Tube fitting on side of Distributor

[Riverrat]

It's just sittin' there with no tube connected to it. That standard?

This truck, after engine rebuild, won't idle. might this be the cause or is it more likely carb related?

I recall hearing the carb is a little sensitive when it comes to idling. There is a passage across the top of the bowl that runs around to the side of the carb and then down to the idle adjustment screw. This passage is sealed by the carb top cover gasket. If there is ANY air leak
into the passage your truck will not idle. Or if there is dirt in the jet where the gas is drawn into the idle passage. You have
to pull out the hand throttle to get it to run slow. Also, the float must be properly set and working well.

Any thoughts?

Thanks,

Chuck

[rickv100]

Chuck,

Are you referring to the two tube fittings on either side of the distributor? If so they are vent lines that run to the air intake elbow.

Rick

[hbb]

Chuck:
To make the engine idle and run properly you should make sure that all possible vacuum leaks are attended to. Make sure the cooling lines are running to and from the distributor. The crank case ventilation line is connected to the air horn and oil fill tube and is functioning, basically put it together as it should be, follow the TM’s for routing and connection points, but if you have a vacuum leak it will most likely have a high rpm idle. But are you asking a question or telling us information? You are talking about a possible flooding condition! Have you inspected the carb for contamination, have you checked the needle and seat to make sure the needle is not sticking and flooding the carb, maybe check the fuel pressure at the carb and how about the fuel filter? Best to make a log of the repairs and readings you are getting so you have a fall back to now where you have been and what has been done.
Good luck
hb

[8543bob]

Good morning all,
I just had my whole engione apart, with the distributor on the bench, i did not see any cooling lines to the distributor. Are you referring to the two vent lines that run from the dist to the air intake just aft of the air cleaner?? I dont think Imissed anything.
Bob

[Riverrat]

Yes -- I'm referring to the two vent lines that run from the dist to the air intake just aft of the air cleaner.

Thanks for input, guys!!

[cuz]

The vent lines for the distributor serve two purposes.
1-they vent explosive and corrosive fumes from the distributor.
2-In really warm climates they help cool the distributor and it's coil.

[hbb]

That was my bad calling the lines cooling lines; they are vent lines that help keep the coil temps down. They run from the intake air horn down to both side of the distributor and circulate air around the coil.
hb

[Joe]

The vent lines for the distributor serve two purposes.
1-they vent explosive and corrosive fumes from the distributor.
2-In really warm climates they help cool the distributor and it's coil.

A little more than that, the arcing that goes on around the rotor and terminals as the rotor moves and the arcing as the points open and close causes the air in the distributor to ionize and become conductive and that would cause things to short out. Therefore distributors have to be vented to prevent the build up of ionization. Racers used to actually drill big holes in the side of the caps between the spark plug cable sockets to make sure the caps were well ventilated.

[ZGjethro]

I built a really nice air intake and put a K and N filter on it. I am going to thread the crankcase breather into it, and that is all. The brake vent was eliminated before I bought the truck and I am going to put a small filter on the gas vent tube. The venting of the distributor is going to be taken over by the vacuum pump on the fuel pump. I have changed over to a pertronix pointless ignition so ionized gases are not a problem, but the coil still needs to be cooled. If the vacuum pump sucks air through the distributor, can anyone see a problem with my plan? I posted this idea some months ago, but now I am about to implement it.

[hbb]

The only thing that I would include would be something that will filter the air being sucked through the distributor to prevent any blockage of the airflow!

hb

[ZGjethro]

Thanks for the input. I am going to get a couple of the Kand N crankcase breather filters for both the gas vent and the distributor vent lines. I have been running the truck for several months now with no cooling of the coil, but I do not want to have an early coil failure, so I need to get this venting done.

[cuz]

I recall your earlier post. The system you suggested was already used on the Willys M38 and M38A1 and will work just fine but I think I already mentioned then that you need to insert a 0.040 restriction in the tube between the vac pump and the distributor.

[ZGjethro]

Cuz, I remember you posting about the restriction before. What is the purpose of the .04" restriction? I am not going to use the wipers if that matters. They are going to get an electric retrofit if I can find a small and inexpensive option there. What would happen if I used no restriction?

[cuz]

The restriction wasn't for the wipers. If you allow that full flow of vacuum to the distributor vent system you will have trouble getting the engine to idle correctly.

[ZGjethro]

First off, Riverrat, sorry for the thread highjack. Since I have taken it this far I have a few more questions.

Cuz, I thought the distributor lines were for cooling only. Since there is no vac advance how would it affect idle? Would enough air be pumped into the intake manifold to affect the idle? What if I did not run the line from the fuel pump into the intake manifold and put a filter on it instead? The reason I do not want to put the lines back on the air intake is that mine are all messed up and I think there has to be a better system of coil cooling than the pressure difference in the air horn. That and I like the clean look of my engine without spaghetti lines running all over it. I even have a 12 volt aquarium bubbler to use, but I do not want to add any more electric items to the truck. The bubbler might move too much air through the distributor if that is possible.

The original system seemed well designed for a river fording vehicle, but mine will never do that now. I do not need to have all my vents routed into the air intake, and I am not interested in an original restoration. My truck is a summer driving vehicle with almost everything original. I have not done any permanent alterations. I just do not want to do anything which will lead to reliability issues.