Plagued Cam bearing in distributor gear failures

[dwg86]

The block with the cam plate is the later model block. When I built my stroker, I used a solid pin instead of the spring and pin. I put the timing cover on with the cam and cam gear bolted on. I took the rear plug out behind the cam and used a dial indicator to read the distance from the cam pushed against the block and to the cam pushed against the timing cover. I then made a pin that stuck out past the cam bolt the distance I measured minus .003. Someone else on here was having cam bearing problems (silverxj). He had a cam company bring him a custom cam using the newer style cam. He used the cam plate and factory style timing chain and had no more problems.

[Cheromaniac]

I built my stroker on a '00 block with my original stock '92 cam, 00' timing cover, stock '94-'98 timing set, stock distributor with gear, and used the recessed bolt/spring/pin. Never had a problem in 86k miles.
More problems seem to occur when people deviate further away from using stock parts.

[dwg86]

The block with the cam plate is the later model block. When I built my stroker, I used a solid pin instead of the spring and pin. I put the timing cover on with the cam and cam gear bolted on. I took the rear plug out behind the cam and used a dial indicator to read the distance from the cam pushed against the block and to the cam pushed against the timing cover. I then made a pin that stuck out past the cam bolt the distance I measured minus .003. Someone else on here was having cam bearing problems (silverxj). He had a cam company bring him a custom cam using the newer style cam. He used the cam plate and factory style timing chain and had no more problems.

That was supposed to say “grind him a cam” not bring.

[Russ Pottenger]

The block casting number 53010449 covered years 99 to 03 that included the last three years of the XJ.

It took a few years for jeep to run through their inventory of nipple timing covers.

The later retainer plate cam is available for those that wish to retain that style cam. If you use the early style cam that utilizes the pin and spring it’ll need to be used with the early nipple style timing cover.

[Tolemar]

So after lots of research and thought I ended up going with a Comp Cam retainer plate style and ground on a wide lobe (I think melling) core that Russ had in stock. I had Russ get me the more expensive melling timing set that I believe is what the factory uses. Imo it’s looks better made and finished than the aftermarket one we compared it too. I am going to run a standard melling pump also. With that said I personally think the issue is cam walk and it seems to follow the spring pin setups. It could be maybe the wrong or weaker spring wrong length pin even the cover without a nipple. Who knows but I’m going with what I know works. Back in 2006 I built twin 572 ci 1250hp blown big block boat engines for my buddy with HUGE hydraulic roller cams also use a retainer plate cam and have yet to have any issues with even bronze distributer gears with countless hours on them. Still run flawless to this day.

[Tolemar]

I am just wondering . Has anybody ever measured to see if there is a difference in the early and late model blocks specifically where the top timing gear sprocket rides against the block? Obviously there is a difference in the timing sprockets between the early style cam spring button style and the later cam retainer style sprocket. The button style timing sprocket rides on the front of block. The retainer style timing sprocket rides on the cam retainer plate. I know the cams are different with the front of the retainer cam cut back a bit to clear the retaining plate. But has anybody actually measured it? To many failures with the common issue being the double dollar timing chains on the later model blocks. The pic is the difference in cams. The retainer plate and sprocket are on the late model stock bump stick. The other one is the early style bullet racing cam I’m not going to use anymore.