Vacuum Line Help..With Pictures

[CJKrawler]

Need some help with a 360. I just got this thing, and I am trying to get it running. I was able to get it to start today, once a good battery was put in. Ater getting it running, I found a fuel line leaking . Ran to the parts store, got a new fuel and air filter, and some rubber fuel lines. Truck started, and ran a little better, but not much. I then discovered fuel leaking from around the carb, still not good. I am assuming the issue is from the gasket, so I pulled carb off, the gasket looks decent, but I need to replace it now anyways. While pulling the carb off, I am discovering some missing/disconnected vacuum lines that may be causing this thing to not stay running. Here is what I know for sure.

Electric fuel pump was installed at some point for t/s purposes
A holley carb replaced the original 2 barrell carb, i do not know the model of it.
There are two ports for lines on the air cleaner housing, but only one was connected to anything.
The line in the first picture was not connected to anything, nor was it blocked off. I have no idea what the piece that it goes to is for.

Any help, thoughts, or anything else would be appreciated. And if there are diagrams for the vacuum system, that would be great too.

Oh, and in the 3rd picture, lines marked 1 and 2 were connected to the air clear (1), and the back of the carb(2)

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[BusaDave9]

Here's some vacuum diagrams. They are for a CJ with a AMC 304 but it's the same engine as a 360 except the 360 has a wider bore. What did the 360 come out of? Did it ever run good in the CJ?

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[CJKrawler]

Thanks Busa, the 360 is still in a 77 J20 that I just picked up.

 

[BusaDave9]

I installed a fuel pump that put out 7 psi. If your pump puts out much more than that it could overpower your float valves and flood the engine. The extra gas should go down the throat of the carb and not outside the carb. If your pump puts out too much pressure you may need a fuel regulator.
Holley 12-704 - Holley Fuel Pressure Regulators - Overview - SummitRacing.com

 

[BusaDave9]

A '77 J20 with a 360
There are a lot of vacuum diagrams with slight variation. Here are a couple more to mull over.

 

[BusaDave9]

There are two ports for lines on the air cleaner housing, but only one was connected to anything.

Where does the one line on the air cleaner go? I only have one and it goes to the oil cap.

you have a 2 barrel manifold. Do you have a 2 barrel Holley or a 4 barrel Holley and an adapter?

 

[CJKrawler]

I have made a few notes on the picture you posted. The one line fromt he air clearner goes to #1 in the picture. I will look the other diagrams over to see what I can see. I am still trying to figure out the mystery line that runs down near the distributor. It has not had anything attached to it in a while. To top things off, the truck has not ran reliably for the PO is several years, and they quit trying about a year ago.

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[CJKrawler]

[/QUOTE]
you have a 2 barrel manifold. Do you have a 2 barrel Holley or a 4 barrel Holley and an adapter?[/QUOTE]

It looks to be a two barrel adapter.

I just saw your reply in the other thread about vapor lock, and the fuel pressure. I have been wondering about that myself. I need to get under there tomorrow and have a look at the block to see about the mechanical pump. The PO put a Napa fuel pump on that may be putting too much to it, I also need to find out which Holley I have so that I can determine how much pressure it should have going into it, if I keep the electric. Sound like I am thinking in the right direction?

 

[BusaDave9]

the mystery line that runs down near the distributor.

Their should be a line going to the vacuum advance on the distributor.
Do you have a hose that connects to your oil cap going to your air cleaner?

 

[CJKrawler]

Their should be a line going to the vacuum advance on the distributor.
Do you have a hose that connects to your oil cap going to your air cleaner?

I will go back and look at the distributor again, but I don't recall seeing one. Yes, I do have a line from the oil cap to the air cleaner. Will edit once I look at the dist.

Ok, I did find the line going to the distibutor, and it is already connected.

 

[CJKrawler]

A little update on this, I remembered that I kept the carb from an old AMC 304 that I once had, another Holley. I cleaned it up, and put it on this morning, no more fuel leaking. I still am not sure where the mystery line is going to, and now I am not getting the engine to fire, at all.

Should I switch back to a manual pump? I put a pressure regulator on this morning also, which is adjustable. I have it turned down pretty low, so I don't know if the engine is not starving for fuel, so it won't crank maybe?

Thoughts?

 

[BusaDave9]

You already have the electric pump and regulator installed. I'd keep them on. If you starve the engine of fuel it will happen when you are on the highway trying to accelerate uphill. It will still start and run under low load circumstances. If that happens turn up the fuel pressure.

How is the jeep now? Still not starting?
You can disconnect the fuel line from the carb and turn the key on. This will check to see if fuel is being pumped.

 

[CJKrawler]

Thanks for the info Busa, It is not starting anymore. The other carb did fix the fuel leaking issue. The other carb also worked very well on the old AMC 304 . I will check the fuel flow tomorrow night once the baby goes to bed.

 

[CJKrawler]

Just an update, it was fuel delivery. There was a major clog at the pump. Engine now runs, a little rough, but I havent done the plugs yet. Next job, drop the fuel tank.