Help with L98 plenum runners
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
Help with L98 plenum runners
Help! I'm in the middle of taking off the valve covers, plenum and runners (down tubes) to have them powder coated. Got the plenum off and the runners sticking up in the air. Got all five Hex bolts out of the bottom of the runners and the darn things won't move. I've pounded on them with rubber mallet and they seem stuck like they are glued on. Any help appreciated.
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
There are 2 bolts that go in the opposite direction inside the runners. The one for the passenger side is behind the egr switch on the front of the manifold and the one for the drivers side is back behind the egr valve in front of the distributor 
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
Wheelman,
Beautiful...found them and the back one came out without too much trouble, BUT how the heck can I get around that wiring harness contraption that's fitted on the maniflod right behind the TB? It's about 1 inch away from that front bolt and it doesn't seem to want to come out and stopping me from getting to that inside Hex bolt. Thanks.
Beautiful...found them and the back one came out without too much trouble, BUT how the heck can I get around that wiring harness contraption that's fitted on the maniflod right behind the TB? It's about 1 inch away from that front bolt and it doesn't seem to want to come out and stopping me from getting to that inside Hex bolt. Thanks.
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
There are two (10mm i think) nuts that hold that harness to the lower intake manifold between the runners. If you unplug the injectors and pull the wires out of the way you can get to the lower runner bolts easier.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
You will need to disconnect the cold start injector from the fuel rail to remove the left side runner. If it won't stop oozing fuel, disconnect the fuel lines at the right front of the fuel rail and loop a piece of rubber tubing between them, with hose clamps on it.
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
Wheelman = Thanks.
Trog = I saw that but I jury-rigged a small T-40 Torx head and very small open end wrench and was able to back out the bolt without undoing the thermostat bolt.
Plenum is off. Passenger side valve cover and runner is off.
Drivers side. 65Z01 = before I can even get to the runner, I take off the valve cover. Guess what...it's hitting on the bolt that goes through the air pump (I think) that's right above the alternator. Bolt head is 1/2 inch from pulley...looks like that all has to come apart to back the bolt out.
Trog = I saw that but I jury-rigged a small T-40 Torx head and very small open end wrench and was able to back out the bolt without undoing the thermostat bolt.
Plenum is off. Passenger side valve cover and runner is off.
Drivers side. 65Z01 = before I can even get to the runner, I take off the valve cover. Guess what...it's hitting on the bolt that goes through the air pump (I think) that's right above the alternator. Bolt head is 1/2 inch from pulley...looks like that all has to come apart to back the bolt out.
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Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
On my '88 I had to move the alt & AIR pump brackets forward about 1/4" to remove the left valve cover; the A/C compressor and AIR diverter brackets had to be moved forward and the EGR tube removed to remove the right side valve cover.
It realy isn't so bad, just a little tedious.
It realy isn't so bad, just a little tedious.
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,531
Likes: 35
From: Lecanto Florida
WOW...I did it! Only somebody up above knows if I'll ever get the thing back together again. I've got nuts and bolts and tubes all over the place marked with little notes and diagrams to tell me where most of them go back together. It hardly leaked any gas from the cold injector and I used a drummel to take the 1/4 inch of thread off the air pump bolt so the valve cover would come off.
Thanks for all the help guys. I might need some more to help put the thing back together when it comes back from the powder coating shop. They are doing the plenum, both runners and both valve covers with a bright silver plus clear coating it. I also have a small dent in one of the runners which they will fill in before coating it. $200.00
Thanks for all the help guys. I might need some more to help put the thing back together when it comes back from the powder coating shop. They are doing the plenum, both runners and both valve covers with a bright silver plus clear coating it. I also have a small dent in one of the runners which they will fill in before coating it. $200.00