More on 6.2 upgrades...HELP!

[hotrodelko]

OK, I'm new on here, and need all the help with my 89 'Burb that I can get. First, the background. 89 v1500 suburban 6.2, 4l60 trans, unknown gears. Everything is rock stock and it has 169k on it with no rebuild as far as I can tell. Was told the IP and trans were gone thru shortly before I bought it. Starts good cold, even when not being plugged in this winter. New mechanical lift pump and stock filter element. Now the issues...... The truck takes off great from a stop, but falls flat on it face when I'm trying to get on the freeway, and forget towing even a light trailer..... I can't run it in OD, and even then, I end up crawling up even the most gentile grades! My mileage seems low, at best.... I'm guessing in the 15-17 range if I'm lucky, and less around town. Time for new injectors? Lose my EGR intake? Which style is the best to upgrade to? The open plenum military style or the dual plane 'j' style? Turn the pump up? Also, I noticed the pump timimg mark is just to the left of the mark on the engine....slightly retarded timing? OK, enough questions for now... Anything you can throw my way would help! Glad to be a new member!

One thing I need to add........ sitting in the driveway, with the engine warmed up...(after driving).. If I take it to WOT, it blows tons of blue/white smoke and really reaks of unburned fuel.... and the exhaust smells really strong at idle as well...once again...bad injectors? I'll shut up now and wait to hear....

[john8662]

Welcome aboard!

Low power on 4x4 burb?

A couple things come to mind to pay attention to first. You mention that the IP timing is on the left of the mark (mark on IP flange towards passenger's side), that is retarded (the timing), so move it back line-to-line and see what it does.

The smoke will likely decrease.

While you're at it, you have the option of moving it slightly to the driver's side (right) and advancing the timing a bit, to compensate for timing chain stretch.

It's your choice.

Check and change the filters as applicable (fuel and air).

The EGR could be the issue, but that is usually associated with low power and BLACK smoke.

As far as the intake manifold upgrade for the near future, you'll need an open plenum intake with the single 1" CDR output nipple (not two 1/2"), but w/o fuel filter tangs on the back (interfere with engine-mounted vacuum pump). I have one of these if interested...

Set the timing and report back.

Injectors could help with the power department, but usually not a HUGE difference.

J

[hotrodelko]

Thanks for all the info. I'll try the timing this afternoon once I get home. Fuel/air filters are new as of last week, so I know that's not the prob. Would be interested in the intake, let me know what you need out of it... Should I be worried about the timing chain? I know on my old SBC that I would have probably replaced it by now.... Should I think about that? I used to work on the 6.2 a lot when I was in the military, but they didn't let us play that much and find out what they could do!

[john8662]

I don't usually see timing chains that are severly worn. But replacing it has granted some lost timing back, getting the advance.

I really don't think that is the problem here tho.

On the intake, send me a PM.

J

[Robyn]

I agree with John on the timing but I am suspect of the IP and injectors.

Too many folks will talk of pumps that were "Just Gone Through"

Hmmmm I have one of those in the pump shop right now that was "JUST GONE THROUGH"
The thing is worn out and wont even perform to specs.

I would do yourself a favor and yank all 8 of the injectors out as well as the IP and take the lot of it to a good pump shop and have the stuff tested.

If the nozzles are not up to snuff and are not working correctly and or the pump is not performing well the engine is not going to do a good job.

The little 6.2 is slightly anemic anyway and if its got IP or injector issues its just gonna drive you crazy.

Start with good IP and nozzles and then get the timing right.
Put a bar and a socket on the center crank nut up front and try to move the crank back and forth, if you get a bunch of slop when you do this you have a loose timing chain.

**NOW LISTEN UP** The crank and pistons will move easily until your pushing compression. A gentle back and forth movement on the crank will disclose a loose timing chain.
The valve train takes a fair amount to turn it over.
The gentle back and forth will a most likely result in a sudden increase in the force required to move the crank. When it gets slightly harder reverse and go the other way. Once you do this you will see what I am refering too.

If you have any appreciable amount of slop in the timing chain yank the cover and replace the chain.
The sprockets on these engines last a long time, just a new chain should get you back in the ball game.

One of the reasons the truck takes off good is the really low 1st gear in the 700R4 tranny.

Get these issues taken care of and you will find your little diesel creature to be a totally different animal.

Do as John mentioned and get the timing back up line to line when going back together.

When all is well these little engine should cackle pretty good especially when they are cold and still have a good liitle rattle when running warm.

One of the biggest issues with the IP's on these engines is the advance pistons wear out in the bore and the advance stops working right and away goes the power.

My 91 Burb is in the same boat.
It runs ok but the power is way down. Not much cackle anymore either.

Give it a go and let us know what shakes out.

