Rear exhaust manifold

[jon L]

Has anyone had any experience removing the rear exhaust manifold? 

Could you please send instructions.

[Padgett]

Not for a while, afair attach the manifolds while the engine is on a stand & disconnect at the collector for removal.

[DAVES89]

2seater is probably the  only guy that removed manifolds while the engine is in the car. But I think he is deer hunting. When I did the engine swap we disconnected at the connector and did the manifold removal with the engine out.

[2seater]

Fairly straightforward but it is a tight fit to remove.

 

The rear manifold to tailpipe connection must be removed from below the car. I use a long extension and a universal joint to get the socket on the nuts. Normally it is rusty enough that the entire stud, nut and spring unscrews all together, which is just fine.

The EGR connection on the rear manifold must be disconnected at the manifold. Since the engine in question has been supercharged, which may not have egr, so much the better. If it has egr but is the newer system for the S/C engine, it connects to the front manifold and isn't an issue.

The manifold to head itself is six studs, 14mm socket IIRC. If it still has the engine lifting plate in place that needs to be removed first. 13mm nuts. With the S/C configuration the power steering reservoir may need to be moved aside and I have found removing the heater blower motor may be required to snake the manifold out and up. 

I do not remember if the transmission dipstick tube support bracket bolts to a manifold stud or not. It it does, just loosen the attachment and rotate the tube out of the way. Do not pull the tube out of the trans or a big oil leak will occur.  

[jon L]

Thank you, 2seater, I was unsure if it could be done. My power steering unit is mounted to the front pulley bracket. Do I Still need to move it?  I was unsure if the heater blower was in the way. Thanks for information. It appears that the trans dip-stick ias attached to the block or the head and not to the manifold. I am in the process of attempting the removal of the manifold at this time. After starting the job, it appears that it cannot be done. But now that you have assured me that it has been done, I will continue.  Thanks again.  I may be asking for more help in the near future.

[Ronnie]

I've not done what you are wanting to do. I think it might give you a little more room in the rear if you disconnect the dogbone up front and use a strap of some sort to pull the engine forward as much as you can. I've used one of my tie-down straps made for holding things on down my utility trailer before to keep the engine pulled forward to change the rear spark plugs and it works pretty well. Your SC engine might be different and this won't work...

[2seater]

I did forget to mention the crossover connection from the front manifold needs to be disconnected, which can be done with a long extension that passes under the throttle body🤢 Pull the spark plugs too, otherwise the mounting flange will likely damage them or hook on them. I am only somewhat familiar with the location of items on the S/C engine but I thought the power steering reservoir is high on the drivers side rear, but maybe not. 

[jon L]

Yes, The power steering reservoir is mounted on the throttle cable bracket, but I removed it and moved it away.

Great idea, Ronnie. I wasn't sure the engine would move forward. I will try that. I now need to locate the bold that holds the transmission dipstick bracket and remove it.  How hard is it to remove and reinstall the dipstick tube? ( I plan on draining the transmission, it has a drain plug).

[2seater]

I think you are correct that trans. dipstick tube bracket is on a stud that is screwed into the drivers end of the rear head. IIRC, it is a stud much like the exhaust flanges to the head. The stud has a hex shape for installing but also a threaded extension that has a smaller nut installed which is used to hold the clamp. It might be a fastener common to the heat shield over the exhaust under the throttle cables? Once that clamp is free, the tube will pull straight up and out. It has an o-ring seal into the trans. The fluid level in the trans is above the level of where the tube goes in so it will leak unless the fluid is first drained 

[jon L]

Now I feel confident that I will be able to finish this project. I am waiting for a tie down strap and The I will go back at it.

Here is the cause of all this trouble.   A new rear manifold with  2 1/2" down pipe. With this complete, I will be able to get

the air out. I had a restriction getting it out not in.

[Ronnie]

I don't know how well it will work when you get it on but it sure looks good!

[jon L]

Why do you think it won't work? It's been cut to 2 1/2" inside and appears to be wide open.

It's also been porter and polished inside.

Edited November 21, 2021 by jon L

[Ronnie]

 I wasn't intending to say it wouldn't work. I was saying I just don't know one way or the other and I was bragging on how good it looks. Maybe it sounded different from what I intended. That happens a lot when I'm typing on the computer. Sorry.

[jon L]

No, No, I didn't take it that way. I thought you had an idea that I missed. I thought I had everything covered and it seemed like maybe I missed something.

[2seater]

Is the connection in the original location and depth? It may be a trick of the light but it looks a bit longer where it extends toward the rear. It sure looks nice and I am a believer in ceramic coating exhaust parts.

[jon L]

It is about an inch longer and what you see on the end is the first part of the new exhaust pipe. the pipe will be extended.

It is also bigger around. That may be why it looks longer.

[jon L]

Buy the way, Ronnie, How much does the motor move when pulled back?

[Ronnie]

The motor won't move much Jon. After my last post I happen to think that my '88 has different motor and transmission mounts than later models so I don't know how much the motor will move on your car. Any amount you can pull it forward should help give you a little more room to get your hands back in there to work on the manifold.

 

It has been several years since I did it but what I remember is removing both bolts in the dogbone and taking it off. Then I put the bolt back in the dogbone bracket on the engine. I connected a hook on one end of the strap to the metal bracket the red arrow points to in the photo below, and connected the hook on the other end of the tie-down strap to the dogbone bolt - running the strap approximately across the area where the green arrow is pointing.

 

Next I inserted a huge screwdriver I have ( about 2 feet long) into the dogbone bracket on the engine and used it as a prybar to pull the engine forward while keeping the slack pulled out of the strap at the same time to hold the engine forward as much as possible. I don't remember exactly how I did that so you will have to experiment to see what works best for you in getting a prybar in place to pull the engine forward.

 

Once I got the engine forward as much as possible the hard job was putting my knees on the radiator support and hunching over the engine to get to the back plugs. With me having two bad discs in my back it is hell for me to stay in that position for very long. Putting an old quilt doubled up under your knees will help a lot but it is still an uncomfortable position to be in. Seems like having a supercharger on top of the engine would make it even harder to get to the back of the engine. Hope you can find an easier way to do it than I did. It might be a lot easier if you had the hood off so you have more room to move around. Maybe 2seater or Dave have some tricks they can offer to make getting to the back of the engine easier.

 

[2seater]

I'm a short guy so my issues may be different, but working on more than one item at a time, I found raising the rear of the car, like on stands or ramps, lowers the nose. This makes it easier to lean over the engine from the front and I place a cushion from something like an outdoor chaise lounge across the engine and front end to allow laying out on top of the engine, sort of like this. This is my grandson on the red crusher Reatta revival.

[Padgett]

That's the same way I do it, just lie down flat on my stomach. No knees atol.