Defender Source Forum banner

1 - 20 of 23 Posts

·
Premium Member
Joined
·
89 Posts
Discussion Starter #1
I just installed a new Pertronix distributor on 1992 RRC. its NOT the expensive performance one, its the direct replacement one...anyways, after installing it i adjusted the timing to 6* BTDC, but when i check it whit a timing light it looks erratic and shifts up and down (vacuum advance disconnected) when I connect the vacuum advance I cant rev the engine. If the engine is revved past 1,000 RPM it will begin to miss and backfire. Has anybody had any problems installing these distributors? Why would the vacuum advance cause it to miss and backfire? I was adjusting it all day yesterday and the only way i got it to run semi decent is with the advance disconnected and the timing still shifts a little...

-Gabe.
 

·
Premium Member
Joined
·
13,802 Posts
Ensure it's not 180 degrees off.
scratch that the truck wouldn't start if it was 180 out.

Are you sure the distributor you installed is a vacuum advance ?
Some distributors have a vacuum retard to idle down. The dwell being all over sounds like a bigger problem. I'd try loosening the distributor clamp and turning the distributor to find the sweet spot. I usually time cars by ear anyway.
 

·
Premium Member
Joined
·
13,802 Posts
I tried timing it by ear, but end up with the same problem timing shifts between 1 and 3 degrees in both directions...
if this a v8, a worn/stretched timing chain, something the early ones were known for, will make it damn near impossible to set the timing. Any idea if the timing chain and gears have been replaced ?
If you go to replace yours I'd suggest the Cloyes dual roller setup.
 

·
Premium Member
Joined
·
874 Posts
Sounds like you've got a couple of wires out of sequence. Check that firing order again.
 

·
Premium Member
Joined
·
89 Posts
Discussion Starter #8
Sounds like you've got a couple of wires out of sequence. Check that firing order again.
It runs smooth until i hook the advance. I think if i was off sequence it would be hesitant all the time.

The timing chain is original to the car V8 3.9L engine with 145,000 miles...
 

·
Premium Member
Joined
·
409 Posts
Sounds like you have everything covered. If this was the original or old distributor I would open it up and make sure everything is ok. As its a new one return it and get a new one. It wouldn't be the first brand new faulty part.
 

·
Premium Member
Joined
·
89 Posts
Discussion Starter #11
I have not contacted Pertonix yet. I wanted to make sure I did as much as I can before resulting to that. I checked the air gap on the new distributor and it was large. Like over 0.040" I used a plastic gauge to adjust it to 0.010" which made the engine start, but now i have the timing issue...
 

·
Registered
Joined
·
1,207 Posts
Have you checked the new vacuum advance to see if it's holding vacuum? You do have the vac hose connected to the correct nipple right?
 

·
Premium Member
Joined
·
89 Posts
Discussion Starter #15
The vacuum hose is connected to the small nipple above the throttle body. I can create a vacuum in the hose and hear the diaphragm move inside the dizzy and hold the vacuum...
 

·
Registered
Joined
·
1,207 Posts
I should have been more clear regarding the vac hose. I'm referring to the connection on the vacuum advance.... there's two options. You want the outside one. Just trying to rule out simple things.
Mechanical advance working?
Did you check that the timing is advancing with throttle?
 

·
Premium Member
Joined
·
89 Posts
Discussion Starter #17
Oh sorry. Yes it is hooked to the outside port of the distributor. Im not sure about how much it advances. Ill check it with the light when i get home this afternoon...
 

·
Registered
Joined
·
1,207 Posts
I have not contacted Pertonix yet. I wanted to make sure I did as much as I can before resulting to that. I checked the air gap on the new distributor and it was large. Like over 0.040" I used a plastic gauge to adjust it to 0.010" which made the engine start, but now i have the timing issue...
I'm wondering if the original air gap was proper. All of my searching shows it using a larger gap. Maybe your timing was way off & that's why you got a no start.

I'm also curious if your idle is steady or fluctuating causing 1-3º timing swing... or a vacuum leak.

All my curiosity is because I've been thinking of doing a Pertronix too.
 

·
Premium Member
Joined
·
89 Posts
Discussion Starter #20
I just got off the phone with a local Rover mechanic. he said they are plug and play. didn't go into a lot of detail, but said he hasn't had any problems with it. I will look at the whole ignition system this afternoon, try to trace vacuum or air leaks and see if i can get it steady.
 
1 - 20 of 23 Posts
Top