Hey, I bought this motor about 10 months ago and had it stored in my garage. It's from a 99 camaro that had 171k. It ran fine before I bought it and the seller pulled it. I went to put a new oil pan / t-chain / oil pump on it today and the crank will not rotate by hand. It turns about 40 degrees and then completely stops.

-Spark plugs are out
-T chain is off, cam spins perfect
-Oil pan is off and I can see cross hatchlings on the cyl walls where to pistons are up in the
sleeves
-rocker arms are off (replaced trunion bearings)
-flywheel is not hitting anything on the stand.

 

My guess would be that water got into an.open.cylinder while sitting and started to rust up a cylinder. I have seen it on a couple engines before.

 

yeah that happen to a 5.3 and 4.8 of mine, i put the flex plate on and used a flat pry bar while the engine was on the stand, i used the attachment points of the stand to rest the pry bar on with the flat end in the teeth of the flex plate.. that's with heads off and the cylinders oiled down .. just worked it clock wise a little and then counter clock wise.. back and forth until everything was freed up, but still on the 4.8 it messed up a ring !

but the 5.3 got away with it with out hurting anything, besides the cylinder walls though, they were pitted BAD

iv got a video of it.. just not edited up yet .

yep i so thought there was something in the engine or inside the block that was stopping it.. ha then finally figured it out, it was the camshaft retaining plate bolt in the holes, that is if you took the plate off and just happened to thread the bolts in with out the plate on a bit too far i did that once hahah... the engine turned a little until the crankshaft came around and hit on the bolt lol ..

hopefully its something simple like that for you Rvn2svn .. peace

 

Similar to 404. My father in law had a boat motor not rotate. We shot a bunch of PB blaster in and pried on it. Rotated it a bunch by hand until it felt ok, and that sucker actually ran.

 

Possible its just a piece of carbon in one of the cylinders.

 

Ok, my guess was probably a little corrosion on the cyl walls. I wish I had a scope or something to see in the cylinders. I thought about just using a screwdriver in the flywheel teeth and prying on the arm of the engine stand to get it unstuck and see how far it will rotate counter clockwise.

Thank you guys

 

Ok the motor is rotating a little better. Maybe 270 degrees total. It really starts to slow down / bind when the piston skirt gets down to where the cross hatching stops and the brown / rust begins... I can feel it pretty easy with my finger... Time to hone right?

 

theres no good way to fix this besides taking it completely apart right? Scotch brite / steel wool isn't going to give a good finish and will probably just get a punch of metal dust on the cylinder walls. I'm betting that will destroy the rings and scratch up the walls pretty bad....

I'm not too confident trying to hone this motor by myself. It's the older 99 block and from what I'm reading there isn't hardly any room to open the bores. I thought about forged pistons, but if i do that I may as well get cheap aftermarket rods / new bearings / head gaskets / lifters. I can't afford that. And I definitely won't be able to afford shipping the block and whatever it'll cost to have it machined.

This sucks. I guess I'll start saving and finish this up next spring.

 

That there at the bottom of your cylinder walls is carbon build up more than likely can't tell too well from the pic, but.. also your pistons nor rings never even touch that part of the cylinder walls..

If it were me, id so take some main caps off have a look at the bearings, maybe you have spun or seized main bearings, which is keeping it from turning maybe even rod bearings..

happen to me before.. not rod bearings, but mains!

Now if you have no spun or seized bearings, then id move on to taking the heads off, to have a look at the upper part of your cylinder walls to see if they have rusted.. if so, and the pitting isn't too bad, do some light honing either type of hone will work..

I like the dingle berry type, they cost lots though, but the 3 bar type of hone will help to keep your cylinders in round, either way, just do a light hone then recheck for pitting..

you can do the above in any order, heads off first if you want either way..

also id reuse the rings, head bolts, main bolts and rod bolts but that's me
im cheap lol .. head bolts are really cheap though too so.. might as well pop out 30 or so bucks for some.. 19.97 a side http://www.summitracing.com/parts/fel-es72173

Though saving up and doing it the right way is always best ..

I have no engine machine shop in my area either.. and shipping COSTS BIG TIME.. so iv been doing it myself lol in the backyard haha.. it does work though.. Anyways i just wanted to give you some encouragement

 

You can reuse most of that but NEVER the stock head bolts. I don't care how cheap you want to be, it's cheap insurance against a blown head gasket or jacked up threads. Other bolts can be reused.

Flywheel to crank
Head bolts
crank pulley to crank

All one time use, tty.

 

Don't reuse the head bolts. They stretch during install, so if you go to reuse them they are already yielded. I measured to be sure.

 

yeah... tty bolts twice is not a good idea. That lower portion of the cylinder bore definitely touches the skirt of the piston. The edges of the skirts go down below the bottom edge of the cylinder bore.

So frustrating to save and save and save for 10 months to get everything I need to drop this motor in to have to take it apart and mess with the bottom end. Now I have to get a 1/2 torque wrench ( sold my snap on one to a friend ), headgaskets and headbolts. No point not to replace the main / rod bearings when its apart too. May as well replace the lifters and lifter trays too....