360 vacuum help

[FOM05]

Need some with the vacuum system on my jeep. I have been going through the vacuum lines and replacing them one at a time trying to eliminate any leaks. The PO's have taken out the emissions system, the air pump and I am sure many other things I haven't realized yet. It does have a new Edelbrock Carb 1406 on it. I have a TSM for the 360 and for the carb. I have been looking them over, but there is so much missing I am not sure if it is hooked up right.

Here is my problem. On the front side of the carb there are three ports. The center one is the PCV port, no problem.

The one on the right a 3/16" manifold vacuum ( Distributor vacuum advance port for non-emissions controlled engines) This one is hooked directly to the vacuum advance.

The left side one is a 3/16" timed vacuum ( Distributor vacuum advance port for emissions controlled engines) This one is capped off.

I also have nothing hooked to the EGR valve or the EGR CTO switch.

Also the manifold vacuum? ( top front of engine near oil fill) has two ports on it and only one is connected to the brake booster and the other is open.

Ok, so finally the questions. Is the carb hooked up correctly to the ports? Should I reconnect the EGR valve? What does the other port on the manifold
vacuum go to.

Thanks for your help.

[Tripwire]

please edit your signature to include your year and any other modification info... it helps us answer your questions better

i have a schematic for an 86 if you need it

[Rich88]

Welcome to the obsession!

Signature editing to add your stuff is done by going to the "User CP" tab.

Vacuum diagrams (and other good stuff) are available from http://oljeep.com/gw/vac/GW_vacuum.html.

Getting the right year's diagram should be your guide to restoring vacuum line sanity.

EGR should be connected to ported vacuum (as opposed to manifold vacuum). Ported vacuum can be verified by connecting a hose to a vacuum port on the carb and seeing if there's NO vacuum at idle. Rather you should only get vacuum there when revving the engine. A manifold vacuum port will have strong vacuum on it at idle.

The 360 is designed to run best with EGR connected...at least with the stock cam. The idea of disconnecting it to improve performance is a myth that refuses to die. Here's a read on EGR: http://en.wikipedia.org/wiki/Exhaust_gas_recirculation.

Disclaimer: Some can run OK without EGR, but it requires some advance knowledge of performance tuning that some people here can guide you on if you ever get to that point. But for now, recommend you get it working the right way for stock.

[FOM05]

Sorry about that. I think my signature should show up now.

If not, I have a 1978 Cherokee "S" Levi with AMC 360.

[FOM05]

The new EGR CTO is ordered. I will put it in tomorrow and see what happens. I will clean up the EGR valve and put in new hoses.

What about the extra vacuum port on the manifold vacuum, should it be plugged or does it go somewhere else? See pic below. I think this is the last port that I am not sure what to do with.

Thanks for the help.

[rreed]

It should be capped off--that is a vacuum leak. I run my distrib vacuum advance off it but not running any emissions at all (no EGR, but all fully tuned to no emissions). On mine, I ran the brake booster off the matching rear manifold port behind the carb, and on-board vacuum gauge off the small side of it. That front one as mention runs my vacuum advance and I think the other large side capped off? PCV I think is running off a port on the front or rear of my 1405.

A CTO will help activate the EGR valve after the engine is good and warm, and it should be attached to the ported port on the LH/driver's side of the carb that is currently capped off. If you're still running a charcoal canister that would also connect to the same ported vacuum (purge signal). Basically these two things should not be activated until the engine is good and warm and you're off idle.

Edelbarf has some great videos on their web site about tuning their carbs, I need to go back and refresh on them. It's an exceedingly simple carb to tune and rebuild. And welcome aboard!!

[Rich88]

The new EGR CTO is ordered. I will put it in tomorrow and see what happens. I will clean up the EGR valve and put in new hoses.

What about the extra vacuum port on the manifold vacuum, should it be plugged or does it go somewhere else? See pic below. I think this is the last port that I am not sure what to do with.

Thanks for the help.

If you're not running distributor vacuum through a CTO per the stock diagram, then that's a handy place to go direct to the dizzy vacuum advance diaphragm. (I do). To clarify, many choose to bypass the stock HDC and Spark CTOs and non-linear valve, and route vacuum to the dizzy directly from the manifold vacuum. Impact is negligible and simplifies things.

Otherwise when all is said and done and you have any vacuum ports unused, they need to be capped off.

[rreed]

Like Rich88 said, I connect my distrib vacuum advance to that open port on the intake, and capped off the ports on my Edelflood carb. And +1 on capping off any/all unused ports.

[FOM05]

Thanks for your help guys. I got everything hooked up and hopefully all vacuum leaks plugged on Saturday. Took her (Kari ann) out for a ride and she did great. Went about a 100 miles and the gas gauge didn't go below half.

Now on to the next projects. Fix the tailgate, build new bumpers, tire holder and replace the seats. That should keep me busy for a while.