Plenum removal help
Thread Starter
Heel & Toe
Joined: Mar 2008
Posts: 21
Likes: 0
From: Wichita Kansas
Plenum removal help
I'm replacing the injectors on my '90. I've got the injectors and have d/l instructions so that I can hopefully do the job right the first time. However, I've run into a problem (of course). I have one last bolt to remove (torx) before I pull the plenum off. The head was stripped. I've tried cutting a slot in the head for a screwdriver, didn't work - too tight. Tried using WD-40, no help. Drilled center (off the mark) and used extracing bit - almost worked. Head broke off. Now I'm left with approx 1/4 of thread around the hole. Thought of drilling but that is just cutting into the alum (port tubes to intake) so I stopped. Can I run a blade between the plenum and the port tubes (for lack of knowledge) to cut the bolt so I can lift the plenum off? I'd appreciate any thoughts and recommendations.
Thanks
Russ
Thanks
Russ
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
If that was the last bolt and the head broke off of the thing should come off. The gasket may create a tight bond but if the bolts are out except for the broken off then pull that thing off of there...then use a stud extracter to remove the remaining threaded portion of the bolt that is sticking up.
Good Luck!
Good Luck!
Burning Brakes
Joined: Feb 2008
Posts: 988
Likes: 7
From: Sarasota Fl
I'm replacing the injectors on my '90. I've got the injectors and have d/l instructions so that I can hopefully do the job right the first time. However, I've run into a problem (of course). I have one last bolt to remove (torx) before I pull the plenum off. The head was stripped. I've tried cutting a slot in the head for a screwdriver, didn't work - too tight. Tried using WD-40, no help. Drilled center (off the mark) and used extracing bit - almost worked. Head broke off. Now I'm left with approx 1/4 of thread around the hole. Thought of drilling but that is just cutting into the alum (port tubes to intake) so I stopped. Can I run a blade between the plenum and the port tubes (for lack of knowledge) to cut the bolt so I can lift the plenum off? I'd appreciate any thoughts and recommendations.
Thanks
Russ
Thanks
Russ
However, the bolt sizes do differ and you will need a specific length bolt to replace it. When you put the bolts back on, make sure to run them through a die so they go in much easier and do not mess up the bolt holes. If you need a specific measurement, shot me a PM as I have the bolts mapped out still with the plenum off. Just be sure to specify which bolt it is, like 'passenger upper middle bolt', etc.
And don't forget to update us after the injector install.
If any of my information is incorrect, someone please inform me.....
Jonathan
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
I'm replacing the injectors on my '90. I've got the injectors and have d/l instructions so that I can hopefully do the job right the first time. However, I've run into a problem (of course). I have one last bolt to remove (torx) before I pull the plenum off. The head was stripped. I've tried cutting a slot in the head for a screwdriver, didn't work - too tight. Tried using WD-40, no help. Drilled center (off the mark) and used extracing bit - almost worked. Head broke off. Now I'm left with approx 1/4 of thread around the hole. Thought of drilling but that is just cutting into the alum (port tubes to intake) so I stopped. Can I run a blade between the plenum and the port tubes (for lack of knowledge) to cut the bolt so I can lift the plenum off? I'd appreciate any thoughts and recommendations.
Thanks
Russ
Thanks
Russ
Thread Starter
Heel & Toe
Joined: Mar 2008
Posts: 21
Likes: 0
From: Wichita Kansas
thanks for your responses. The bolt I'm having a problem with is the bottom on the passenger side. Think I will try to cut thru whats left of the bolt so I can pull the center piece up and out. I will keep you posted.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Because of the clamping effect alone I have never been able to remove the plenum without loosening the runner to base bolts.
In most cases, with long term gaskets it has taken a wack with a hammer to break plenum lose from gasket seal.
In most cases, with long term gaskets it has taken a wack with a hammer to break plenum lose from gasket seal.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
That hardened gasket has lost it's sealing ability, and likely is the source of vacuum leaks...
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Melting Slicks
Joined: Apr 2002
Posts: 2,118
Likes: 0
From: St. Charles, MO Route 66 Corvette Club
Russ:
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
Burning Brakes
Joined: Feb 2008
Posts: 988
Likes: 7
From: Sarasota Fl
Russ:
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
However, if you already did try the hacksaw method, you may want to go with a long file and knock down any high spots or imperfections you may have caused.
Jonathan
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Russ:
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
You asked for advice and here is what I recommend:
1. Remove the runner tube assy on the side with the damaged bolt. Once you remove the lower bolts (manifold), the runner should slide over the damaged bolt. The runner is a bitch to get off and the drivers side is the easy one to remove on my 89.
2. Use a pair of vice lock pliers and grab the OD of the stuck bolt and you should be able to remove the remaining stud.
3. Make sure you use anti-seize compound on the threads when you re-assemble the parts.
The use of a hacksaw blade between the runner and plenum can cause damage to the sealing surfaces of these two parts. I would spend the time to remove the runner and not take a chance on damaging critical part surfaces.
I have removed the plenum on my 89 many times and did not have to loosen the lower runner bolts.
Hope this is helpful to you!
Bob
hacksaw blade is a "shadetree" approach.
Thread Starter
Heel & Toe
Joined: Mar 2008
Posts: 21
Likes: 0
From: Wichita Kansas
Here's a little update. Finally some success. I have the plenum off now. I stumbled across a tool in my tool box that resembles a feeler gauge on steriods. It's about 10" long and 1 1/2 wide, with a rounded end and complete with a wood handle. It's sturdy but flexible (that makes a lot of sense). I used it on both sides of the gasket on both sides of the plemun. Once the gaskets were removed, I had plenty of space to run a saw blade down to the bolt I was having problems with. Little if any scaring to the plenum or runners from the blade. 98% of the metal fragments and shavings I picked up with a magnet. A little more clean up, removing the remaining bolt from the plenum then on to replacing the injectors. There's still hope for me yet!
There's still hope for me yet!
Thread Starter
Heel & Toe
Joined: Mar 2008
Posts: 21
Likes: 0
From: Wichita Kansas
Has this turned into a project or what. Here's the next question. Ive read there are 6 bolts on each side for the runners. 3 for each pair/set. On the passenger side, I can see the three on the back runner. Where is the third on the front runners. One over the intake toward the front. One bottom center on the outside. Where is the third bolt?
I can't believe how tight some of these bolts are.
I can't believe how tight some of these bolts are.
Thread Starter
Heel & Toe
Joined: Mar 2008
Posts: 21
Likes: 0
From: Wichita Kansas
getting there
Finally, I was able to pull the fuel rail off tonight. I had trouble with another bolt that was seized. On the fuel rail no less. I tried 4 different penetrating oils with no luck. Cut a slot in the head of the bolt and tried an impact screwdriver, no luck. I had to cut the bolt head off to pull the rail. I'll let the threads soak in oil tonight, then tomorrow I'll try my luck with removing what remains of the two bolts I had to cut. Cant hardly wait to get this car back on the road. At times, this has been frustrating. Since I like working on cars, it will be rewarding when the job is finished.
