L81 timing cover
Thread Starter
Safety Car
Joined: May 2001
Posts: 3,758
Likes: 3
From: Surrey
L81 timing cover
Hi, (I'm having an active week for posts :) )
Everything I've read, or heard, about timing cover removal states that the oil pan must be dropped slightly to get the timing cover off. Well, I removed all the timing cover bolts to size them up, so that I could make a few stainless ones, & the timing cover just sort of, er, well, it fell off in my hand! Honest! I didn't "wiggle" it or twist it about, it just fell off :confused:
I've noticed that a lot of aftermarket oil pans are for all models up to '81, so is there something different with the L81 timing cover seals? The big question is: as it came off so easily, I was planning on fitting it back on without dropping the sump. Is there any reason why I shouldn't do this? I'll be using a new gasket & seals with RTV & it didn't leak oil prior to "falling off".
:cheers:
Everything I've read, or heard, about timing cover removal states that the oil pan must be dropped slightly to get the timing cover off. Well, I removed all the timing cover bolts to size them up, so that I could make a few stainless ones, & the timing cover just sort of, er, well, it fell off in my hand! Honest! I didn't "wiggle" it or twist it about, it just fell off :confused:
I've noticed that a lot of aftermarket oil pans are for all models up to '81, so is there something different with the L81 timing cover seals? The big question is: as it came off so easily, I was planning on fitting it back on without dropping the sump. Is there any reason why I shouldn't do this? I'll be using a new gasket & seals with RTV & it didn't leak oil prior to "falling off".
:cheers:
Burning Brakes
Joined: Dec 2000
Posts: 1,183
Likes: 2
From: Des Moines Iowa
Re: L81 timing cover (UKPaul)
Paul, did you already have the pulleys and harmonic balancer removed? I guess you must have, if it 'fell' into your hand........Boy, my cover was pretty tuff to get off when I did a camshaft replacement last fall, and I had the front pan bolts out and loosened some.
Don't really know about the pan being unique for an L-81.
If you've gone this far, probably a good idea to check timing chain and replace if it shows any signs of being loose/worn.
Don't really know about the pan being unique for an L-81.
If you've gone this far, probably a good idea to check timing chain and replace if it shows any signs of being loose/worn.
Melting Slicks
Joined: Jan 2000
Posts: 2,386
Likes: 3
From: far, far away
Re: L81 timing cover (UKPaul)
Hey Paul! :D
I'm no expert (insert standard disclaimer here)... but...
I'm pretty sure the L81 timing cover and oil pan gaskets are the same as all first-generation Chevy small-block V8's. It's been awhile since I looked at mine, but as I recall, the lower half-circle of the timing cover gasket is captured by the oil pan. However, a "short cut" (that's one step short of a "Bubba" procedure) when replacing the timing cover gasket is to cut the old one off at the oil pan, leaving the pan undisturbed. Then, an identical piece is cut out of the new gasket, and the timing cover is installed with gobs of black RTV where the cut gasket surfaces mate up, as well as a film of RTV where the cover seals against the old gasket.
If yours has been done that way sometime in its glorious past, that would explain how it could come off the way it did. Properly done, with everything cleaned up with solvent so the RTV can stick well, I'm sure it works just fine.
P.S.: Whatever do you mean by "so that I could make a few stainless ones"? I know you're talented, and you seem to have an endless supply of time to work on that Vette (I'm jealous!), but you're not really making bolts are you?!?!? Good God, man! If you can't find SS bolts (1/4"-20, I think?) over there, I'll get some and mail them to you! :D :D
P.P.S.: Somewhere along about '81, the dipstick was switched from the driver's side to the passenger side. That may be why you see the oilpan reference that you noticed.
[Modified by Gator81, 3:16 PM 3/14/2002]
I'm no expert (insert standard disclaimer here)... but...
I'm pretty sure the L81 timing cover and oil pan gaskets are the same as all first-generation Chevy small-block V8's. It's been awhile since I looked at mine, but as I recall, the lower half-circle of the timing cover gasket is captured by the oil pan. However, a "short cut" (that's one step short of a "Bubba" procedure) when replacing the timing cover gasket is to cut the old one off at the oil pan, leaving the pan undisturbed. Then, an identical piece is cut out of the new gasket, and the timing cover is installed with gobs of black RTV where the cut gasket surfaces mate up, as well as a film of RTV where the cover seals against the old gasket.