Hope this helps

[DickWells]

:) Robyn: Just curious. Can't you pull the oil filler neck off and watch the end of the IP, like on my 6.5? I mean, while you're moving the crank back and forth. I've never really looked at a 6.2.
DW

[Robyn]

Yup sure can. All the same breed of cat.
I have always just felt the slack and not bothered to look.
Just my way of doing it.

Unbolt and pull out the oil filler and the rock the crank and watch the pump drive and see how much slack ther is.

A loose timing chain will really kill the power

[hotrodelko]

Hey Everyone!
Thanks for the info, still trying to fiddle with things, and scrape up the money to get the injectors gone thru...but now a bigger and more immediate problem.... I have the dash apart trying to do the d?#! heater core, and I can't seem to get hte box out to even get to it! It looks like there are pressed in bolts holding it in from the inside thru the firewall, but I can't find where they would be on the outside to remove them!!!:mad: Someone help me please! This is still my daily driver, adn with it all apart, I can't drive! THe chilton's I have is about useless in this department, as well as w/ my cruise control (doesn't work at all...go figure...).... Any help on both items would be greatly appreciated....

[HammerWerf]

Hotrodelko,

http://coloradok5.com/heatercore.shtml

This is an article I used as a help when I had to replace my heater core.

In a pinch, you could go and get a hose connector to tie the two heater hoses together. just remember, one is 5/8 inch and the other is 3/4 inch. Sometimes I see it in the big orange store, in the tubing and plastic pipe section of plumbing.

HammerWerf

[Subzilla]

You can't see the bolts from the engine side because they are under that darn black plastic cover (sound insulation?) that surrounds the a/c stuff, blower motor, etc. I used a rotary tool and very carefully cut mine in half to have access to those nuts. Yes, the heater core has got to be one of the more frustrating things to replace on these vehicles. Just be patient and do one thing at a time!

[hotrodelko]

thanks to all for the tips.... I got the thing replaced, and the truck is [I]mostly[I] back together...minus a few parts like that stupid plastic shielding. I can already hear a little more engine noise, but that's a small price to pay in my mind for being able to access those nuts at a later date if the new core goes before the rest of the truck dies! THANKS AGAIN!:cool:

[hotrodelko]

OK, I bumped the timing on the IP to just to the drivers side of the mark now(barely more than the width of the line) and I think it's doing better... although it may just be a mental thing, hoping for an improvement! How far is too far to advance it? Cruising down the freeway at 60 now barely requires any throttle... definate improvement! I guess the next test will be towing the boat up a hill.... Or even uphill empty.. The hill heading out of town used to require almost full throttle empty and usually dropping out of OD. On the injector and IP question, how much should I reasonably expect to pay to get them checked on the bench?? Money is tight (surprise there...with fuel at 3.19/gal!) adn I can't dump a ton into it, even though the Banks kit looks mighty appealing!


I agree with John on the timing but I am suspect of the IP and injectors.

Too many folks will talk of pumps that were "Just Gone Through"

Hmmmm I have one of those in the pump shop right now that was "JUST GONE THROUGH"
The thing is worn out and wont even perform to specs.

I would do yourself a favor and yank all 8 of the injectors out as well as the IP and take the lot of it to a good pump shop and have the stuff tested.

If the nozzles are not up to snuff and are not working correctly and or the pump is not performing well the engine is not going to do a good job.

The little 6.2 is slightly anemic anyway and if its got IP or injector issues its just gonna drive you crazy.

Start with good IP and nozzles and then get the timing right.
Put a bar and a socket on the center crank nut up front and try to move the crank back and forth, if you get a bunch of slop when you do this you have a loose timing chain.

**NOW LISTEN UP** The crank and pistons will move easily until your pushing compression. A gentle back and forth movement on the crank will disclose a loose timing chain.
The valve train takes a fair amount to turn it over.
The gentle back and forth will a most likely result in a sudden increase in the force required to move the crank. When it gets slightly harder reverse and go the other way. Once you do this you will see what I am refering too.

If you have any appreciable amount of slop in the timing chain yank the cover and replace the chain.
The sprockets on these engines last a long time, just a new chain should get you back in the ball game.

One of the reasons the truck takes off good is the really low 1st gear in the 700R4 tranny.

Get these issues taken care of and you will find your little diesel creature to be a totally different animal.

Do as John mentioned and get the timing back up line to line when going back together.

When all is well these little engine should cackle pretty good especially when they are cold and still have a good liitle rattle when running warm.

One of the biggest issues with the IP's on these engines is the advance pistons wear out in the bore and the advance stops working right and away goes the power.

My 91 Burb is in the same boat.
It runs ok but the power is way down. Not much cackle anymore either.

Give it a go and let us know what shakes out.

Hope this helps

[john8662]

To get the pump and injectors tested should exceed this:

Injection pump at or below $100

Injectors, from free to $20.

It's hard some times to throw money at the old truck, but then I go to the carlot and see the new ones, and their price. Then I have no problem whatsoever going to VatoZone or O'Reilly's and paying for parts...

J