood and better aerodynamics. But look into semi truck or heavy equipment and there is no such thing as side post- they simply cannot handle the draw.

If you are content with the time of starting, you can leave it. Just suggestions for helping it start easier.

Another thing that can be done is adding heating element in the air intake to heat the incoming air like is done in engines such as cummins. Obviously some fabrication is required, but you could adapt the cummins unit directly into the intake and wire it to come on with the glow plugs.

 

[WarWagon]

I have had the GM side posts burn out in Exide batteries. (High Resistance) Switched to top posts on those batteries and carried on with the usual extremely short battery life in our extreme heat.

 

[Duvall]

I posted a little years back, from Delco and Optima on there labeling- but it is basically area of the lead in contact.

larger surface area of the terminal conducts more electricity in same amount of time, Like having a larger wire. Then there is the interior lead bussing thatgoes to those terminals. In cars and pickups height restrictions were the main use for lower hood and better aerodynamics. But look into semi truck or heavy equipment and there is no such thing as side post- they simply cannot handle the draw.

If you are content with the time of starting, you can leave it. Just suggestions for helping it start easier.

Another thing that can be done is adding heating element in the air intake to heat the incoming air like is done in engines such as cummins. Obviously some fabrication is required, but you could adapt the cummins unit directly into the intake and wire it to come on with the glow plugs.

I never really considered the interior makeup of the side post battery. When these batteries take a turn for the worse I will probably make the switch to top post.

Its spins over plenty fast. I think it just needs more heat for the cold starts (45 degrees and lower). If its been plugged in or has been running in the last several hours it lights up instantly.

 

[WarWagon]

Do you have the self limiting glow plugs? Do you have a glow plug override switch? IMO the factory timer doesn't give the self limiting plugs enough on time to "glow". I have watched them not glow through a removed injector and cycled the plugs. The old resistor trick to increase time does not work anymore on new controllers.


I would give my 'below min spec' low compression 6.2 30 seconds of glow time and sometimes hold the plugs "on" when cranking. Also push the throttle 1/2 to the floor till it starts to fire. I believe the throttle advice is on the driver side sun visor.

 

[n8in8or]

Do you have the self limiting glow plugs? Do you have a glow plug override switch? IMO the factory timer doesn't give the self limiting plugs enough on time to "glow". I have watched them not glow through a removed injector and cycled the plugs. The old resistor trick to increase time does not work anymore on new controllers.


I would give my 'below min spec' low compression 6.2 30 seconds of glow time and sometimes hold the plugs "on" when cranking. Also push the throttle 1/2 to the floor till it starts to fire. I believe the throttle advice is on the driver side sun visor.

The way I have my truck wired up with the older style controller now and I was surprised how short it cycles the plugs. It fires ok right now, but I bet I'll need to wire in an override.

 

[Duvall]

Do you have the self limiting glow plugs? Do you have a glow plug override switch? IMO the factory timer doesn't give the self limiting plugs enough on time to "glow". I have watched them not glow through a removed injector and cycled the plugs. The old resistor trick to increase time does not work anymore on new controllers.


I would give my 'below min spec' low compression 6.2 30 seconds of glow time and sometimes hold the plugs "on" when cranking. Also push the throttle 1/2 to the floor till it starts to fire. I believe the throttle advice is on the driver side sun visor.

Its been long enough that I don't remember which glow plugs I have. I believe I have the AC Delco because the Bosch were the plague at the time. I do have an override relay, just not installed. My glow plug relay must be old school because it has a fairly long first cycle. At least it seems like it does to me.

I have always been reluctant to use throttle input when starting a cold engine. I always give it the one push to set the high idle solenoid and thats about it.

The way I have my truck wired up with the older style controller now and I was surprised how short it cycles the plugs. It fires ok right now, but I bet I'll need to wire in an override.

How long would you say this glow cycle is? I don't know how long it should cycle.

 

[n8in8or]

How long would you say this glow cycle is? I don't know how long it should cycle.

Hmmm, maybe 5 seconds? I'll try to time it next time I fire it up.

