Hi. I'm new to the forum and I got a intresting issue. I got a 92 c2500 5 speed manual truck that used to have a 6.5 td but I replaced it with a 6.2 NA out of a 83 gmc c10 that was a automatic because that's the only engine I could find in my area that wasn't more than 2000 dollars. (Old motor had over 300k on it and i shattered a piston and a rod decided to try to be a hammer after getting it running, bores were severly wore) It's a lowish mile engine (40psi oil pressure hot)from what I can tell (still has most of the original orange paint on it and no evidence of a respray) that was for 300 dollars and it runs not bad. Now to the issues I have.

1. if i let it cool down completly and i go to start it, it starts up good since the 92 gp controller works awesome and it will smoke blue out the exhaust until I either let it warm up for 10 minutes or I plug in the cold idle wire (previous owner wired it up to the hot wire to the ip). Then after it warms up it starts up like a dream. Idk of this is normal or not. I do have to say this. The ip was redone in 1999 and the injectors are probably newer. They don't have much surface rust. The marks for timing are about 1/4 advanced. Haven't touched it. I am running the mechanical fuel pump on the block due to me hating electronics and wanted the redundancy so electric lift pump is deleted. Also running the 83 filter setup which are new.

2. When it's below 85 degrees outside, it drives down the road pretty good. But if it's over 90 degrees or higher ( lately it's been 104 here in kansas) it seems to have like maybe 80-70% power above 2000 rpm and I can't really go over 70ish in 5th like I can when it's dark out and cooler( then i can peg the speedo if i want to) Gotta put my foot to the floor to stay at 75 and cropdust the guy behind me. I am running the 83 air cleaner and I don't know if it's just eating hot air under the hood or what. It smokes just a hair above half throttle when it's hot out. Looks to be a grayish color (5 speed nv4500 with 3.42 gears) temp stays around 200 +-5 degrees.

3. Is it supposed to have a little rattle at idle? I've read from some other forums about it but can't get a clear answer on it. It sounds like it comes and goes every 8 seconds or so. It's hard to pin point if it's too far advanced or not. I haven't tried adjusting the timing yet due to me not wanting to mess something up due to this truck being my daily since it has ac.

4. Now the egr plate is blocked off in the intake. Is this gonna have any effect on how it runs? Just curious since i know really nothing about 6.2s (give me a sbc or big block and I can tune it up like no tommorow but a 6.2, don't know jack.

Sorry if it's a long post. I want to keep this truck in good shape drivetrain wise since my 75 k10 is in surgery for rust repair and the 400sbc torn apart for rebuild. Thank you

 

The rattle at Idle sounds like the Harmonic balancer damper and the running issues sound like the injector pump is on it's way out.