Reconditioning an old engine

[MetalheadOC]

Hi all. After months of delays, I'm FINALLY starting to move ahead with my gas-to-6.2 conversion on my '90 'burb. The donor engine is out of an '84 2wd 'burb with just shy of 100k on the clock. Steam cleaned it yesterday and verified that yes, there is in fact an engine under all the crud.

So now I've got a squeaky-clean 26 year old engine on a stand. So the question here is, what should/MUST I do to recondition it for it's new life, short of a rebuild of course? On the "for sure" list so far:

New glow plugs
Vavle cover gasket (small leak)
All guage senders & switches
Water pump
PS pump
starter
all rubber bits & hoses

Any critical items I should add here?
On the "maybe" list:

rear main seal: I plan to switch to synthetic oil once it's close to running, no leak there right now but switching an old engine to synthetic can make them pop up. From what I understand it's fairly easy & cheap to do while the engine's out of the truck

Stud girdle: worth the expense/effort, as long as I have the oil pan off for the above?

oil pump while I'm at it? (old engine died of oil starvation, now I'm a little paranoid about it)


Figured this would bea longer list actually.:rolleyes: Any upgrades I'm missing here? Also, what can I do to keep the engine in good shape until startup day? It's going to be many months yet before it's even in the truck, let alone running. I remember hearing about a trick when rebuilding a 350 to run the oil pump with a drill motor, can something like that be done with a 6.2 to keep everything oiled & prevent corrosion?

[john8662]

Skip the gaskets on the valve covers, or you'll be doing it again, and again. Use quality expensive RTV like The Right Stuff, will seal properly, same goes for the pan.

Everything else sounds good.

[NH2112]

Closely inspect the rear main sealing surface on the crank. If there's even a hint of a groove in it I'd pull the crank out and have it welded & machined to spec, since you can't get a speedy sleeve on the 2-piece seal cranks.

[MetalheadOC]

Closely inspect the rear main sealing surface on the crank. If there's even a hint of a groove in it I'd pull the crank out and have it welded & machined to spec, since you can't get a speedy sleeve on the 2-piece seal cranks.

Hmm now that's good to know. Since there is no leak at all now (far as I can tell), might it be better to just leave it alone & not fix what ain't broken?

[Robyn]

The older engines had a rope seal. The seals now come as a two piece hard backed neoprene and drop in like that on a BBC

With the engine out, Yank the pan, inspect the bearings, look over the center main webs for cracks in the areea of the outer bolt holes in the block.

No cracks is a good thing.

Yank the timing cover off and swap in a new chain.

Reseal the front cover and then reinstall the cover with a gasket and a little silicone on it.

Check the water pump and its back plate and at least install a fresh gasket.

Inpsect the vibration dampener for slipped outer ring or protruding rubber.


Get the heads off and look things over. Use a 6.5 gasket when you go back together.

Make sure that the fire rings on cylinders 1 & 2 have not worn into the deck.

Use new head bolts as these area one time through item (TTY or torque to yield)

Check the precups in the area of the fire port for cracking. No cracks allowed that cross the fire ring. (factory says 3/16 long max as far as cracks)

Look are area over between the valves for cracks.

Now, the pushods in these engines are to be installed with the copper colored ball to the rockers.

These can be hard to see but if you look closely the color will be evident.

If you screw this up, the rockers and the pushrods will fail :eek:

As mentioned, use the gooooooooood stuff silicone on the Valve covers.

You can do fine with the new felpro pan gaskets if you use silicone on both sides.

The VC's need to be set with the High temp (orange or Black) silicone.

Wipe the head surface off well with brakekleen and also the cover flange.

Goop well, set the cover on and snug the bolts (( KEY WORD is SNUG)

Once the gooooo cures (next day) snug the bolts a tad more.


The head bolts are to be torqued as per instructions.
20 ft lbs first pass, 55 ft lbs second pass through the sequence.

3rd time is 1/4 turn more (no particular reading)

These engines used select fit bearings in both the rod and main locations.

SOOOOOOOOOOoooooooooo you may find upper and lowers with different sizes.

Common is a .013mm US this is .0005" (Half thou)

You can use standards in most of these applications.

.0025" is a great fit on both rods and mains.

Spec on the rods is .0017 to .0039
Mains are about the same, But with standards you will fall in at around .002 to .003

If the engine has minimal blowby, you may not need to mess with the rings.

If the blowby was a tad much, pull the slugs out and lightly hone the block and install fresh rings.

A little bottle brush hone works great to get a nice crosshatch back.

Fresh glow plugs (60G) would be great.

Get the injectors freshened up so you wont have issues there.

If you really want to spiffy it up, take the IP in too and have it checked and at least resealed.

With near 100K the advance piston is probably worn out (in the IP)

Anyway, a 6.2 overhaul at a glance.

Missy

[suburbanK-2500HD]

Wery nice recipe :)

Btw, i guess this is a non electric pump.(advance piston)

Is there any such parts in the electronic IP, that is worth looking at, or do we just wait for the bang. :)

[MetalheadOC]

...good stuff

Missy

Wow:eek:

Lotta good info there, but way more than I'm hoping to get into. I'm just looking to a light freshening/fix any glaring weak spots, not a complete tear down. I'm still on the fence even, whether I want to pull the heads or not (since this was a good running engine before it was pulled). I guess I'll know for sure there depending on how many complete glow plugs I pull out.:D