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Old 02-12-2015, 03:08 PM   #1
Jeepwm69
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Distributor cap question

When I ran new looming on the underhood wires, I took the distributor cap off to give me room to work. I'm wondering if I didn't get it back on exactly straight. The truck runs ok, but tends to bog a little more easily in higher gears than I'm used to. On my Jeeps there is a clamp that holds the distributor in place and one rotates the distributor to change timing. The cap is keyed so it will only go on exactly straight.

I had trouble getting the cap in place where all the retaining clips would hold it down on this truck. Could I have possibly not gotten it quite lined up and thrown the timing off a hair?
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Old 02-12-2015, 03:42 PM   #2
enaberif
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Re: Distributor cap question

You should always mark distributor to base to ensure it goes back on the same way. You can take a cap off and on all day long and nothing will change. But if you take that cap off and rotate it 90 degrees your timing will be way out of whack.
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Old 02-12-2015, 03:48 PM   #3
motornut
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Re: Distributor cap question

The caps I get are keyed.
Isn't yours?
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Old 02-12-2015, 03:52 PM   #4
Jeepwm69
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Re: Distributor cap question

Quote:
Originally Posted by enaberif View Post
You should always mark distributor to base to ensure it goes back on the same way. You can take a cap off and on all day long and nothing will change. But if you take that cap off and rotate it 90 degrees your timing will be way out of whack.
I know I didn't rotate it 90 degrees. Just unhooked the cap and clipped it towards the front of the engine to get to the wires routed along the top of the engine along the back.

I'll take it back off and check to make sure it's lined up correctly, but I didn't figure the clips would work if the cap wasn't in the proper place.
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Old 02-12-2015, 05:35 PM   #5
Bigstevex4
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Re: Distributor cap question

There almost imposable to get on in wrong position and have them run.
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Old 02-13-2015, 08:31 AM   #6
Corts60
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Re: Distributor cap question

Did you accidentally disconnect the vacuum advance? That's what this sounds like.
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Old 02-13-2015, 12:45 PM   #7
Dead Parrot
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Re: Distributor cap question

Another thing to check is make sure the little button in the center of the cap is still in good shape. If the cap is several years old, removing and replacing might have killed an already near end of life button.
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Old 02-13-2015, 01:04 PM   #8
Jeepwm69
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Re: Distributor cap question

By button do you mean the rotor?

I did noticed a line came off of the EGR, and when I tried to hook it back up it was rotted to all getout. I'll check the vacuum advance. Need to go over the whole truck and run new vacuum lines. The ones on there are all original from 1983
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Old 02-13-2015, 10:28 PM   #9
reporter000001
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Re: Distributor cap question

prob ur vac advance, spray wd-40 on the hose barb connections, if idle changes, its leaking

hahahahah! -----ive done this before, if ithe cap is slightly off, it will hit and grind itself, pop the cap and look for smack marks, if none, alls clean, check for corosion, always do cap and rotor together.

if still all is good, check the advance springs, one may be out of wack or stuck, play with it with yourfingers, CAREFULLY a blow gun always does the job for me, second, if that little feeling in your body says this aint right, it prob aint, if ur using cheap parts the casting is prob off, esp if its an hei push down j hook desighn.

go to napa or summit or jegs and use their products.

lastly, with the cap removed, pull up and down, left and right on the dist. shaft..CAREFULLY it should have VERY little play. lastly check the dist. hold down bolt on the manifold, its possible it was lose and the entire unit spun, thus retarding timing.

check the "+" to the hei make sure its good, multimeter it.
check ALL spark wire connections.

a resistor type plug with poor connection will preform "normal" at idle and malfunction at high rpm due to optominal voltage not being reached.....

a test light will not show this.... pull all plugs and read them.
all just guesses.... let me know.


btw- the guy that said button, he means the carbon button on a spring under the coil.

Last edited by reporter000001; 02-13-2015 at 10:42 PM.
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