More dist. gear wear issues! His rear cam plug shouldn't come into play, unless it was located way too deep. Cam shoulder should be contacting block face. Yes Larry, See what his resolution was.....
Ethan, I'm going to remove rockers to unload cam, remove chain, put eccentric and new cam gear back on cam snout, leave key out of keyway, put cam bolt back in loosely. Install cover. Then I'll be able to drop dist in, rotate it and feel any bind or resistance, i.e. tight or loose spots. I'll do that check with cam in 1/4 rotation increments. Should tell me something? Then I'll put key back in and use dist to rotate cam by hand to check mesh. Oil pump turns super smooth so that won't be a factor. This shouldn't be a complicated issue, geeze, we're just talking about gear mesh and centerline axis. It's either correct or its not. First, I need a new MSD gear though.
I'd consider applying gear marker 360* around a fresh cam gear and install a fresh stock dist. gear and see how they mesh. You can just reuse the original gasket(if you didn't clean it off) and temporarily install the cover. No glue necessary. No balancer necessary. A cold engine and thick oil is good because you want the distributer gear loaded by the oil pump. I'd prime the pump, install the distributer, and crank the engine over by the starter a few revolutions, no starting the engine necessary. Pop it apart and see what the gears look like. You may want to try marking the cam gear the first time and then pop the cover off and take a look at it. Then clean the cam gear, apply marker to the distributer gear 360*, do the same cranking procedure, and then check out how the dist. gear is marked. Unlike a typical rear gear check you want to see how the gears mesh for 360*. You may want to try it with a stock distributer just to see how it works. https://www.summitracing.com/parts/...9uOFLxMTVz8YgnPe9DQh60t8mQnKIDYEaAqWbEALw_wcB The BOP gear probably will work but it is not a "hardened" gear but a sacrificial one like the bronze but unlike the bronze the tiny plastic particle wear material can not really damage an engine. Also I would say the evidence of your original standard hydraulic cam/timing cover/distributer not showing signs of wear after thousands of miles does sort of point to the new addition to the engine, the roller cam which may be machined slightly off.
Preliminary inspection only shows a .001-.0015 run out on snout and a .001 or less on shoulder. I will check assembled after stack up of all components. Good ideas Mike. Cover still has gasket on it. I just need a new gear. I have gear marking compound. Oh, cam is nice fit in bearings, turns smooth as silk, no bobbling can be detected. I think I'm done for today, Bud Light time!....Dilly Dilly
I'll call Mike @ T/A tomorrow and see if a hardened gear like Larry suggested is even an option. May have to end up with the same MSD gear? We gotta be able to get more than a couple K on a dist gear I would hope. This is a needle in a haystack hunt for the remedy.! Much thanks to everyone for their input!
Quick thought.....how tight can I set cam end play since timing cover is aluminum and will expand? .002 maybe? It would keep the gear wear to a minimum.
it would be better if the latter oil pump systems could be incorporated into the older t/c's. it would cut the drag down by half. but will it alleviate the issue if a t/c dist hole was machine off location which could/would cause the gear wear from happening and/or not lining up. don't forget, tolerances will add up over a multitude of machining dimensions. looking at all the dist's I have, this wear does not happen in a stock engine. only when cam/oilpump changes are made. and wondering if when hi rpm's are happening, valve train vibration and drag isn't also contributing to gear wear.
I hear you John. .001 runout at snout dia, plus .001 shoulder runout, stacked up and measured at cam gear dia. could be maybe .005 wobble. Then add in the .005 cam end play and you have a lapping machine going on. I'm going to talk to TA about this. Maybe endplay can be reduced to .002? Also adding gear oiler would keep things slippery. I don't have a flat tappet cam here, is there an angled oil hole to weep oil on gear? Billit rollers have no such hole. You wouldn't think an extra 1k or 1.5k rpm would cause major gear wear in such a short time/ miles. Stock stuff lasts over 100k! Gotta get this under control.....
fuel pump cam has to be installed like this. If other way around or backwards the issue you have will result . Dan
Dan, That's exactly how I assembled it. There is an 'F' on fuel pump eccentric that maybe means forward or front. No noticeable wear on pump arm or eccentric. Talked with Tim @ TA, Mike wasn't in, he says they have been drilling a 1/32" hole on an angle at the two gears, into the oil galley plug to produce a oil spray on the 455's. I'll try calling Mike again in a bit.
another possible cause is tightening of the t/c bolts to the block and oil pan. the t/c is just thin junk aluminum molded to gm specs. it will move when tightening the bolts. a billet part would be nice,but........then the block would have be billet too. tolerances would have to be in tenths so the accumulated tolerances would not be high. now we're talking aircraft quality. lol the best fix for the whole problem is the latter v6 oil pump set up that runs off the c/shaft and distributorless ignition. this would be good for the young'ns as I prefer the old uncomplicated stuff.
John, I rigged up this custom cam bumper and button that is threaded thru the t/c and I adjust cam endplay after t/ c is torqued down. So I get a real accurate measurement. Fine thread, locknut is (you're gunna love this) JB welded to seal water out and oil in after setting play. I'm thinking about .002 endplay because I can control endplay so well. button inside & out, ground & polished cam bolt ^ Maybe I'll get another 25 or so miles out of the dist gear.
Talked to Steve today. He told me he ended up replacing the timing cover and that resolved his issue. It was a TA cover that he had to replace.
the dizzie. your going have to live with it. unless you find the magic secret somewhere as to make the parts live longer. same engine, different questions. what rpm's have you been hitting this year? have you inspected ALL your bearings for wear? oil and bearing clearance will make a difference in bearing wear. I should know, been there, replaced them all. lol just for old age memory, the 1.88's we run @ 7k, the machine shop the date on the crank was 2008. I thought it was only 3 or 4 yrs. its 9 yrs on the 1.88's(YIKES) and will just polish the crank. I used plain 10-30 amsoil, not race oil.
Well hopefully a GM cover is in good alignment with a billit MSD. Demko was saying his TA cover was slightly off or tight. No trouble with the Voodoo cam @ 4,5k miles with this same cover & dist.
