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amcjunky
02-15-2010, 08:58 PM
ok so i am going to post some pictures of the couple sets of cam and dizzy gear that got chewed up in my motor. I know that oilling was not the issue because i had between 40psi at idle and 80psi at high rpm and i had the little hole drill above my dizzy for extra oiling
http://i43.photobucket.com/albums/e353/pongopig/dizzyoiling.jpg

so my question is what else could have caused this. if i order the matched cam gears and new timing cover from bulltear will that fix it? i use a msd dist ( the amc style one).

http://i43.photobucket.com/albums/e353/pongopig/IMG_0047.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0048.jpg

http://i43.photobucket.com/albums/e353/pongopig/IMG_0049.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0050.jpg

these two were a set both amc brand gears

http://i43.photobucket.com/albums/e353/pongopig/IMG_0051.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0052.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0053.jpg

http://i43.photobucket.com/albums/e353/pongopig/IMG_0055.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0056.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0057.jpg
http://i43.photobucket.com/albums/e353/pongopig/IMG_0058.jpg

and these two were a set the dizzy gear was msd and the other one cam with the motor

the first set lasty say 5 or 6 pass down the track and the second last 10 -15 can exactly remeber

i hope you guys can give me some help in figuing this out

thanks justin

tufcj
02-16-2010, 10:06 AM
Several things.

Do you have the positioning dowels in place for the timing cover? They are critical for the proper alignment of the gears.

The dizzy gears drive the oil pump, too much pressure puts too much strain on the gears. My AMX ate a set with pressure similar to yours. I went back to a standard pressure relief spring when I replaced the gears and haven't had a problem since. Also make sure the relief plunger is in right (point forward), and it moves smoothly in the bore.

Gears. They MUST be a matched set. There are at least 3 different known tooth pitches used by different manufacturers. Different mismatched pitches = extreme wear. I think the MSD gear is a variant of a Chevy gear.

Make sure the oil slot in the upper cam gear is open. A lot were blocked by casting flash. This feeds oil from the front cam bearing thru to the inside of the dizzy gear. There's more than enough oil flow if this passage is open.

Bob
tufcj

amcjunky
02-16-2010, 05:41 PM
yes both dowel pins are there and i never built this motor i bought it as a whole. i will check the relief plunger tonight

thanks justin

jeepsr4ever
02-18-2010, 06:58 PM
Turn pump by hand with a screwdriver. Pump should turn easily. Also check relation to distributor to T cover when it is all the way down and in and make sure you dont have a gap on the distributor.

Mudrat
02-20-2010, 03:42 AM
Turn pump by hand with a screwdriver. Pump should turn easily. ... .

Caveat that :mrgreen: - should turn easily if NOT filled with notoil!!

Once the engine is all together and the system filled with oil, it takes a heck of a drill motor to keep turning the pump. :shock:

jeep_man_401
02-21-2010, 01:42 PM
I had same MSD dissy in a new rebuild and used the old cam gear. I ended up with the same results. Ordered a set of Bulltear gears and have not had a problem since! :lo1l: I did have the oil pressure spike and blow the oil filter gasket but I think the plunger got stuck with crap from the gears going bad. Anybody pull the pan and look at the mains & rods after chewing a set of gears??

Like the water pump!

While u have the MSD apart, pull the plate for the pick-up coil and put some epoxy on the screw on the back side. My coil/pick-up went bad and you have to pull the whole dissy apart because the screw comes in from the back side and u can't tighten it from the top. You'll see when you tear it apart. A real time saver later on....

jeepsr4ever
02-22-2010, 09:08 AM
Turn pump by hand with a screwdriver. Pump should turn easily. ... .

Caveat that :mrgreen: - should turn easily if NOT filled with notoil!!

Once the engine is all together and the system filled with oil, it takes a heck of a drill motor to keep turning the pump. :shock:

No, turning with a screwdriver will not prime the pump. Even after you prime it turning with a screwdriver should be easy. Priming eats 1/3hp drills for breakfast =D> :oops:

amcjunky
02-24-2010, 06:54 PM
here at the last main and #8 connecting rod bearing

http://i43.photobucket.com/albums/e353/pongopig/18037_396640015506_780350506_104163.jpg
http://i43.photobucket.com/albums/e353/pongopig/18037_396640060506_780350506_104163.jpg

also i had a anti cam walk plate in there
http://i43.photobucket.com/albums/e353/pongopig/my%20javelin/18037_396599060506_780350506_104158.jpg
http://i43.photobucket.com/albums/e353/pongopig/my%20javelin/18037_396599065506_780350506_104158.jpg

would that have affected anything?

i am going to buy a new timing cover and gear set from bull tear when i get the money is there anything else i should be checking?

thanks for the help guys

Mudrat
02-25-2010, 03:58 AM
No, turning with a screwdriver will not prime the pump. Even after you prime it turning with a screwdriver should be easy. Priming eats 1/3hp drills for breakfast =D> :oops:
REALLY?? Once installed it takes a gorilla with a screwdriver or at least a 1/2 HP drill to spin the pump to get pressure???
It’ll spin with a driver, but won’t bring the system to pressure. And I’m thinking I may need to find my BT Priming Tool when I get back since it will have been 3 months since running my engine. :-| #-o

ironman_gq
02-25-2010, 11:13 AM
I took apart my original dizzy and took the gear off and spin that with the drill to prime my pump. works really well as long as I dont push down which can drive the pump rotors into the housing and cause its own problems.

jeep_man_401
02-25-2010, 03:28 PM
This is what I did..pulled everything apart, washed everything and brushed all the passages replaced the cam bearings, checked cam & lifters replaced mains and rods. :smile: But I'm picky about a clean engine inside. Those bearings look toasted to me...my guess is the cam bearings are bad also as those get the oil first.

jinpdx
02-26-2010, 02:05 AM
If the metal shavings are able to go through the engine via the oiling system, what is the point of an oil filter?

jeep_man_401
02-26-2010, 04:33 AM
Cut the filter open and look inside...

jinpdx
02-26-2010, 01:14 PM
My only point being is the filter should stop the metal shaving before being run through your engine, shouldn't it?

jeep_man_401
02-26-2010, 01:28 PM
Filter could get plugged and bypass all the oil without filtering. Excessively high oil flow/pressure could bypass filter. Cold thick oil bypasses. Was this a new rebuild?

amcjunky
02-26-2010, 05:23 PM
no i bought the motor three years ago....sat for 2yrs and then ran for maybe 20 pass total in the one year. in that one year it went threw 2 sets of dist and cam gears. all other bearing are fine except those 2 i showed you.

so if i check the dizzy to oil pump clearances get the matched set of gears and the new timing cover from here should that fix it?

also dose anyone know if i order the "AMC V8 oil pump kit " do they assemble that before they send it or do i have to assemble it.

thanks for the help justin

ironman_gq
02-27-2010, 03:08 AM
you may have a partially blocked oil galley. AMC motors oil the mains from the lifter galleys and cam. they are backwards of most others the oil flows to the cam first and then down to the crank and rods from the lifter galleys. The first bearings to suffer from oil starvation are the ones at the end of the line the 7 and 8 rod bearings and the last main bearing starve first from lack of pressure or blocked passages. High rpm's regularly will make the problem worse.

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