Camshaft "distributor Drive Gear" chewed

New on here, sorry if in the wrong section / know it's been beat to death (subject) as well, but hoping wont bother you all too much... :physassult:

Anyhow, I have a 1974 CJ5 with AMC 304 V-8. I installed a DUI distributor from Summit after being assured that the distributor gear was fine for use with OEM Cam gear. Well 9 months later it finally gave, onn Loon Lk rd (ribicon) of all places... in the snow... (longer than I've read on others stories...)

I have ordered up a "matched set" and a upper and lower gasket kit for the 304, and am waiting till all arrives before tearing into the engine.

Any suggestions on what to look for would be greatly appreciated.

I assume I will take off the timing cover / water pump section and replace gear, checking timing chain while in there (never have since buying) and look for excess debris as well. Also will be dropping the oil pan, and inspecting / cleaning, removing intake and heads to have a look at the cylinder walls and rings etc...

I plan to install a new filter and flush the system with new oil and filter, then remove and replace with new fluid and filter again. Suggestions on methods for this also welcome, though I have an idea of how.

Link on the gear set I bought (yeah I know your "bulltear" would be better, but not in the budget at this time...) http://www.summitracing.com/parts/OMX-1742303 Plus summit decided to help with the replacement costs for customer relations reasons... :wink:

thanks all :occasion5:,
~ JR

Welcome to Bulltear!

Sounds like you have it covered. I really don't know how they can assure you the cam gear will work. There are at least 3 known "flavors" of gears, each with a slightly different pitch, so it's hard to know which one is in your engine. The best thing to have done would have been to transfer over the gear from your original distributor, that's why a lot of AMC distributors are sold without a gear.

Since it's too late for that, go with your plan. Clean everything out well, including cleaning the oil pump. Coat the oil pump and the new gears with assembly lube when you re-install them, and spin the pump with a priming tool before dropping in the distributor.

A worn timing chain can allow the cam to walk forward. Look for a mark inside the timing cover from the cam bolt touching. Replace the timing set regardless, it's cheap insurance.

I love the Rubicon. Ran it twice, first in 2000, again in 2002, both times in late fall, after Labor Day. Did 3 day trips both times, camped at Spider Lake and Rubicon Springs.

Let us know how it goes.

Bob
tufcj

Thanks Bob! Do you by chance have any links that are good for doing the oil pump flush? I'm sure I can find, but figure you may know some of the better ones.

I'll post up some pics and updates.

Thanks Again!

~ JR

The oil pump is pretty much just taking the oil filter adapter off the timing cover, flushing the passages with brake cleaner, coating the gears with assembly lube and putting the cover back on. If the oil filter adapter has any deep scoring where the gears ride, you can lap it with some fine emery cloth on a piece of glass, or install one of Bulltear's mid-plates. I run the mid-plate in all my engines, so the oil pump is running against a metal plate instead of aluminum housing.

Bob
tufcj

Thanks Again Bob!

I'll be tearing into it this weekend. Will post up some pictures and such next week.

Cheers!
~ JR

Any info?