6.2L Revival Questions

[burnoil]

Hey all,
I've been lurking for a bit trying to glean what I can before posting "searchable" questions. I have found that there is a bunch-o-good info around here.

Anyways, my question involves a recent acquisition. I had a military 6.2L out of a M1009 follow me home awhile back and am wondering what would be some things to do to it to get it road-ready and also prep it for a Banks turbo kit. The engine is an '86 "J" model with a bit over 30K on it and from what I can see, I believe it to be true, however, I have no idea how long it has been sitting. It has a pan gasket that is moist, some seepage around the rear main and the cam plug is a bit damp as well. Nothing terrible, but things I want to address on an engine stand as opposed to upside down, on my back when it is in the truck. Speaking of trucks, it is going to reside in a '72 K20/30 Suburban with a NV4500, NP205 and 4.10 gears. I have all the goods, just making the time to get them all talking to each other while not neglecting the family on the other side of the garage door is where the delay comes in.
So, any recommendations on my revival?? I'm not looking to back a dump truck full of money up to it and start shoveling, but want to address anything that might be or is a common issue with these motors prior to hitting the road. The main questions that I have are things like o.e. head gasket quality, injector/pump issues from sitting etc, head and main studs/main girdles worthiness,or anything else not listed here that you know of.
Any opinions would be appreciated.
Thanks!!

[john8662]

Welcome aboard!

I love it when engines follow me home ;)

With a low-mileage 6.2 you could just address the usual things on the stand before deploying it in the chassis.

I'd probably leave the heads and gaskets alone with that mileage, but, why was the engine pulled?

The Pan will need to come off so you can inspect some things. Inspect the main webbing for cracks, if none are found you've got something great on your hands. Then, by all means, install the stud-girdle kit to help protect the bottom end, especially since you're planning some kind of turbocharging the future.

While the pan is still off, replace the rear main seal, it'll probably have the rope seal, so go ahead and install the Fel-pro seal. You'll need the seal, some of the purple/red anerobic sealant and the rear pan seal (rubber). For the pan gasket, you'll just use RTV, I highly recommend "The Right Stuff" RTV sealant.

I sure hope the cam plug isn't leaking, but you can fix it on stand too, with a little finess, post back if that's leaking.

Sounds like a neat project, I don't see many 72 Suburbans, well Suburbans in that body style that is.

Cool.

J

[Robyn]

Welcome to the forum

Good info from John 8662

I would however go a little further, I would yank the heads off only after steaming the sucker off well.
Plug off any access points to the engines innards and wash it good.
With the heads off you can get a good look at the cylinder walls and make sure there are no issues with pistons or such.

Simply roll the engine over and look at each and every cylinder, and also look over the tops of the pistons.
With the heads off you can check them for cracks in the firedeck and also see what condition the gaskets were in.

Installing an engine, while not really tough is a lot of work and to find an issue after it in the truck just SUCKS.

Yank off the front cover and check the timing chain. The chains tend to get loose in these engines and a replacement is cheap and its easy while the engine is out.
A new seal up front is a must.

Remove the pan and roll the little beast over on the stand and have a look at the bottom end bearings.

You need to number stamp the rod caps and rods at the part line on the pan rail side so when you remove them to have a look see you can get them back on correctly as they are not numbered from the factory.

The main caps have numbers cast into them so they are good to go.

If the bearings show much wear a new set can be rolled in with no bother.
A fresh rear main seal can also be done at this time.

The rear cam plug seepage can be easily fixed with some JB weld applied around the plug where it contacts the bore,
Clean well and wash off with brakekleen and dry good, Apply the JB weld to the area and let harden undisturbed over night.

If this is a newer engine with the stamped steel rocker arms a new set of rocker guide buttons is a great idea. these are plastic and can break causing things you dont want to hear about to happen. They are cheap and easy to replace.
Once the little sucker is back together apply a couple rattle cans of paint and your off to the rodeo.

Your little beasy may very well ned little but a good look see on a used engine is always a good idea.

I you dont yank the pistons out the rings should be fine.

Be very careful to keep things clean insdie while you clean off the cylinder deck surface. You can hand scrape the gasket remains off but stuff some rags into the lifter area to keep the crud out.

Enjoy and keep us posted

Robyn

[burnoil]

I'd probably leave the heads and gaskets alone with that mileage, but, why was the engine pulled?

The engine was pulled because the Blazer that held said engine came off a car trailer at 75mph and proceded to do "cartwheels of joy" with its new-found freedom. Truck was pretty much just damaged goods at that time, but the motor etc survived pretty much unscathed.

What are the head gaskets made of on these motors?? Steel shim or composite??




I sure hope the cam plug isn't leaking, but you can fix it on stand too, with a little finess, post back if that's leaking.

Bah, I wouldn't say it is leaking, but it has what I would classify as "greater than normal seepage". Doing it on the stand would probably be a hoot, but doing it on the hook shouldn't be too bad.



While the pan is still off, replace the rear main seal, it'll probably have the rope seal, so go ahead and install the Fel-pro seal.

Do these usually come out intact, or do they leave remnants behind?? I'm kinda hoping that by pulling the main caps and hopefully finding absolutely gorgeous bearings, that I can get the old one out and roll the new one in. Feasible or do the rope remnants require direct access scraping??