 

[MrMarty51]

Seems the GP cycle time on My 2000 year unit runs about 30 seconds or so. I have never timed it.
Does seem to take longer when the temps is colder and the truck has not been plugged in.

 

[n8in8or]

Seems the GP cycle time on My 2000 year unit runs about 30 seconds or so. I have never timed it.
Does seem to take longer when the temps is colder and the truck has not been plugged in.

The cycle time for DS4 trucks like yours is controlled by the computer. For mechanical trucks like Duvall's the time is dictated by the Glow Plug controller. When I converted the Tahoe to mechanical I retained the computer and used that for glow plug control which gave nice long glow plug burns, but I didn't want all that extra wiring when I converted the K3500 so I changed over to the DB2 controller.

 

[Duvall]

Hmmm, maybe 5 seconds? I'll try to time it next time I fire it up.

That is pretty quick. I think mine is at least double that.

I will time mine as well. I'm not sure if it changes according to ambient temp.

Seems the GP cycle time on My 2000 year unit runs about 30 seconds or so. I have never timed it.
Does seem to take longer when the temps is colder and the truck has not been plugged in.

Thats a long glow time.

The cycle time for DS4 trucks like yours is controlled by the computer. For mechanical trucks like Duvall's the time is dictated by the Glow Plug controller. When I converted the Tahoe to mechanical I retained the computer and used that for glow plug control which gave nice long glow plug burns, but I didn't want all that extra wiring when I converted the K3500 so I changed over to the DB2 controller.

Long burns....

Love it

 

[WarWagon]

Pull an injector and cycle the plugs ... If the plug isn't Glowing red or orange it ain't a Glow Plug! I did this with the 1993 and added the override switch after that. 30 seconds got them hot enough to glow. The controller even with the resistor added to the harness didn't get them hot enough.

I added more time in the tune of the 1995 for glow plugs.

 

[Duvall]

Another quick update.

I replaced the original rear spring bushings with urethane.


Got the fender flares on the bed and the bed mounted.



Changed the rear gears back to the original gearing of 4.10 from the 3.42 I had installed before.



Been driving it more often. I lowered this when I was in the process of going through all the suspension and overall reconstruction. The front has 3" drop spindles and the rear has 4" lowering shackles and hangers. This is all the lower you can really go in the rear without an axle flip and notching the frame. Since I plan to use this truck for towing and possibly a 5th wheel, notching was not favorable to me.



It has some rake that I am not crazy about, but this picture really makes it look worse than it is. There is only 4 1/2" from the frame to the axle, so going lower in the rear is not going to happen. Ignore the dirty wheels.



Went on a short camping trip the end of last month. I have pulled many loads in the 4-6k lbs range, but never anything this tall.
I kept the speeds between 60-65 and had no issues. In 88-89 degree temp the engine was under 210 degrees with a 190 thermostat, with the A/C going. IF I turned on the fan the engine temp would drop quite a bit. The current radiator is a brass/copper unit that had been cleaned and rebuilt before I put this truck back together. I am considering switching to an aluminum unit for better cooling.




Here the trailer is not attached and the rake doesn't look as bad. It still needs some front bumper alignment done because of the frame on the drivers side. I've been waiting to get it on the rack to get this fixed. I did some air relief cutting to this scrap 1996 grill.

I have a new 93 grill to go on once I get the corner marker lenses.



I had been really ginger on the throttle since I've been driving it. The bad luck with head gaskets gives me anxiety as I see the boost climb to 10 psi. Well, this trip broke that up as I looked at the gauge and saw over 15psi when climbing a small hill. So I guess its going to hold together for a little while longer. I haven't decided what I am going to do for air charge cooling yet. I have meth/water kit on hand, so I will probably start with that. Air charge temps quickly climb to 300 degrees when on the throttle heavy in 90 degree heat and nothing to cool the air charge.

 

[MrMarty51]

That is a mighty fine rig You have got there. 15PSI, I would say it will hold together.

 

[Will L.]

