I had an LT-1 rebuilt 6 months ago. It has been wrapped in dry storage since. I went out to start putting it together and discovered rust on the crankshaft where the rear main seal goes. Is there any preferred method for removing the rust, and is there any concern this will cause issues in the future?

Thanks for your input!

 

its outside of the internals, soak it with PB Blaster over nite next day use a scotch pad or emery cloth to clean it up, keep the rest of the engine covered and clean, when done use some lite oil on the rest of the engine to protect it, the plastic will draw moisture in cold damp wheather if its sealed tight and can't breath, I don't think you will have a problem later.

 

IFF it's light surface rust, buff it gently with 0000 steel wool. If there's no pitting, it should be fine. Either remove the crank or CAREFULLY mask off the entire crankcase area before starting and then thoroughly clean it afterwards. The resulting metal particles will destroy your engine if they get inside.

 

Great. Thank you for the input! Hopefully I can get it cleaned up. Anyone in the Fort Worth/Granbury area want to help with an LT1 install??

 

Not good. Bare metal parts should have had Vasoline or cosmolene put on them to keep moisture away. But, #000 steel wool and penetrant oil will get rid of most of the corrosion. ScotchBrite or emory cloth should get the rest without scratching the suface of the crank journal.

If there are pits caused by the corrosion, they will have to be dealt with before assembling the seal, or it will wear out in no time. That surface must be smooth and polished to minimize seal wear.

 

Take that crank to your crank shop and have them polish those journals - corrosion is very abrasive to bearings, so you don't want to do a half-assed job of dealing with that rust. Most crank shops will do a nice polish job on the journals for under $50 - this won't change the size of the journals.

 

looks to be just the flywheel flange and a little on rear main cap where the oil pump bolts on to me, the photo seems to make the flywheel flange look huge, take another look you can see a dowel in the flange, and the back of the block with a freeze plug, the rear main seal goes inside the rear main cap which is bolted down so the OP must be talking about the rear pan seal, its a wierd distorted photo.

 

Yes....but it's still corroded.

 

Dang. If I hadn't paid good money to have the shop put the block together, I wouldn't hesitate to take the crank to the shop. Something about tearing it all down that doesn't sit well. And, yes, I realize it's better to tear it down now than after it screws up on the road.

I need a gear head buddy.

 

As we mentioned before, you can use penetrant, etc. to remove the corrosion, then use ScotchBrite and/or emory cloth to polish the surface. If there are no 'pits' left on the surface, it should be fine. If you can barely feel some sub-surface damage when you get done with your 'hand' polishing, you had better remove the crank and have the journal polished.

Bare steel and moisture are not a good combination; and steel parts should be protected before storing for any period of time.

 

That is where the rear main seal rides, better have it clean & polished. Rust usually = rough finish.

 

Wouldnt take it apart just yet call your machinist to see what he says.

 

my dumb question of the day is what journal are we talking about ?

 

lol - I don't know what the things called where the rust is at. All of the crankshaft diagrams list the parts from the front.

 

the part in the distorted photo with all the rust on it is called the flywheel flange, its where the flywheel and clutch assy. bolts to, it lives outside the back of the BLOCK inside of the bellhousing, its aprox. 1/2 thick but the photo makes it look like the width of a journal, the only thing that rides on it is AIR, not the Rear Main Seal nor the Rear Pan Seal, IT IS NOT A JOURNAL, directly to the left of the rusty flywheel flange is a gap and then the Rear Main Cap where the oil pump bolts to and is bolted to the block, under it inside lives the Rear Main Journal, two piece bearing, and the two piece Rear Main Seal, the Rear Oil Pan seal lays on the rearward ledge of the Rear Main Cap, you don't have to pull the rotating assy to remove the rust on the FW flange or polish anything, temporarily place your oil pan on the engine and carfully clean the rust off of the flange, don't use steel wool it flakes and falls apart you don't need any of it getting inside.

 

It is a post '86 engine. Look at the stud facing to the rear, it is one of several that retains the rear main seal housing on the later engines, the pan seals on the seal retainer. The pan seals on the rear main cap on the earlier blocks.

 

That's correct. It's a 94 LT-1 out of a vette. I'll take the long journey to the machine shop tomorrow and see what they think about it. I like the idea of polishing it without removing anything!

I did soak it in PB Blaster overnight. Didn't seem to make any appreciable difference.

 

well I'll be damn'd, goes to show ya how many late apart LT-1's I've looked at, this thread been up for at least a week, why didn't one of you kind gentlemen tell me this before I went out and made a horse's a$$ of myself.....I told ya the photo looked wierd, Thanks for the correction.

 

You're probably ok, long as the journals aren't damaged. Honestly, you're wanting to lightly polish them anyway, before assembly. If not familiar with this, cut some wrapped 600 grit strips around the journals lubed with thinner. Wind a shoe lace around it a couple times, and work it a bit. Just about any engine blueprinting book, will show you this. If not already, SA Designs, Rick Voegelins blueprinting book's a good one to have. Lot's of good guidence in this one. Another tip. If storing stuff like this for awhile, wrap it in oil soaked shipping paper.

 

Clean it off using one of the manual methods suggested above... scotch brite stands less of a chance of getting stray fibers all over the engine... but I personally use steel whool and follow up with a compound. Mask off the crank to keep debris from getting into the engine. After the compound (Mothers mag polish works), using a bright (500 watt) light, I look to see if I can still see rust "stains". If yes, then I polish it using my crank polishing equipment (which I keep in storage, PITA to set up). In your case, if you still see stains then take it to a crank/machine shop. If I use a compound on it, I use a series of solvents & soaps to remove the compound from the pores of the crank. Been doing it this way for over 40 years and never had any issues with my technique, including the use of compound. Just be "****" about cleanliness. Based on my experience, having dealt with many rusted cranks, and based on your pic, I would bet that you will still see rust stains (and possibly mild pitting) after cleaning it. The stains are rust which will heat up and eat into your rear main seal. This is one of those things that only years of experience will rule. I.E.- making a bad judgement and having the seal leak. If it cleans up, then you're good to go. If not, then you need to get it taken care of. Use Q-Tips to clean out the flywheel/flexplate bolt holes before you finish assembly. I just finished doing another one of these.