Removing Plenum
Thread Starter
Pro
Joined: Apr 2001
Posts: 744
Likes: 13
From: Lenoir City TN
Removing Plenum
Can it be done without removing the runners on an L-98? I've had the top apart before to fix the dreaded oil leak on the intake, so I had to remove the runners anyway. But if I remember the Plenum is angled on both sides and maybe will pull straight up. Anyone ever do this? :confused:
Melting Slicks
Joined: Apr 2002
Posts: 2,631
Likes: 2
From: Clever, MO aka SOMO
Re: Removing Plenum (cshuman)
Yes, the plenum can be removed by itself without messing with the runners. Be sure to get new plenum gaskets before reinstalling. It comes off pretty easy. You can leave the throttle body on also. I did this project once to replace the egr valve on my '88. Take your time and do it right the first time.....that's my motto! Took my about an hour to r/r the egr.
Good luck,
Good luck,
Heel & Toe
Joined: Jul 2000
Posts: 22
Likes: 0
Re: Removing Plenum (cshuman)
Just removed the whole top of the engine on my '85 L89 yesterday. The FSM says to loosen the passenger side runner before removing the plenum, and I could see no other way to do it. I couldn't get at the electrical connection under it otherwise. I am a novice with c4's so maybe there is a way. Good Luck
Thread Starter
Pro
Joined: Apr 2001
Posts: 744
Likes: 13
From: Lenoir City TN
Re: Removing Plenum (64FITanker)
I think Fixvet is right. Once you get it loose and lift it up a little you can hopefully get to the electrical connections. I am going to try it that way first anyway. Thanks for the input guys! :yesnod:
Thread Starter
Pro
Joined: Apr 2001
Posts: 744
Likes: 13
From: Lenoir City TN
Re: (scorp508)
The sides of the plenum are angled a little. I think it is enough to let you set it back down onto the runners when its put back together. I thought it might work, Fixvet says he has performed this magic before
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Removing Plenum (cshuman)
Even with the TB attached you can raise the plenum without removing the runners. You may need to "nudge" it a bit at first though to get it started.
In fact, since two lower runner bolts are inside the lower runner bolts have to be tight before the plenum goes back in.
In fact, since two lower runner bolts are inside the lower runner bolts have to be tight before the plenum goes back in.
Drifting
Joined: May 2002
Posts: 1,581
Likes: 2
From: The Motor City
Re: Removing Plenum (65Z01)
Fixvet is absolutely right - you can remove the plenum without disturbing the runners at all. I just removed it on my '89 a couple of days ago and was suprised how easy it came off. And the gaskets will go back easy too - the plenum-to-runner mating surface is angled and the gaskets themselves have little plastic tabs that hold them in place. Not a difficult job really.
Just make sure you have a #40 TORX bit ready before you start.
Good luck
Just make sure you have a #40 TORX bit ready before you start.
Good luck
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From: Airport Cruise-in 1 Veteran Airport Cruise-in 2 Veteran
Cruise-In II Veteran
Re: Removing Plenum (TheCorvetteKid)
I wish I was as lucky! When I removed the Plenum last year the runner to plenum gasket on the passenger side got severely wrinkled.
[Modified by War Machine, 8:34 AM 7/23/2002]
[Modified by War Machine, 8:34 AM 7/23/2002]