If your gonna get the coated aluminum one from Chris- then ok. But many people get heartbroken from trying the swap from copper to aluminum believing the words from aluminum radiator builders that say they cool better, only to discover the truth.

You said IF YOU turn on the fan it cools off- idk electro viscous or electric auxiliary- but if you can turn it on, then start using it sooner. 220 is the point of taking temper out of rings in minutes. 210 does it also, but needs sustained time like 35-45 minutes.
People don’t get, the packaging of this engine was designed based around the gasser engine which was designed to run at 180°.
Diesels and ewer gas engines that are properly planned out to run at 210,220,etc have thicker cylinder walls and better radiators that shed the heat much faster. So yeah- focus on that cooling system next.
Your signature doesn’t have anything listed. Other than having cleaned it- what is it?


On the boost- dude- that compression ratio gives you plenty of room for boost. Is it an abnormally big inducer/ housing on that 40?

 

[MrMarty51]

I drilled three holes through the fan clutch on My truck. Tapped the holes and installed three machine screws to lock the clutch solid. Thanks to Will L (iirc) for that tidbit.
Ambient temps at about 100 or more, kept the engine temp right at 200 on a long steep hill.
Previous it was running right on 217 degrees.
The electro/viscous fan system will be the next components that I will up rate to.
Thanks to AK Dieseldriver for the thread He started then posted in with the components part numbers to get the job done.

 

[n8in8or]

That's a sharp looking rig, Andrew!! FWIW, yours would look dumb with a cap on it.

 

[Duvall]

If your gonna get the coated aluminum one from Chris- then ok. But many people get heartbroken from trying the swap from copper to aluminum believing the words from aluminum radiator builders that say they cool better, only to discover the truth.

You said IF YOU turn on the fan it cools off- idk electro viscous or electric auxiliary- but if you can turn it on, then start using it sooner. 220 is the point of taking temper out of rings in minutes. 210 does it also, but needs sustained time like 35-45 minutes.
People don’t get, the packaging of this engine was designed based around the gasser engine which was designed to run at 180°.
Diesels and ewer gas engines that are properly planned out to run at 210,220,etc have thicker cylinder walls and better radiators that shed the heat much faster. So yeah- focus on that cooling system next.
Your signature doesn’t have anything listed. Other than having cleaned it- what is it?


On the boost- dude- that compression ratio gives you plenty of room for boost. Is it an abnormally big inducer/ housing on that 40?

I have the electro viscous fan clutch and the Duramax plastic fan. I am also currently using the FlowKooler pump and a 190 degree thermostat. The pump may get changed to the GM unit as well. I have thermocouples in the back of both heads and they were staying right around 200 degrees, 205-208 was the highest I really saw, until a good hill and I would kick on the fan. The radiator is a stock style GM unit as far as I know. You say "designed to run at 180 degrees". Should I have a 180 degree thermostat?

My compression ratio is probably closer to 19:1 because I have the block decked .006" on both sides due to an imperfection on the deck surface. You are right that should give me plenty of boost room. If you knew my head gasket history you would probably understand why I am hesitant to "let her rip". This is also a completely different block, machined heads and MLS gaskets. So I should stop being a chicken, which I will, once I get the air charge temps cooled in some way. I think the turbo is the 16cm housing, its been long enough that I don't remember.

I drilled three holes through the fan clutch on My truck. Tapped the holes and installed three machine screws to lock the clutch solid. Thanks to Will L (iirc) for that tidbit.
Ambient temps at about 100 or more, kept the engine temp right at 200 on a long steep hill.
Previous it was running right on 217 degrees.
The electro/viscous fan system will be the next components that I will up rate to.
Thanks to AK Dieseldriver for the thread He started then posted in with the components part numbers to get the job done.

That would definitely keep things cool. I'm just not a fan of a locked fan.

That's a sharp looking rig, Andrew!! FWIW, yours would look dumb with a cap on it.

You are just tying to give me warm and fuzzies.
I have one of those sleeper like things that sits on the bed. I haven't installed it yet because I want to get the bed liner sprayed in first. I also need to figure out what type of seal to use to the cab.