If yours has been done that way sometime in its glorious past, that would explain how it could come off the way it did. Properly done, with everything cleaned up with solvent so the RTV can stick well, I'm sure it works just fine.
P.S.: Whatever do you mean by "so that I could make a few stainless ones"? I know you're talented, and you seem to have an endless supply of time to work on that Vette (I'm jealous!), but you're not really making bolts are you?!?!? Good God, man! If you can't find SS bolts (1/4"-20, I think?) over there, I'll get some and mail them to you! :D :D
P.P.S.: Somewhere along about '81, the dipstick was switched from the driver's side to the passenger side. That may be why you see the oilpan reference that you noticed.
[Modified by Gator81, 3:16 PM 3/14/2002]
Thread Starter
Safety Car
Joined: May 2001
Posts: 3,758
Likes: 3
From: Surrey
Re: L81 timing cover (Gator81)
Hi,
John: Damper & pulleys were off. The original cover can be replaced without dropping the pan by fitting it bottom 1st with the top tilted forwards. It can then be tilted into place, but I couldn't do it with the new cover. It must be because the lower seal had compressed over time, just enough to be able to fit it. I'd bought a Cloyes true double roller chain prior to pulling it all apart. Once the cover fell off I saw that it already had a double roller chain! Thinking that I'd just wasted a bunch of money I pulled the chain & sprocket off while muttering & cussing to find that it was well baggy & had JAPAN stamped on each side link :U It's now binned :)
Gator: Hi! I'm drilling holes down the centre of each non load carrying bolt - to save sprung weight :lol: Actually, it's so that if I ever get a seized bolt, rounded off head, etc, I can just drill a small depth into the head to reveal a concentric hole running down the shank of the bolt (memories of trying to drill out the thermostat housing bolts in the pouring rain while the 240V electric drill was sparking away :( keeps my mind focused on the job). Then I can break an EZ-out off inside the hole to end up in a fix quicker than if I'd had to drill down a stainless bolt b4 being able to break the EZ-out ;) I'm also machining & mirror polishing the heads (my lunchbreaks just fly by). But I will mention your offer to my local hardware shop, as I've cleaned them out of 5/16"UNC x 3/4 set screws!
Email coming your way as soon as I get a moment (Ha! that's a laugh) detailing the saga of my "quick" winter jobs ("while-I'm-at-it-itus has hit hard, along with Murphy's Law, Sods Law & general "That's just typical of my luck" stuff :) )
Take care m8
Paul
John: Damper & pulleys were off. The original cover can be replaced without dropping the pan by fitting it bottom 1st with the top tilted forwards. It can then be tilted into place, but I couldn't do it with the new cover. It must be because the lower seal had compressed over time, just enough to be able to fit it. I'd bought a Cloyes true double roller chain prior to pulling it all apart. Once the cover fell off I saw that it already had a double roller chain! Thinking that I'd just wasted a bunch of money I pulled the chain & sprocket off while muttering & cussing to find that it was well baggy & had JAPAN stamped on each side link :U It's now binned :)
Gator: Hi! I'm drilling holes down the centre of each non load carrying bolt - to save sprung weight :lol: Actually, it's so that if I ever get a seized bolt, rounded off head, etc, I can just drill a small depth into the head to reveal a concentric hole running down the shank of the bolt (memories of trying to drill out the thermostat housing bolts in the pouring rain while the 240V electric drill was sparking away :( keeps my mind focused on the job). Then I can break an EZ-out off inside the hole to end up in a fix quicker than if I'd had to drill down a stainless bolt b4 being able to break the EZ-out ;) I'm also machining & mirror polishing the heads (my lunchbreaks just fly by). But I will mention your offer to my local hardware shop, as I've cleaned them out of 5/16"UNC x 3/4 set screws!
Email coming your way as soon as I get a moment (Ha! that's a laugh) detailing the saga of my "quick" winter jobs ("while-I'm-at-it-itus has hit hard, along with Murphy's Law, Sods Law & general "That's just typical of my luck" stuff :) )
Take care m8
Paul
