Opinions on 6.2 diesel

[evoLnivleK]

Originally Posted by meatwagon83

I just bought a 88 k30 with a fresh 6.2 and a 4 speed in it, it's getting a turbo and an nv4500, I'm not sure what gears are in it yet, the spid just denotes "standard gearing"

Meatwagon, if that 4 speed comes up for sale, I would love to grab it. I'm in Ohio as well.

My turbo is mounted and I'm working on all the ancillary stuff now. I had to take a "quick" break and do a timing chain on my Toyota, but I'll be back at it tomorrow. That turbo manifold got all of Carlin's 7 dirty words during its install.

[44th Miss Inf]

Originally Posted by meatwagon83

I just bought a 88 k30 with a fresh 6.2 and a 4 speed in it, it's getting a turbo and an nv4500, I'm not sure what gears are in it yet, the spid just denotes "standard gearing"

I believe the “standard gear ratio” (rpo GQ1) for the 6.2 in a 1 ton was 4.10

[rick1956]

I was working as the lube guy at a Pontiac/Buick/GMC dealership in the 80's. There was a customer that brought his rig in because it was 'knocking a little worse than usual' or something similar, but seemed to run just fine. Turns out the crankshaft was broken into two pieces, but were still interlocked somewhat!
I thought that was an interesting testimonial of sorts.

[62 Longbed]

I've heard of things like this happening before . I guess its recommended to keep an eye on the harmonic balancer on the 6.2 engine , but also recommended to replace if not sure and to prevent possible damage . I guess to just to be safe ...

[Bob Q]

I’ve had my ‘83 6.2L for about 13 years now and my dad has had his ‘84 6.2L for about 12 years. Both have been good, reliable engines. Some complain they don’t start well in cold weather, but we haven’t had a problem. Just like anything else, you have to maintain them. Keep good glow plugs and a correctly functioning glow controller in them and they start easily.

[hatzie]

If you intend to put any serious miles or years on a 6.2 or 6.5 diesel it isn't a bad idea to put a Fluidamper on them.
The damped pulleys on engines equipped with them bear watching too.

[44th Miss Inf]

GM stuff is still available reasonably priced. This will be the second balancer, and first new serpentine pully since 83. I’ve know the truck since day one. I swapped it to serpentine in about 2000 when my best friend still had the truck. the 6.5 in my 93 busted the block, so we used everything off of it to put on this truck.

[Willowrun]

Originally Posted by Bob Q

I’ve had my ‘83 6.2L for about 13 years now and my dad has had his ‘84 6.2L for about 12 years. Both have been good, reliable engines. Some complain they don’t start well in cold weather, but we haven’t had a problem. Just like anything else, you have to maintain them. Keep good glow plugs and a correctly functioning glow controller in them and they start easily.

What glow plugs do you like? I swapped out the originals in my '93 G30 with some from an ebay source and I'm wishing I would have kept the old ones in it. It used to miss on 1 or 2 cylinders for a few seconds at start up but now it's 3 or 4 since the glow plug change.

[44th Miss Inf]

Originally Posted by Willowrun

What glow plugs do you like? I swapped out the originals in my '93 G30 with some from an ebay source and I'm wishing I would have kept the old ones in it. It used to miss on 1 or 2 cylinders for a few seconds at start up but now it's 3 or 4 since the glow plug change.

I only use Delco 60G glow plugs. I added a resistor for longer glow time though as they take longer to heat, but are self limiting (will not burn out / swell like most others)

[Bob Q]

Originally Posted by 44th Miss Inf

I only use Delco 60G glow plugs. I added a resistor for longer glow time though as they take longer to heat, but are self limiting (will not burn out / swell like most others)

I’ve had good luck with the 60G’s as well.

[hatzie]

The AC Delco 60G PTC glow plugs are the way to go.

I've been through three serpentine pulleys.

[Willowrun]

I'll go back to the AC's then. Thanks for the input.

Interested in the resistor mod. I'm still counting on the factory controller to heat the plugs but every so often I feel it doesn't know what it should do and it creates a hard start. This typically happens if it has been run and then shut down for about an hour. It doesn't know if it should heat the glow plugs or not so it just flashes them on when it really needs more glow than that. I know people wire in manual buttons but that seems so intrusive.

As a side note, in my opinion, the military 24v starting system works much better than the 12v dual battery civvy versions. It seemed my M1009 Blazers always started quickly while this van has always had a slower spinning starter causing slower starts. Anyone else experience that?

And just to add my thoughts on 6.2's again, I love them. They are just as peppy as a factory small block from the same era in my opinion.

[hatzie]

Pinout of the later glow controllers with the Metripak plug;

1. Not Used should have Metripak cavity plug
2. Cranking engine glow inhibit wire. To starter solenoid CRANK stud
3. Glow plug current sense or timer? I wired my 1976 to the glow plug output stud on the controller. It's actually spliced into the glow controller end of the LH glow plugs fusible links in stock configuration.
4. Warm engine glow inhibit. Tees into the injection pump Cold Start Advance wire
5. Engine ground

When Terminal D gets 12v ignition power the relay thinks cold start is enabled and the warm engine inhibit is defeated.

You can extend the glow time by installing one 5Ω 2W resistor in the wire running to the glow plug current sense Terminal C.

Two 10Ω 1W resistors in parallel would carry 2W current with a resistance of 5Ω
Four 20Ω 1/2W resistors in parallel would carry 2W with 5Ω resistance.
This is a fairly decent explanation of parallel resistors. https://www.omnicalculator.com/physi...rallel-formula

[1972K20]

Originally Posted by hatzie

Pinout of the later glow controllers with the Metripak plug;

1. Not Used should have Metripak cavity plug
2. Cranking engine glow inhibit wire. To starter solenoid CRANK stud
3. Glow plug current sense or timer? I wired my 1976 to the glow plug output stud on the controller. It's actually spliced into the glow controller end of the LH glow plugs fusible links in stock configuration.
4. Warm engine glow inhibit. Tees into the injection pump Cold Start Advance wire
5. Engine ground

When Terminal D gets 12v ignition power the relay thinks cold start is enabled and the warm engine inhibit is defeated.

You can extend the glow time by installing one 5Ω 2W resistor in the wire running to the glow plug current sense Terminal C.

Two 10Ω 1W resistors in parallel would carry 2W current with a resistance of 5Ω
Four 20Ω 1/2W resistors in parallel would carry 2W with 5Ω resistance.
This is a fairly decent explanation of parallel resistors. https://www.omnicalculator.com/physi...rallel-formula

Occasionally, my glow plugs will not cycle when the engine is warm, but it causes a slow/hard start.

[Willowrun]

Originally Posted by hatzie

Pinout of the later glow controllers with the Metripak plug;

1. Not Used should have Metripak cavity plug
2. Cranking engine glow inhibit wire. To starter solenoid CRANK stud
3. Glow plug current sense or timer? I wired my 1976 to the glow plug output stud on the controller. It's actually spliced into the glow controller end of the LH glow plugs fusible links in stock configuration.
4. Warm engine glow inhibit. Tees into the injection pump Cold Start Advance wire
5. Engine ground

When Terminal D gets 12v ignition power the relay thinks cold start is enabled and the warm engine inhibit is defeated.


You can extend the glow time by installing one 5Ω 2W resistor in the wire running to the glow plug current sense Terminal C.

Two 10Ω 1W resistors in parallel would carry 2W current with a resistance of 5Ω
Four 20Ω 1/2W resistors in parallel would carry 2W with 5Ω resistance.
This is a fairly decent explanation of parallel resistors. https://www.omnicalculator.com/physi...rallel-formula

Between this and my '05 Silverado "tighten gas cap" code I'm starting to think I'd be much better off flying you here to work your multimeter magic on these heaps. LOL.

I have the van at my house currently and I ordered some new glow plugs a few days ago. Probably be lazy and start with those. Then I'll google Metripak so I can figure out what I'm looking for and go from there.

Thanks!

[hatzie]

Originally Posted by 1972K20

Occasionally, my glow plugs will not cycle when the engine is warm, but it causes a slow/hard start.

Tee the glow plug contactor terminal C wire into the injection pump cutoff solenoid wire instead of the cold start advance wire.

Originally Posted by Willowrun

Between this and my '05 Silverado "tighten gas cap" code I'm starting to think I'd be much better off flying you here to work your multimeter magic on these heaps. LOL.

I have the van at my house currently and I ordered some new glow plugs a few days ago. Probably be lazy and start with those. Then I'll google Metripak so I can figure out what I'm looking for and go from there.

Thanks!

The urban myth that EVAP codes can be fixed by fiddling with the gas cap.
I've gotten an EVAP code on the way to the parts store when I dropped the gas cap down a storm drain but I've never fixed one by replacing or tightening the cap when the cap was present. Not impossible to fix it with a filler cap but very improbable.

The 5 Position Metripak plug likely looks something like this only with wires. It may be Gray or some other color too. It's plugged into the glow plug contactor/relay

You can see the cavity ID letters in the pictures posted below. A will have a cavity plug with no wire.

**EDIT Removed the pull to seat six position female terminal plug image that was just kinda close to what you're looking for.** See the next post for the actual correct female terminal Metripak 280 five position push to seat plug.

[44th Miss Inf]

PN for the 85-93 glow plug relay connector is 12101871 and is a female version of the one Hatzie shows (no disrespect Hatzie, was piddling with mine and snapped a few pictures)

[hatzie]

Originally Posted by 44th Miss Inf

PN for the 85-93 glow plug relay connector is 12101871 and is a female version of the one Hatzie shows (no disrespect Hatzie, was piddling with mine and snapped a few pictures)

My pic was only barely the same family. Pull to seat female plug rather than the correct push to seat plug and the plastic connector shell is female for the glow plug relay not just the terminals. They take the same female terminals but the plastic housings are specific to the sensor or component you're plugging into.

Thanks for posting those pictures.

The part number you posted is for the Metripak 280 repair pigtail. 12101871 is equivalent to Delco PT262
https://www.summitracing.com/parts/ado-pt262

The part number for the raw empty Metripak 280 Female terminal connector is in the GM wiring diagrams. Delphi Packard 12015982
https://www.mouser.com/ProductDetail...Ew0re52Q%3D%3D

[Willowrun]

Thanks guys...I'm getting smarter with what you're posting.
Once I put the plugs in I'll look at the resistor mod and try to figure out what that entails. I know what I'm looking for now but will need to plan out how to install the resistor(s) cleanly next. I've had several 24V military 6.2's and must have gotten spoiled with the fast starts those systems give. This 12V system seems adequate at best so hoping this will help.