I'm running a Mopar slant six in my '35 Plymouth sedan and back in April I had it rebuilt by a reputable engine builder. I installed it and broke in the cam, then I was ready to drive it for the cruise part of the year. I had a problem with the brakes, so I took it out to test them, at 60 mph on the highway, I heard a loud pop and it just died. I towed it home and pulled the distributor, the plastic gear was completely stipped of teeth. I have since replaced the gear two other times with the same results, after only less than 100 miles on the engine. I've contacted the engine builder and the cam manufacturer about this but no one seems to have definite clues to what is wrong. Hoping somebody here does. HELP, I'm getting desperate after not having a ride all summer. By the way, I'm running a three deuce manifold w/chrome 97s, headers and alot of chrome and it looks pretty awesome, but don't run very long at a time.
had plastic gear on my 61 slanted six distributor. it was the plastic ring and pinion that had me baffled.
I'm not a slant six guy, but I assume that gear drives the oil pump also? If so, and if you know the distributor shaft is not too tight, then maybe feel the oil pump drag, or see if the pump relief is set way too high?
I always loved the slant sixes. I had on in a '64 Valiant, factory four speed with factory Hurst shifter. Loved the car. Yes, the gears are "plastic" (nylon). Regarding your problem a couple things come to mind. The gear is not meshing right so it could be that the shaft is bent, the gear is not installed in the right place on the shaft (Some of the replacement ones ask you to drill your own hole for the cross pin. Check end play), the "plastic" is defective (try a different brand). Good luck. Send pics. Love to see it.
I appreciate all the responses. The distributor gear runs off the front side of the cam gear, and the oil pump runs off of the back side, they really don't have anything to do with each other. I would love to get a metal gear, but I can't find one around these parts. If anyone knows where to get one, please let me know. jimbousman, I eliminated all but .005 end play in the shaft and drilled my own holes and they are straight, but when this happens, it wipes the teeth clean off of the gear. But just replacing the gear doesn't really tell me why this is happening, like a smart guy told me, they made millions of these engines and didn't have this problem.
Been a while since I worked on one of these but I remember how frustrated I was every time I had to change points with the engine leaning against the fender well. It got to the point I pulled the distributer to bench change the points. anyway as I recall there were spacers between the gear and the distributer stem. Not sure how many or how thick but if they are missing the gear might not mesh right.
When I was a kid my mom and dad had a 71 dart with a 225 slant 6. One day it dies and I get my little tool box out of the trunk and start looking around. I see there is no spark so I take the cap off and tell her to crank it. The rotor did not turn. We had it towed to the house and I pulled the distributor out and the plastic gear was wiped out. While my dad called around for a distributor I keep messing around with the car and I figured I would check the oil. I pull the dip stick out and it is broken off just a little above the markings. It was somewhat bent like the crank had been hitting it. I put in the new distributor and later got a new dip stick but not long after the gear got wiped out again and the dip stick was broke also. All I can imagine was the dip stick was just able to touch the crank or rod and it was braking it off and the broken pc. of the stick went through the gear. I fished the broken pcs. out with a magnet when I changed the oil and only used the good dip stick to check the oil, the new distributor held up for years after that. It sounds as crazy today as it did back then, but it happened.
JC Sparks, whenever I pull the oilpan there is nothing else wrong, just little plastic bits and pieces and I'm changeing the oil and cleaning everything each time( its getting expensive in oil changes). Isettajohn, thats going to be my next move, thanks.
Ebbsspeed, my thinking is maybe its the distributor problem, but I doubt that as I ran this dist. in the same engine before the rebuild, but I'm running out of ideas. Could it be the cam is walking front and back?
I also had this problem, i replaced that gear several times. As it turns out the dizzy had a hard spot in its rotation (bad bearing maybe). Replaced the dizzy and it never happened again.
By the way, I'm running a three deuce manifold w/chrome 97s, headers and alot of chrome and it looks pretty awesome, but don't run very long at a time.[/QUOTE] i might need to see this! post a picture or two.
Guys, as soon as I can figure out how to post pictures, I will. Even if this thread dies, I'll get pics here sometime, I promise.
at the top of the page on the left there's a box "post replys"click it. then type whatever you want to say, then scroll down a bit to "manage attachments" click that.a window pops up with lines and the word "browse" click that. it will connect to your computer's photos. look through them and pick one. click on the photo, then hit "open".do another one if you like. when you're done hit "submit" at the bottom of the page. make us proud!
Thanks go-twichy, I appreciate the pic lesson, and I WILL post pics tomorrow, but I have to go for tonight. Everybody keep coming up with ideas to my problem.
Bitch'in choice for a project "Zipoleon". I just dragged my 31' Dodge sedan project home Couple weeks ago also. The plan was to drop a 250 Chevy and 3 speed trans into it, but when my "Mopar blooded" friend found out what i was going to do he freaked! He said "at least keep it all mopar, and the slant sixes that hard to run down anyway". He was right, i had run down a 170 with low miles, and a 904 trans within a couple weeks for a mure $250.00! (He's a buddy of our club.) Can't wait to see your pics! Heres mine.
somebody took the time to walk me through it, i'll do the same. but i do want to see your slant six with 97's! so my reasons were selfish.
Try putting a new plastic gear on the dist, and then paint it with a permanant marker. Run the engine a little bit, and pull the dist and look for the wear pattern. The new cam scares me. The gear worked for many people for over 100,000mi. It should give you better life than you are getting. You might also want to check with the camshaft companies. Hardened camshafts eat dist gears, and there are bronze gears for most engines. Good luck.
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