I am getting no spark with a GM HEI set up. Replaced cap, coil, rotor. Finally I checked to make sure that the dizzy was spinning. It was not.
I pulled distributor, and gears in the engine are worn down to nothing. How hard is it to replace that gear? The jeep was at a mechanic not to long ago and I think they replaced the distributor. But I don't think that the gear is the right one for the AMC engine. Backwards.
Search HEI and gear in the forum and you will get lots of info. I'm afraid most will be bad for you.
The gear in the engine is part of the cam shaft. It will need to be changed and then the proper gear put on the dizzy to match the composition of the cam and cam gear.
You are not the only one to have this problem after a HEI swap. Also in my experience when you get the HEI out of a big six GM engine and put the gear on off a V8 AMC dizzy the gear isn't even close to being centered on the camshaft.
Thanks for the replies. I searched for this problem but am not finding a lot of info. I'll keep looking. I guess I am going to have to pull camshaft. Is the gear removable or is it built into the shaft. I've never pulled a cam shaft before. But Ill read through the forums and see if I can't figure it out.
absolutely the best way to go about this is to remove the " GM" distributor and throw the M******* away.
Buy a DuraSpark stock distributor and build it up "JeepHammer" style and use a GM module and Ford coil.
No more gear problems.
Your Jeep will never be reliable as it is now.
Cam has distributor gear cast and machined in the center of cam and not replaceable like the v8.
Gonna have to replace cam and will actually be easier to just pull the engine out, do it right, and reinstall.
Do NOT attempt to just run a new distributor on the old cam gear.
If it's good TO you, it's gotta be good FOR you....
I put the motorcraft dizzy back in and put a MSD I already had on it. Then ripped the HEI module out of the GM dizzy and made a stealth HEI using the dead duraspark box which is what started the whole HEI experiment in the first place.
Lots of opinions, and we don't know a thing about this Jeep, other than it's a CJ and you have an HEI.
What engine? What brand HEI? Care to share?
There was a problem awhile back with aftermarket HEI's, where they came with a gear that was hardened...too hard. And it ate up the gears on the cam.
It is possible you got one that was still on the shelf with the bad gears. Most of them have filtered through the system by now.
So IF that is what happened to yours, then you'd need to pull the cam. Then put the correct gear on the distributor so it won't do it again. No need to change it, the HEI is a great unit, used on millions of vehicles.
What is fishy is your statement
The jeep was at a mechanic not to long ago and I think they replaced the distributor. But I don't think that the gear is the right one for the AMC engine. Backwards.
You THINK they replaced the distributor? So did they, or didn't they? If they did, then THEY are responsible for your cam gear, and I'd be taking it straight to them.
And I'd inform them about the gear issues and to make sure whatever unit they use has the correct gear. I believe you can still get AMC factory gears at the dealer, plus there are a few aftermarket places that sell them, too.
Plus, find out exactly what brand they used, might be some recourse there, too.
I asked a ref if he could give me a technical foul for thinking bad things about him. He said, of course not. I said, well, I think you stink. And he gave me a technical. You can't trust em. -
Thanks for the replies and sorry for the lack of information. The jeep belongs to my girlfriend. Her ex decided to rebuild the engine, it was almost done - they had a falling out and he didn't complete it. She took it to several mechanics each one threw new pieces in here and there... Charged her a lot of money, but never really fixed it. So the jeep has been sitting at her parents house in Texas for the last year. We went down to pick it up (the last mechanic said he got it running, it was running just a little rich) and it needs work.
The biggest problem is no one really knows what is going on with it. It's a old vehicle with no history. The engine has been rebuilt (I've seen pictures) and it has a lot of after market mods on it. The jeep is a 6 cyl 4.2
The last couple of days I've been working on a Howell TFI problem. I think I got that figure out then this lack of spark problem happened.
I don't know what type of distributor it has in it. But it does not look new. I am trying to dig up the information to see if the mechanics did in fact change it, or at least charged us for it.
So the cam shaft replacement on this engine is basically taking it all apart, right?
Again, I appriciate your help, and sorry for the lack of information.
You need the AMC V8 gear for the end of the shaft. Sounds like some bloke put a stock GM dizzy in there and "made" it fit somehow. I love my HEI system on my 258. Some of the best money I've ever spent on my jeep.
Pulled the camshaft. It was fairly easy to do keeping the engine in the jeep. Pulled grill, radiator, valve cover, head, timing cover, timing chain, push rods, rocker arms, and lifters. Cam slid right out.
As expected the distributor gear was ground to almost nothing. Parts place ordering a new shaft should get it tomorrow.
Now I need to figure out what to do about the distributor. A big part of me wants to just drop in a stock distributor, but I would need to buy all of the stuff, where I have a brand-new cap, coil, rotor for the HEI setup.
I am going to go through and read the forums to try to decide what to do. I am sure there is a ocean of information out there about the HEI distributor. I do have one question off the bat, if I would to go with a "AMC 258 HEI distributor" from a third party, that is just a drop in, with the correct gear? Is that the only difference?
one thing to think about.........since you have already pulled so much off it, consider this: if you pull the oil pan off it, you can actually SEE how the distributor gear/cam gear (and also the oil pump drive ) mate up and if too high or low can make the appropriate changes with no guesswork. This is an advantage that the V8 guys don't have. To be damn sure the problem is solved, especially if using anything but bone-stock distributor, I would.
Also give you a chance to possibly get some of the metal out of the pan and might as well put an oil pump in it (25 bucks, 15 minutes).
If it's good TO you, it's gotta be good FOR you....
Great idea. I'll pull it tomorrow when I'm waiting for the camshaft to get here. Half tempted to just pay the money for a DUI and be done with it. From what I read that is just a drop in, with a good gear. Like previous stated I have no history on anything, and the current distributor looks old. I am really hesitant to drop it back in - regardless as if I change the gear (which I think is a given).
MSD makes a gear that you could use. It needs to be for any 78-91 AMC V8.
That distributor was probably one of the HEI clones that come with a hardened gear. They are known to eat drive gears. The MSD gear is not a hardened gear.
There's a crap-ton of info on this forum in regard to this problem. Most of it resides with "clone" GM HEI distributors. I've had a factory GM HEI in my CJ5 since 1997 without the slightest hint of problems.