How to get my 6.2 to run more smoothly?

[chicagodiesel]

Can't say what's normal, but mine does too. I'm out of town this weekend but we should meet up and I can help you change the balancer as I've been through that one already and it's just labor intensive (fan, fan shroud, all belts, crank pulley, etc...). I pulled all my injectors and cleaned them plus advanced the timing by about a quarter inch and the vibrating is still there but way way less prevalent. I'm going to be changing the water pump in the next few weeks and will change the timing chain at that time...so maybe that will help out with having the pump so advanced. Either way, works in progress. Good luck and see you on the road sometime.

 

[wired1000]

Can't say what's normal, but mine does too. I'm out of town this weekend but we should meet up and I can help you change the balancer as I've been through that one already and it's just labor intensive (fan, fan shroud, all belts, crank pulley, etc...). I pulled all my injectors and cleaned them plus advanced the timing by about a quarter inch and the vibrating is still there but way way less prevalent. I'm going to be changing the water pump in the next few weeks and will change the timing chain at that time...so maybe that will help out with having the pump so advanced. Either way, works in progress. Good luck and see you on the road sometime.

That's somewhat comforting... anybody else want to comment on whether their front driveshaft has some play in it? And whether it's supposed to?

I would love some help changing out the balancer. I've been meaning to put new belts on too. They aren't bad... but I'd rather not have to worry about them. Glad you're making progress on yours. Hope we can meet up soon!

 

[bushhawg73]

My M1008 has play in both the front and rear driveshaft. If it is sitting on jack stands I can twist the shafts back and forth a bit. I would say anywhere from 1/16 to 1/8 of a turn. I do not see this as a problem, just normal wear in the gears, transmission and stretching of the transfer case chain. I have owned other chevys with similar drivetrain and they did it to. I just remember it is there and give it a change to catch up before I pour on the fuel. Sometimes they will make a clank sound when you put them in gear. Mine does it all the time and the rear end makes a poping sound about once a year that makes you think someone just shot a gun behind you. She still is going strong and I have changed the rear end fluid and inspected the inside of the case. All I found was verrry fine grey metal dust or shavings on the magnet, no chunks of metal.

 

[choll]

When you chicago guys meet let me know Im in Munster In. Im from vegas but will be in the area for a while for work. I drive to you to help out

Chuck

 

[wired1000]

A million thanks to SS member "ChicagoDiesel" for helping me remove and replace my harmonic balancer, as well as point out a few other things I should look at. The big one is that my rear-most passenger-side fuel injector seems to be leaking fuel.

The engine is running more smoothly, but still unevenly. The next big to-do is tighten up that injector as that would definitely explain the uneven running condition.

 

[Barrman]

Unless fuel is squirting out on every pulse, that probably isn't your rough idle problem. Yes, it should be fixed. I still think you will need a new injection pump to make it right.

 

[wired1000]

Reviving this old thread because I've done some work and gotten some results!

The loose injector: Tightened it. Nothing changed.

Cleaned fuel return "check valve". Mine, being an '86, doesn't seem to have the "glass ball" type that others have talked about. I have some pictures I'll post, but my phone camera didn't want to focus on it from close up. It basically just looks like a plastic tube. Maybe the glass ball disappeared? Anybody want to comment, based on the pictures? Anyway I put it back in and reattached the hose. Hard to tell if anything changed.

Adjusted the timing on the injector pump: Basically, I loosed those three bolts that hold it on, and it moved over about 1.5-2 millimeters towards the drivers side. I figured that was about what people had talked about moving it to, so I just tightened 'er back down. Holy crap, what a difference! Much smoother! Wish I'd done this a long time ago!

Next up is the spin-on filter mod... I've been having trouble starting her lately, and I've seen talk about that being caused by leaks in the fuel system. I also have an electric fuel pump to install!


Note, first and third picture are of the "check valve". Middle picture is the timing marks on the injection pump, post-adjustment. Pre-adjustment they were aligned perfectly.

 

[ryan77]

@chicagodiesel: where are you located? I'm in Humboldt Park.

You better armor that truck in that neighborhood!!!!

 

[chevyCUCV]

I looked a long time ago for this thread with the wum wum wum noise..
Long story short, mine had the same noise and it disappeared with the new harmonic balancer.

Keep up the good work

 

[donalloy1]

So far so good with my HB. Was going to suggest that bb's in dryer was notorious PS Pump Bracket. Just repaired mine and sounds like new vehicle! Check it out if sound is still there? Thanks to all for wealth of information here. Need to read over again and again. Not to mention Technical sources to tap into as directed. DMLII sends....

 

[WARWAG]

Ive just started to notice some wierd Harmonics going on with my engine at stop lights. A vibration that wasnt there before. I will be changing out my Harmonic balancer when I get back. Ill let you know if that was my "vibration" issue.

 

[wired1000]

The bb's in dryer sound turned out to be something related to the 4WD. I had been in 4-Hi , hubs unlocked, without realizing it. Once I disengaged the front wheels, the bb's in dryer sound stopped. I've had a lot of problems with my PS pump bracket... it's been welded, and I always check that first when I hear some sounds.

The latest thing I did, yesterday, was to replace my stock fuel filter with the Wix 24770 base and a huge freaking spin-on filter. Bunch of work, but I think it'll be worth it. I need to try the "cracking one injector at a time" trick to see if I can localize which cylinder is causing the beater-like uneven-ness. Maybe next week.