Just picked up a 85' 6.2 C code Suburban

[FalcortheRooster]

Hello everybody!

First diesel here so sorry ahead of time for any dumb questions.

Couldn't Pass up the deal on this so I Bought it.

Already been through a couple of the basics:

New Batteries, Oil change, and Belts, replaced a couple fuses.


Starts up and runs great When its cold. Once it warms up and I stop, it turns over for days, no start.

Got it to start once by holding the gas open, doesn't work every time.

Smokes a ton when you do that also.

Thinking 33's or 35's for the new tires, looks like a lot of people run 3.08 gears, with the stock tranny.

Im thinking a nv4500 sounds nice, but Im planning several trips and camping excursions so any reccomendations would be welcomed!


Thanks,

Garrett

[MajMike]

Not sure about the starting issue, I'm sure someone with a lot more knowledge than I will chime in soon.

What tranny do you have now? If it's the 700R4 I wouldn't mess with it assuming it is perfectly functional. As for tires and gears, if you go with 35's you will probably need deeper gears, at least 3.42 (like mine) or possible 3.73, again others here will add their $0.02. Good luck and enjoy.

[AKMark]

I've had Suburbans with 3.42's and 31's as well as 3.73's with 31's. 3.73's were perfect for 31's. The 3.42's got better fuel mileage, but couldn't tow anything.

For 33-35's, 4.10 or 4.56's. 6.2's don't use much more fuel revving it higher going down the road and work so much better when they are closer to 2000 rpms.

I have 4.10's and 36's on my K-5, but it doesn't have an overdrive, so it equals out and moves along nicely.

Check the glow plugs. Does the glow plug light come on at all when warm? I have put a manual relay on mine. I control them. When it's warm it needs less, but sometimes these beasts need a little glow even when warm.

[AKMark]

Especially if someone has used either on them without disabling the glow plugs.

[FalcortheRooster]

Thanks for the help so far everybody!

I think the fuel source is the culprit but im going to go ahead and replace the glow plugs with some new 60g plugs.

35's with 4.10 gears? Im not going to be towing much but i want to be able to get through the mountains and hills without slowing down all of traffic behind me.

would 33's be a lot smarter for that?

Ive got the room now for either

[AKMark]

33's would be a better option. I had 285/75R16's (33's) on my 99 6.5 K2500 Burb with 4.10's and it was a beast.

The 6.2 is going to be a dog compared to almost anything else, but gearing will help. With a 700R4, if you are paying to regear, I'd go 4.56's. You'll like the pull it has versus 4.10's and you won't use much more if any fuel.

Also, I've broken 1/2 ton axles without a trailer on icy ground. I prefer the 3/4 or 1 ton axles to keep things from breaking so easily. I have a 3/4 front and rear from an 86 Suburban. If you were closer I would cut you a deal.

[joeq]

Hello everybody!
Starts up and runs great When its cold. Once it warms up and I stop, it turns over for days, no start.
Garrett

This sounds strange to me. My problems used to be the opposite. I'm also curious what would cause a "hot start" problem. Heard of it on gas engines, but not diesels. I would think it would be fuel system related.
Another welcome to the forum Garrett. Nice looking Burb. Hope you enjoy it. Keep us posted on your progress.

[Dvldog8793]

Howdy and welcome...
On the hot start issue....Glow plug control. If your glow control is saying that the engine is warm enough to start without glow plugs then you don't get them. If your wait light is not coming on or you cant hear the glow relay cycle then you are not getting glows.

My van(175,000), needs glows EVERY start. I have a bypass switch in the line that I can engage the glows any time I want. Works great, I used a momentary starter button.

My 1986 blazer(60,000) sometimes will start COLD without glows and if it has been running at it pops fast. This is good since the glow control for this rig died a tragic death and has not been updated yet

IMHO...the reason for this is compression and injection. An older engine with some miles on it has less compression and the4 injectors have a dribble instead of a spray. Both lead to hard starts.

60g's are good update, I have had good luck with the quick heats from Kenneddy as well.

Also make sure that your starting system is in good condition and that it spins over fast enough.
Hope this helps!

Good luck!