new guy with 6.2

[198662T]

Help !! I am a new owner of a 1982 6.2 project. I have about 2 dozen questions. My project is a 1986 crew cab. I have 3.73 gears in the corp 14 and dana 60.Added 4 wheel disc brakes. It will be a TH-400 from my other truck. I have had the motor appart to reseal it. I had the injection pump gone through and turned all the way up. The injectors were overhauled and all new tips installed.I have added a turbo set up from a 1994 6.5. The turbo is a fresh GM3 unit. I intend to add an intercooler before it hits the street.
What should I expect from this? All my experience is in gas motors.I would like to find a kink free down pipe for this and I am making a 4 inch exhaust for it.I currently have a waste gate actuator from the GM4 set up on it but was told from a local shop to not use a waste gate actuator because of the intercooler as boost will not get above 8 lbs. , is this true? Budget is getting tight as the truck is in 1000 pieces.(frame off resto)I have added a Carter electric fuel pump and removed the mechanical pump and pushrod as the oil return for the turbo uses that location. Before I started all this I ran the motor and had 20 psi oil pressure hot idle and 50 psi at about 1/3 throttle. Is this good? I believe it is according to the shop manual.
I measured the timing chain and it had .580 slack in it so I left it in place. The book said to discard at .800 slack,seems like a lot to me.
I have more questions later as I am about to bring this beask back to life this week (I hope),what should I set the timing at once it is running? Thanks,Scott.

[ueckebes]

hello friend,welcome to the world of 6.2 engines,i think you will be happy. first off youre oil pressure sounds good,second go ahead and replace the timeing chain while youre tore down. third check for clearance issues on the injectors and your 6.5 turbo setup,92 and up 6.5,6.2 engines had a slightly different angle on there injectors,versus the earlier engine models,youre injector lines when in place,may not clear the turbo side of the exhaust system.not positive but i think so! soon others will chime in,somtimes weekends are a little slow on postings..

[198662T]

Originally posted by jimmie:
hello friend,welcome to the world of 6.2 engines,i think you will be happy. first off youre oil pressure sounds good,second go ahead and replace the timeing chain while youre tore down. third check for clearance issues on the injectors and your 6.5 turbo setup,92 and up 6.5,6.2 engines had a slightly different angle on there injectors,versus the earlier engine models,youre injector lines when in place,may not clear the turbo side of the exhaust system.not positive but i think so! soon others will chime in,somtimes weekends are a little slow on postings..

[198662T]

Hey thanks for the reply !! I have already put the motor back together and I do have 1 injector line touching the right exhaust manifold. I wrapped the manifold with the exhaust wrap from Summit as i have used it in the past with great results especially on a hot running gas motor. Thanks. smile.gif

[CleviteKid]

What should I expect from this?

* A heap of torque and some spinning tires.


All my experience is in gas motors.I would like to find a kink free down pipe for this and I am making a 4 inch exhaust for it.I currently have a waste gate actuator from the GM4 set up on it but was told from a local shop to not use a waste gate actuator because of the intercooler as boost will not get above 8 lbs. , is this true?

* As too many people know, I am not up to speed on turbos, but the intercooler should not prevent you from making boost. Does the local shop want you to keep the waste gate closed all the time? That could be a recipe for a blown engine if the boost climbs over 15 psi for too long a time.


Budget is getting tight as the truck is in 1000 pieces.(frame off resto)I have added a Carter electric fuel pump and removed the mechanical pump and pushrod as the oil return for the turbo uses that location. Before I started all this I ran the motor and had 20 psi oil pressure hot idle and 50 psi at about 1/3 throttle. Is this good? I believe it is according to the shop manual.

* This is excellent oil pressure. But do you believe the crummy GM gauge ? I have a good mechanical gauge under the hood, in parallel with the stock gauge, to keep GM honest.


I measured the timing chain and it had .580 slack in it so I left it in place. The book said to discard at .800 slack,seems like a lot to me.

* Too bad your engine is already back together. If you were not gonna put more than 50,000 miles on this engine yourself, then a new timing set for about $60 would have been a good investment. If you are gonna keep this engine "forever" then you will be putting the gear drive in sooner or later.


I have more questions later as I am about to bring this beask back to life this week (I hope),what should I set the timing at once it is running?

* First question, who is setting the timing, or how are you doing it? A good diesel shop with a diesel timing detector will know to set it to a few degrees before top dead center. You can time it yourself "by ear": if it sounds like a PowerStroke you have too much advance - if it is pretty quiet you don't have enough. Try to find another nearby dieselholic to help if you are gonna go this route.

We all look forward to reading more about your project.

Dr. Lee :cool:

[CleviteKid]

You can also GENTLY bend that injector line so it is not touching the manifold. It will wear, chafe, and eventually fatigue crack if you do not get it away from the manifold.

Dr. Lee :cool:

[198662T]

Thanks for the reply.The oil pressure was measured with my mechanical gauge not the dash unit.Yes they did suggest to hold the waste gate closed. Good/bad ???
I want to install boost and temp gauges. Where do I install the exhaust temp gauge,right at the turbo outlet at the top of the down pipe? I was thinking this to keep the temp probe down stream to avoid a swallowed tip as on my friends truck.

[CleviteKid]

The turbo has a waste-gate on it because it was sized to produce boost at lower engine rpm and gas flow. The waste-gate is intended to open at high rp and high gas flow to keep the turbine from overspeeding (and grenading) and to keep the compressor from overboosting the intake pressure.

So I would encourage you to NOT wire the wastegate closed, particularly if any one else might drive your truck in an emergency, or for any other reason.

The advertisers on TheDieselPage.com have pyrometers for measuring EGT (exhaust gas temperature) that are calibrated for installation after the turbocharger. I have not heard of any of our members who have thermocouples mounted between the cylinder heads and the turbo having a problem, but if you put it where you suggest, that probability drops to zero. Go for it.

Dr. Lee :cool: