Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1 (Edited)
my old work truck is super reliable in the cold, if a bit slow. It has the 350 tbi backed by a np465 4 speed and 4.10 gears in rearend. The problem is in the heat. Anytime it is over 90 degrees F,omegle it will hot stall and leave me stranded until it cools down. xender Acts like an ignition coil bad. Changed coil, cap, rotor, coolant sensor, and more. Still it remains. Thinking of swapping in a ls with a new fuel pump for discord more power and better reliability. What parts will I need to adapt an ls to the 465. I know motor mounts and exhaust manifolds and the whole wiring harness from an ls. Anyone have experience with a ck ls swap?
 

·
Registered
Joined
·
461 Posts
my old work truck is super reliable in the cold, if a bit slow. It has the 350 tbi backed by a np465 4 speed and 4.10 gears in rearend. The problem is in the heat. Anytime it is over 90 degrees F, it will hot stall and leave me stranded until it cools down. Acts like an ignition coil bad. Changed coil, cap, rotor, coolant sensor, and more. Still it remains. Thinking of swapping in a ls with a new fuel pump for more power and better reliability. What parts will I need to adapt an ls to the 465. I know motor mounts and exhaust manifolds and the whole wiring harness from an ls. Anyone have experience with a ck ls swap?
It can be a nightmare if you aren't familiar with the wiring required and the actual morphing of the powertrain into a somewhat older vehicle without all the computers and sensors.

That said: "Hot stalling" is never from a bad coil, bad plugs or caps nor rotors. They produce MISSING, not power loss.

Fuel pressure can however be a big problem. Retarded timing can be a problem, but I just KNOW you checked that - right?

Fuel filter, fuel pump (and these are really really sensitive for the correct pressure - this I know well!) can each/both contribute to loss of power at higher temps.

You need a very accurate fuel pressure testing system - for both pressure and fuel flow capacity. If you don't do that, you're wasting your time without a full diagnosis.

I've had this system fail to run well with just ONE pound of pressure off the mark!
 

·
Registered
Joined
·
3 Posts
my old work truck is super reliable in the cold, if a bit slow. It has the 350 tbi backed by a np465 4 speed and 4.10 gears in rearend. The problem is in the heat. Anytime it is over 90 degrees F,omegle it will hot stall and leave me stranded until it cools down. xender Acts like an ignition coil bad. Changed coil, cap, rotor, coolant sensor, and more. Still it remains. Thinking of swapping in a ls with a new fuel pump for discord more power and better reliability. What parts will I need to adapt an ls to the 465. I know motor mounts and exhaust manifolds and the whole wiring harness from an ls. Anyone have experience with a ck ls swap?
Older GM tbi trucks used a ignition control module that is inside the distributor. You mentioned you changed cap and rotor. The ignition control module is the box under the rotor that has 2 electrical plugs attached to it. The ignition control module has a coating of dielectric grease on the metal base to insulate it from heat. As the grease wears out the ignition control module overheats and shuts the truck down. Once the truck cools off, it starts right back up. If it is the original ignition control module, it maybe most likely going bad due to the heat getting to it over the years. When replacing the module, you must apply a coating of dielectric grease on the metal base. Your truck should run fine then since you have replaced all other parts, but you did not mention replacing the module.

This is a site for newer GM Mid Size SUVs GMT360/370 forum. I have seen the problem you have described, a engine swap shouldn't be needed, unless you just want to spend money and do a lot of extra work.
 

·
Registered
Joined
·
461 Posts
The mistake people continue to make is thinking that the paste between the D-1906/19180771 module and the distributor is dielectric paste.

It is not.

It is a thermal conductive "bedding paste" that carries the heat generated by the module to the aluminum distributor housing. This thermal bedding paste assists in removing the heat the module normally creates.

Using dielectric paste actually insulates the module from the distributor, causing it to overheat and THEN it can thermally fail.

Dielectric paste should only be used at service connections (spark plug boots, coil towers, distributor caps, battery terminals, lightbulb basses, Molex connectors, Weatherking Connectors, etc) and assorted electrical junctions as it not only insures that corrosion is abated, but that a non sparking and overheated condition that might result from momentary losses of power, might happen.
  • I was introduced to dielectric paste at a trucking company I was working at that had a number of citations for semitrailer lights blinking while being towed down the highway. Once I started putting the paste in the electrical quick-connections.... no more blinking.
GM had warnings about using dielectric grease on their HEI distributor modules, and it was printed on a small slip of paper inside the box the new modules arrived in.... but most people don't read instructions. GM even provided small tubes of thermal seating paste in the same box.

FUN FACT ---> FORD couldn't get their DY1284/LX226T modules mounted on the side of their distributors to live past the 30 day factory warranty... what with all the heat they generated .... and so, Ford offered ... at a high cost to the owner.... a conversion kit that relocated the module onto the driver's inner front fender to help keep it cooler.
(NOT the DY 893/LX203 DuraSpark System)
I just l-o-v-e Ford engineering.
Mo' money! Mo' money!
 

·
Registered
Joined
·
3 Posts
The mistake people continue to make is thinking that the paste between the D-1906/19180771 module and the distributor is dielectric paste.

It is not.

It is a thermal conductive "bedding paste" that carries the heat generated by the module to the aluminum distributor housing. This thermal bedding paste assists in removing the heat the module normally creates.

Using dielectric paste actually insulates the module from the distributor, causing it to overheat and THEN it can thermally fail.

Dielectric paste should only be used at service connections (spark plug boots, coil towers, distributor caps, battery terminals, lightbulb basses, Molex connectors, Weatherking Connectors, etc) and assorted electrical junctions as it not only insures that corrosion is abated, but that a non sparking and overheated condition that might result from momentary losses of power, might happen.
  • I was introduced to dielectric paste at a trucking company I was working at that had a number of citations for semitrailer lights blinking while being towed down the highway. Once I started putting the paste in the electrical quick-connections.... no more blinking.
GM had warnings about using dielectric grease on their HEI distributor modules, and it was printed on a small slip of paper inside the box the new modules arrived in.... but most people don't read instructions. GM even provided small tubes of thermal seating paste in the same box.

FUN FACT ---> FORD couldn't get their DY1284/LX226T modules mounted on the side of their distributors to live past the 30 day factory warranty... what with all the heat they generated .... and so, Ford offered ... at a high cost to the owner.... a conversion kit that relocated the module onto the driver's inner front fender to help keep it cooler.
(NOT the DY 893/LX203 DuraSpark System)
I just l-o-v-e Ford engineering.
Mo' money! Mo' money!

You are correct, it is a white paste, I had always heard it called dielectric grease, but yes a new module came with a small packet of it.
 
1 - 6 of 6 Posts
Top