Sounds like a neat project, I don't see many 72 Suburbans, well Suburbans in that body style that is.

Cool.

J

Yeah, the body style is what is keeping it in the driveway. A 5.9L Cummins with a full Banks kit followed me home about 3yrs ago and was going to get installed in the Sub, but time being relatively unavailable, and the amount of serious modifications necessary to pull it off, it sits untouched. I actually had the Sub traded to a friend for a full-on loaded '90 V2500 Suburban, but I was having withdrawals before it left, so I decided to go the 6.2L route being that I had already converted it to a big-block previously.

Any thoughts on the injection pump/injectors?? I would assume there would be some sort of funk in it/them from sitting, but I'm not too familiar with these components (as opposed to Cummins components).

Thanks for all the info!!

[burnoil]

Welcome to the forum

Thank you!


Good info from John 8662

Definitely.


I would however go a little further, I would yank the heads off only after steaming the sucker off well.

Believe it or not, other than the seepage, the only thing on this motor is dust!! Normally I would pressure wash the hell out of it, but I think a garden hose and some mild cleaner/degreaser will make this thing showroom fresh.


With the heads off you can get a good look at the cylinder walls and make sure there are no issues with pistons or such.

I'm really hoping(!!) not to have to pull the heads. I was thinking of inspecting the bores as best-as-possible from the underside and deciding from there whether head removal will be absolutely necessary.



With the heads off you can check them for cracks in the firedeck.

Is this a pretty common issue??


Installing an engine, while not really tough is a lot of work and to find an issue after it in the truck just SUCKS.

Oh boy, I could regail you with stories (unfrtunately more than a couple) about my DD that pulling the engine out of IS tough and how true the statement about problems afterwards really is. Comparatively, with these old trucks, I could do one standing on my head with one hand behind my back, but, this will be a family wheeling rig, so I'm trying to head off the problems before they ruin a weekend or more.


Yank off the front cover and check the timing chain. The chains tend to get loose in these engines and a replacement is cheap and its easy while the engine is out.

Ahhh, thanks for bringing this up. I have read that any timing chain in these motors is basically a hand grenade without a pin and the only way to go is gear drive. Is this really true or will a quality brand (Cloyes etc) suffice??



If this is a newer engine with the stamped steel rocker arms a new set of rocker guide buttons is a great idea. these are plastic and can break causing things you dont want to hear about to happen. They are cheap and easy to replace.


What classifies it as a newer or older engine?? If it has the stamped rockers would something else be preferred??

Thanks a bunch for the info!!

[john8662]

The engine was pulled because the Blazer that held said engine came off a car trailer at 75mph and proceded to do "cartwheels of joy" with its new-found freedom. Truck was pretty much just damaged goods at that time, but the motor etc survived pretty much unscathed.

What are the head gaskets made of on these motors?? Steel shim or composite??

Composite Gaskets, with an '86 Model, it's got some decent gaskets from the factory, no realy worries here. Sounds like the engine will be just fine to me.





Bah, I wouldn't say it is leaking, but it has what I would classify as "greater than normal seepage". Doing it on the stand would probably be a hoot, but doing it on the hook shouldn't be too bad.

The only reason I'm reluctant to mess with the cam plug on an assembled engine is because the rear cam plug is what sets the camshaft end play. A trick I think will get you by should you decide to remove the plug (that will be fun with the cam inside) will be to get the new plug and tweak it a bit. That is, this plug is the same as a Big Block gasser, but, the way the plug is made it is bulged inward into the engine. So, take a flat surface and level it out first (no more bulge), then install this plug in the block the same depth as the original plug, shouldn't trap the cam this way. Be sure to use a good sealant for assembly though, like an Anerobic sealant, or the Brown "Aircraft" sealant, don't use regular RTV.




Do these usually come out intact, or do they leave remnants behind?? I'm kinda hoping that by pulling the main caps and hopefully finding absolutely gorgeous bearings, that I can get the old one out and roll the new one in. Feasible or do the rope remnants require direct access scraping??


The rear main seal is a snap, the rope seal will come out in one piece and there will be little-to-no residue left behind. Just wash out the bore a little with some brake cleaner and blow it out with shop air and you're set to install the new seal and then the cap. Pay special attention to the instructions that come with the seal.



Any thoughts on the injection pump/injectors?? I would assume there would be some sort of funk in it/them from sitting, but I'm not too familiar with these components (as opposed to Cummins components).

No problems here as well. There will be some air in the system from the engine swap, etc. As long as you take care to keep contaminants out of the fuel system during the swap (post fuel filter) then you shouldn't have trouble. If you do, then a simple pump replacement or injector renewal will be in order, which can be done simply in chassis. With 30k, the injectors will be perfect, the pump should work fine too.

To answer one of the questions that Robyn presented...

Early or Later 6.2? In 85 GM updated the rocker arm/assemblies to a stamped-steel type, so your 86 will have these inside already. The previous assembles were condemed because of a few breakages, Mainly in early 82 models, primarily due to the clips around the anchors to the heads (full "0" verses a "C").

J