CIS Installation - is the an "Order of Operations"

[Tidybuoy]

I recently had my CIS removed so that I could do some oil leak maintenance. I'm happy to say the car is all back together and running well (and not leaking).

However, during the re-installation process, I thought I was doing right by assembling the "spider" on the bench and making sure everything was tight. This only proved to be a waste of time since nothing would fit properly and I had to loosen everything up to get the intakes to move and fit.

I eventually discovered that I could remove the driver side intake runners, install the passenger side, then slide the rubber connectors all the way onto the runners, fit the air box and slide the rubber connectors into place and tighten. It's easy to tighten the driver side while in the car, the passenger side is more difficult.

So, my question is: how do the pros do this.

Lastly, I have a '74 so it's probably the easiest of all CIS without any components that the later cars have.

Any advice would be great.
__________________
Vern

[snbush67]

Lower the engine a couple of inches.

[thumbdoctor]

Originally Posted by snbush67

lower the engine a couple of inches.

+1

[snbush67]

Use floor jack raise to support the engine, Loosen the transmission mounting bolts and disconnect the coupler (this may or may not be necessary but just do it to avoid damage). Loosen the engine mounting bolts a bit, now lower the engine a little at a time., loosen the bolts, lower some more. You can actually lower it quite a bit, just go slow.

[Vereeken]

I know I am going to get shot, but it is even not necessary to lower the engine (but it does help).

I have done it last winter. Would I do it again? Yes but not in the winter

It is tuff on the back.

This is on a 911 SC Euro model so with hard fuel lines and some extra stuff (AAR, AAV, WUR, Decel)

I removed the popes hat (boot between throttle body and air intake), Wur and AAR.

However it you get a rusted bolt on the inside of 6 or 5 you are f@%ked.

But I see the temptation that arises when you have the engine out to rebuild and install the CIS out of the car....

Michel

[Tidybuoy]

The problem was not space ('74 CIS has lots of room in engine compartment). The problem was that I tightened everything up on the bench and then when I tried to install, some intakes were twisted just enough to not want to fit over the intake studs and needed to be loosened up so that I could twist into position - this defeated the "pre-tightening".

So, I was thinking that maybe CIS gets installed differently. Or, maybe with the engine out, it's easy to make quick adjustments to the tubes and still install as a complete unit. I thought that maybe there is a simple order of operations since you can tighten the hose clamps on the center tube easier if the outer tubes are not yet installed. Then the back tubes, and then the front....just an idea on my part.

Regardless, I got the whole unit installed and things are running fine.

[snbush67]

You did it the right way, the end justifes the means.

[Jim Williams]

Originally Posted by Tidybuoy

I recently had my CIS removed so that I could do some oil leak maintenance. I'm happy to say the car is all back together and running well (and not leaking).

However, during the re-installation process, I thought I was doing right by assembling the "spider" on the bench and making sure everything was tight. This only proved to be a waste of time since nothing would fit properly and I had to loosen everything up to get the intakes to move and fit.

I eventually discovered that I could remove the driver side intake runners, install the passenger side, then slide the rubber connectors all the way onto the runners, fit the air box and slide the rubber connectors into place and tighten. It's easy to tighten the driver side while in the car, the passenger side is more difficult.

So, my question is: how do the pros do this.

Lastly, I have a '74 so it's probably the easiest of all CIS without any components that the later cars have.

Any advice would be great.
__________________
Vern

You've apparent already done the re-installation, but here is what I've done in the past.

And after anyone reads this, but before you say it's not worth the effort, you won't know until you've tried it both ways...

For an entirely different reason, I built a fixture from a piece of plywood, with holes that matched the intake ports for attaching the runners. Granted, it does take a little time to carefully measure where the holes need to be positioned and drilled. Then, once bolts are installed from the bottom of the piece of plywood to match where the intake studs are on the heads, put the runners in place and reconfigure the CIS while it's out on the work bench and all the boot clamps are accessible.

Then remove it from the plywood fixture and drop it back in place on the engine. It will take only a little positioning of the runners to get the holes in the runners aligned with the intake studs.

A partial drop is still recommended.

[boyt911sc]

There are several ways to skin a cat. Someone's method might not be acceptable to others and thinks his method is better than the other. For me, it is a choice. Whichever you decide to use for your work depends on your needs, skill level, and objective (goal). My very first CIS unit removal was done in situ because I've never done an engine drop before and the anxiety of doing an engine drop by myself alone was overwhelming.

Years later, I did my first engine drop and R&R the CIS unit. It was very convenient to do all the work and thought this was the correct way to do it!!!!! After several successful engine drop projects, came a disappointment, the engine failed to start. It would stay running a second or two and stalled. The temporary setback directed me to find a way to solve this problem. So I asked myself, how could I assure myself that the next engine I'm going to install will run on the first or second turn of the ignition switch?

My answer was why not test run the engine before installing it back? So you are certain that you or the other guy will have no problem starting it. So the last 12 years, I rather drop the engine and do all the subsequent work sitting down and test run the engine/motor before installation. Building a test stand may not be for everyone but for someone who does a lot of engine work like myself, my objective and goal slightly differs. Just do what makes you feel comfortable and it is your choice. Next time you'll know which one to implement.

Tony

[nicfranc]

I just did this and found that a Partial drop was helpful.

Jack the car up so the bumper is waste high.
Tools: Swivel 1/4" and 3/8" 12mm and 13mm sockets with extensions.
Ratcheting articulating box ends are also useful.

I made up masonite block offs for the intake ports to prevent nuts and washers from falling in intake ports.

I installed all the gas lines and vacuum pipes to the rear of the box
while it was on the bench. Leave the rubber dome off till last.
Install the brace and rubber mount onto the right side of the air box.
Prop up air box so you can attach the engine breather hose. (Take your time here)

I installed the #6 runner and tightened the intake nuts.
I then placed the air box in and attached the #6 rubber manifold sleeve.
Reuse the original clamps as they work well.
Attach the right side brace to the back of the #6 runner.

I then installed the #3 runner.
I slid the rubber manifold sleeve back over the runner. I used vaseline to help to slide the sleeve back over the runner. Once the runner is in place you can pull or push the rubber sleeve onto the air box connection port and tighten clamps. Position clamps where you can tighten them with a long screw driver.

Now install the #5 runner tighten the clamps and then install the #1 manifold runner.
Same procedure of applying vaseline and pulling the rubber sleeve back over the runner.
reposition the rubber sleeve to go over the port on the air box tighten clamp. Then install #4 and then #1 using same procedure.