Need some advice: CIS Removal

[KMoore68]

Hi,

In preparation for installing some ITBs this winter, I am removing the CIS on my 1977 911 S Targa with a 2.7.

I have runners 1, 2 and 3 removed, and the throttle linkage disconnected. I have the bolts on runners 4, 5 and one of the bolts on runner 6 removed however I can't access the last bolt on runner 6.

I have removed the AAR however on runner 6 there is something bolted to the back of it, possibly the cold-start valve, i'm not sure. It looks like I need to remove the bolts that are attached to runner 6 for this value before I can access the intake stud. Does that sound correct?

I'm been doing this so far in-situ however I've read that a partial engine drop will make access to this last runner easier, is that correct?

Any thoughts?

[boyt911sc]

You have the correct approach for CIS removal. You could make it more convenient if you have a 1/4” flexible 13-mm socket to access the inner #6 cylinder intake bolt and do an optional partial drop. The key to success to this type of work is mental attitude. It requires patience and perseverance.

Tony

[rwest]

The number 6 intake nuts are a major pain to access. I don’t think a partial drop really helps as the obstruction is the runner itself, not the car.

I bought a whole bunch of different swivel and extensions to try and remove it. If memory serves, I had the best luck with a Snap-on wrench that has a swivel socket on one end and an open end wrench on the other.

[rwest]

Also, be super careful not to drop anything in your open cylinders. I always keep track of every bolt and washer I remove; a magnet on a stick tool is helpful.

After you get the runners off and have every fastener accounted for, tape off or put a towel in the intake holes.

[montauk]

Originally Posted by rwest

Also, be super careful not to drop anything in your open cylinders. I always keep track of every bolt and washer I remove; a magnet on a stick tool is helpful.

After you get the runners off and have every fastener accounted for, tape off or put a towel in the intake holes.

Sage advice. Unfortunately for me, I let a washer slip into #5. And of course, the valve was open enough for it to drop into the cylinder. I could see it with my borescope but I couldn't get a pick on it to grab it.

I put a nozzle on my shop vac that fit the intake tightly and pulled out the spark plug. It instantly sucked the washer out. I should mention that I cleaned out the shop vac so that I could be sure the washer was indeed captured. What a relief. I thought I'd be taking the engine apart to get to it.

[joe912/62]

I did this last year and what I did was to remove the #4 and 5 runners. You will have to undo the short rubber hoses to be able to twist them off. Start with #4 and then 5 until you get to that nut. Worked for me without dropping the engine..

[chrismorse]

Originally Posted by boyt911sc

You have the correct approach for CIS removal. You could make it more convenient if have a 1/4” flexible 13-mm socket to access the inner #6 cylinder intake bolt and do an optional partial drop. The key to success to this type of work is mental attitude. It requires patience and perseverance.

Tony

Someone once opined that strength doesn't get the job done, nor intelligence, or skill, or knowledge, It requires consistent effort-Perserverance gets it done.
And, the sharing of experience and knowledge on this forum sure is a big help.
Dazed and confused,
chris

[PeteKz]

In addition to the others' comments: I use a 1/4" drive 6" long wobble extension on a 1/4" drive socket to get at several of the nuts. Go slowly and carefully. I can remove the whole CIS assembly off the top of my 3.0/3.2 engine (in a 1973 car)without partially dropping the engine. It takes me about an hour, but I've done it several times, so I have the practice. I also don't have the cold start valve and AAR installed, which makes access easier.

[KMoore68]

Originally Posted by rwest

Also, be super careful not to drop anything in your open cylinders. I always keep track of every bolt and washer I remove; a magnet on a stick tool is helpful.

After you get the runners off and have every fastener accounted for, tape off or put a towel in the intake holes.

Thanks, i've been closely accounting for every nut and washer as I pull things apart.

This week, i'll work on removing runners 4 and 5 and do a partial drop to remove the cold-start value and then hopefully runner 6

[mike sampsel]

Originally Posted by KMoore68

Hi,

In preparation for installing some ITBs this winter, I am removing the CIS on my 1977 911 S Targa with a 2.7.

I have runners 1, 2 and 3 removed, and the throttle linkage disconnected. I have the bolts on runners 4, 5 and one of the bolts on runner 6 removed however I can't access the last bolt on runner 6.

I have removed the AAR however on runner 6 there is something bolted to the back of it, possibly the cold-start valve, i'm not sure. It looks like I need to remove the bolts that are attached to runner 6 for this value before I can access the intake stud. Does that sound correct?

I'm been doing this so far in-situ however I've read that a partial engine drop will make access to this last runner easier, is that correct?

Any thoughts?

It is the air box mount bolted to runner number 6 on my 78, you can likely reach it but you might not need to if you lift off the air box with the runner (Cold start electrical and the other plug need to come off to pull up the air box, it has another mount on the throttle linkage mount) 12 mm swivel and 1/4" socket set, some stubby wrenches. I takes some time to get it off (the #6 nut). I think it's 12 mm nut on mine, anyway the size of the nuts is the same on all the runners.

Partial drop not needed but might help depending on the tools you have and use to get and move the ratchet for number 6.

[KMoore68]

Success! I had to cut the rubber boot on the #4 runner, once I did that I was able to use my 1/4" socket to unscrew the previously unaccessible bolt, then the rest of the assembly lifted right off.

I was very careful to insert paper towels into the intakes so nothing will drop. I didn't rush myself and heard alot of good advice on being patient and researching, thanks to all!

Next is figuring out how to disconnect the throttle? I have disconnected the springs but there seems to be a wire connected to the firewall that doesn't seem to have an area to detach.

[KMoore68]

Here is a picture of the problem area

[rwest]

If I’m looking at the right part, that is the cruise control cable and it appears that a previous owner used some bailing or safety wire to make sure it didn’t come out of the upper bracket.

If you cut that wire on the upper bracket that is sort of an “H” shape, you should be able to remove the cable.

[Pats79SC]

This is funny, I have my cruise control cable wired up in the same way from previous owner.
Pat

[montauk]

Originally Posted by KMoore68

Thanks, i've been closely accounting for every nut and washer as I pull things apart.

This week, i'll work on removing runners 4 and 5 and do a partial drop to remove the cold-start value and then hopefully runner 6

Are you adding a trigger wheel? I just did a partial drop and was able to get the crank pulley off. I've decided to add a cam sensor now so I'll be dropping the engine anyway.

[KMoore68]

Originally Posted by rwest

If I’m looking at the right part, that is the cruise control cable and it appears that a previous owner used some bailing or safety wire to make sure it didn’t come out of the upper bracket.

If you cut that wire on the upper bracket that is sort of an “H” shape, you should be able to remove the cable.

Thanks Rutager, it hadn't occurred to me that could be the Cruise Control from the previous owner. I'll cut it and continue with my efforts!

[KMoore68]

Originally Posted by montauk

Are you adding a trigger wheel? I just did a partial drop and was able to get the crank pulley off. I've decided to add a cam sensor now so I'll be dropping the engine anyway.

Thanks but no immediate plans to add a trigger wheel. For now I'm planning on just fuel via the ITBs, after that is sorted and running, I may move to a 123 Distributor or CoP and then look to adjust my fueling from batch to sequential and use a cam sensor.

I'm planning on walking before I run