Thanks in advance. I have dug around the forum in search for the answer but no luck, I know it's annoying to answer the same question over and over.
I have a 85 CJ7 with the standard 6. I installed the Webber kit along with Holley FPR as recommended. During the install, I noticed a vacuum port along what I believe is the brake assist line on the drivers side. This port is below the carb and points back to the firewall. I also found a loose green tube lying toward the bottom of the engine compartment but it is too short to connect. The end looks clean cut and unbroken. I do not know if it is related to my issue and if it should be hooked to this port
. After carb install, jeep idled very rough. In also noticed a loud sucking noise from this port. I covered it with my finger and the engine smoothed out. I assumed problem solved and put a cap over it. Test drive showed a lack in power. It would drive smooth just felt week and underpowered during acceleration I don't know if the unknown port and lack of power are related nor not. I have attached pics of the port the best I could. It is at the end of the pen. The only vacuum lines I have are from the carb to pcv, and carb across the engine to distributer.
The lack of original vacuum lines tells me the previous owner tweeked the original set up which is fine with me. No emission test to worry about.
That vacuum port is full manifold vacuum which explains the rough running with it open. That small port is supposed to be connected to the TAC system to give it a source of vacuum. I'm going to assume that the jeep has been pretty much stripped of emissions related components since you're using an open element filter. Just cap it off and know that it can used as a ready source for manifold vacuum for a gauge or perhaps vac advance.
When you capped that port off, did you by chance make any adjustments to the carb in an attempt to tune it or is the carb factory set? If you never changed anything after finding that vacuum leak, the poor performance may just be improper settings.
Thanks for all responses. I'm not very knowledgeable about the Jeep engines but given the research I've done, there is significantly less emissions tubing than factory. I will this port off.
The only adjustment I have made to the new carb is the idle speed. It was about 500 so I bumped it up to about 600. No other adjustments made by me.
HI, Ok the one you are showing should go to the brake booster . the only other one's that are necessary is the distributor vacuum, PCV and of course fuel line.. all others are emissions. lack of power could be distributor vacuum or timing.
good luck
tim
Find a timing light and ck the timing.
Set your idle to about 650-675rpm because when you turn on your lights and such. The idle will drop some.
This will give you a good idea of what Matt was say'n about all the vacuum stuff that was OEM. http://home.sprynet.com/~dale02/list.htm
From your pics it looks like I'm running the same carb. On mine the fitting you're pointing to is connected to the distributor for advance. That same fitting is part of a larger fitting that has the metal tubing coming from it (as shown in your pics). The metal tubing then connects to a flexible (rubber in my case) line that connects to the brake booster. Besides the gas connection, i've got connections for the PCV (on the top spacer plate just below the carb. You have a connection here, but i can't tell where it goes), and the bowl vent which connects to my vacuum canister (looks to be blocked off on yours?)
Also, i'm not running a FPR, just the OEM type fuel filter that has 2 outlets.
I will check the timing, seems to be the next logical step in this process. Thanks.
The vacuum line on my carb to dist is hooked up on the opposite side of the carb, closest to the valve cover. The PCV valve line is hooked to the plate that came with the Webber kit, just below the body of the carb.
That vacuum routing you're describing sounds fine. You have the vac advance at the distributor connected to ported vacuum and the PCV line is connected to manifold vacuum.
Since you did no adjusting to the carb/timing after you installed it, your lack of power is almost definitely due to that. First get the base timing set properly and then look up tuning guides for your Weber carb. You're going to more than likely change some things.
I started working on the timing and noticed a high pitch squealing noise from around the carb (new problem). I just installed the carb yesterday.
I was able to pinpoint the sound to the base where the conversion kit and manifold met by rubbing my finger to change the sound in that area. I removed the carb and noticed the very bottom plate on the conversion kit was cracked in several places.
Anyone know of a better quality spacer for the Webber?
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