distributor and camshaft don't mesh right

[Ivan D.]

Well I'm almost ready to drop my new intake and carb in, so I pulled the old intake and carb tonight, then accidentally looked at the distributor gear and immediately got that "oh ****" feeling - the gear seems really worn out on the edges where the camshaft pushes on to make the distributor rotate. I grab my LED mini flashlight, crawl over the engine, and shine down the distributor hole - sure enough, there are wear marks on the camshaft too, just not as bad as those on the distributor gear. Again camshaft marks are on the edges that push on the distributor gear. I'd make sense if the camshaft is slightly more forward than it needs to be, however that's damn near impossible considering the fact I have a button in the front to prevent it from doing just that. If the camshaft was too much behind the other edge would wear out... So I'm wondering, what causes that wear? I have over 60psi of oil pressure all the time, might drop down to like 45 when hot and idling in gear at a stop light, but it hardly ever happens. So there is plenty of oil getting up there, and the camshaft lobes don't look bad at all... Any ideas?

[grinch4om]

what kind of cam? a roller needs a different gear , check withe cam manufacturer

[Ivan D.]

Not a roller, it's a Melling towing/RV cam for use with hydraulic flat tapped lifters. Roller cams require a steel gear (vs. iron for flat tappets), so if a roller cam is meshing with an iron distributor gear it will destroy the distributor gear without sustaining any damage to itself. My cam however has visible marks in its own gear, so that's not the case... Weird thing is I just looked at my old cam, and its gear is worn exactly the same way, so the distributor must have been meshing like that for quite a while. By the way the engine has less than 300 miles on new crank, bearings, oil pump, timing set, and cam and lifters and pushrods, and It has no problem whatsoever pegging the oil pressure gage at 1500rpms hot.

[grinch4om]

clean off the gears, apply some prussion blue to the gear on the dist,(used for checking ring and pinion depth) turn the motor over and see where exactly the teeth mesh , to high, you may need to trim the bottom surface of the dist or try another one

[porpaintt]

It might be that you have a high pressure pump instead of a high volume pump.The pegging of the gauge suggests that. They will make the gears wear very quick. (Just a thought, been there done that)

[Ivan D.]

It's actually a high volume pump, not a hight pressure one, but still it's supposed to put out about 70psi - dunno what psi the high pressure ones reach, but that's data off Melling's site, and each of their high-volume pumps is about the same. But I think I might have found the culprit, it's kinda grinch4om siggested - the distributor's gasket was mighty thick, the new one I just put in was much thinner, and from what I've seen that's what it's supposed to look like.