camshaft lobe flat what now??

93dps

i just bought a 79 cj7 with a 304 that had a bad miss.pulled valve cover and intake discovered collapsed lifter on exhaust on #1 cylnder.pulled lifter it is concave , cam lobe looks flat.it is a relativley new motor and i would like to run it for a while if i can.i know there has to be metal from the lifter and lobe in the motor .is there any way to flush the motor without pulling it and completly going through it?i know the best route would be to do that but its just not an option right now.

jeepsr4ever

The small particles will be caught by the filter and I would only change oil and filter and get a new cam and lifter set.

Goose

I second that.. also one step you might take if you can get the pan off in the truck.. pull it and clean it out (or put a magnetic drain bolt in it) but If you cant get the pan off without a bunch of aggravation.. run it.. Like MC says thats what the filter is for..

93dps

i like the sound of that! this is my first AMC v8 and i was reading some of the dist gear oiling post and im gittin skeerd.i have ordered the summit 8600 cam kit and summit roller timing gear set with edl.springs.any advice on what to look out for,or any advice yaull have for doing this job would be appreciated.

93dps

what should i look for on this summit cam?should i rebuild the oil pump while i have it apart?any tip at all? thanks

82Waggy

Well, I hate to say this but I would send that Summit cam back and look for something with less duration. The late intake closing point and big overlap of that cam in a stock compression 304 will kill power across the range. Highly recommend the new Engle 5015-H for this application - should work just fine with your new springs - and will help build torque all around. Yes, rebuild the pump if necessary. Check for scoring around the circumference of the pump housing walls and slop at the gear shafts - if present, get a new cover, gear set, and midplate from Bulltear.

Holeshot

Also, be sure to check the oil pressure hot before going any further. Let us know what it is & if it goes up with the RPMs.

AMX69PHATTY

Be sure to confirm alignment of all the little oil passages that feed the Distributor Gear. Grooved front Cam Bearing Hole through or groove around face and hole in front side of front Cam Journal Notch in back face of Cam Timing Sprocket and chamfer around bore Unobstructed 2nd "keyway" in Cam Sprocket, Pump Eccentric, Distributor Gear Unobstructed holes between Distributor Gear Teeth Cam Snout Bolt Washer is Flat and seals against Distributor Gear counterbore Cam Bolt itself isn't too long and does not bottom out in Cam Snout Tapped Hole Also make sure there are oil relief holes axially through the rear most journal which allow oil to escape from the cavity between the cam butt and freeze plug.

93dps

got her going.went ahead and kept the summit cam.just like everyone here says,the timing gear had to be cleaned up but everything else looked good.i primed the motor before cranking it and had good pressure(50#) on the mechanical gauge.got it fired up pressure ran up to 60# then started dropping to about 10. i shut it down and started to cuss but i remembered reading on this board not use a FRAM FILTER.bought a WIX ,put it on everything is good,15-20 at idle 50 -60 up in the revs. the reason im posting is to THANK YOU guys who contribute to this board =D> ,you saved me a tear down,and more money.the cam sounds good i just need to work on getting everthing dialed in,i have my static timing at 10 right now i think im going to try to bump it up a little to see if i can get more snap.THANKS AGAIN for yaulls input. :t:

fifesjeep

I can't believe I'm hearing this information when there are known Harmful particles or shavings floating around inside the engine... 🙁:

"The small particles will be caught by the filter and I would only change oil and filter and get a new cam and lifter set".

"I second that.. also one step you might take if you can get the pan off in the truck.. pull it and clean it out (or put a magnetic drain bolt in it) but If you cant get the pan off without a bunch of aggravation.. run it.. Like MC says thats what the filter is for"..

(I don't mean no disrespect to anybody, I just disagree with what has been said).

1st: The oil filter is rated for only so much "filtering"... and with that being said the oil filter has a certain micron level that the filter will constantly filter which it is designed to catch and let the "good/decent" fluid go past... With all of these metal particles in the oil/engine the filter isn't going to work properly which will cause more fluids with the metal particles to pass by or go around.. It doesn't take much for an oil filter to clog and with an old/used oil pump... (Pressure relief valve assembly and bypass assembly) I'll be willing to bet that his engine won't see the full life that it should due to these particles running around inside... Maybe it's a good thing he didn't drop a lot of coin into this thing! But any foreign materials in the oil should always be adressed properly in-order for things to work properly for the present and the future.. This is engine is going to see premature wearing of internal parts due to these metal particles.

The Summit 8600 cam.. Is sort of pushing the limits of that stock 304.. (For getting the most performance out of it before you start losing it)..you probably would've had better results with something around a .456 gross valve lift... But then again "To one his own".. You never know though, Everybody told me that my 360 was going to be a pinger... And I'm running a little over 9:1 compression and I can run her off of Premium pump gas with no pinging... (I will say she runs strong on 103+ Octane :mrgreen: )

jeepsr4ever

When we are talking about a cam lobe going flat their is no amount of cleaning that will get rid of the microscopic particles better than a oil filter. Remember this is a not distributor gear or other large metal chips. When a cam lobe goes flat the metal softens and desinegrates...doesnt chip. Hope that helps

Goose

More importantly.. that Cam lobe didnt go flat yesterday.. It has been grinding away for a looong time..so what damage there is ..is done long ago. probably 6 or 7 oil changes since it started. Coming from the Small block chevy world.. Flat cam lobes are almost as common as changing spark plugs.. the sludge in the pan can trap some of the heavier particles. which is why I suggested that.

fifesjeep

No-way man... I would've torn the engine apart and had it flushed and then a dip in the tank... (but that's me). He said "it is a relativley new motor and i would like to run it for a while if i can".... That's not sitting with me too well!!!
I broke in a cam in one of my old 304's and ground either #1 exhaust or #3 intake lobe flat and dished the lifter deep enough to puncture a hole in it... And that didn't take no time... Maybe 4 to 6 hours of totally run time and she was cooked... I drained the oil and sure enough it came out blackish-brown with particles... the oil felt gritty... Once a cam lobe or lifter starts going it goes quickly... (Depending on how it is driven. But, needless, it goes quickly once the hardened case is gone... especially at what speeds the cam runs at). Now, if it (flat lobe/Dished Lifter) happened over a period of time and it didn't get driven much and the oil was changed before the 2000-3000 mark then I can sort of see your point... (depending on how much one trusts his filters/engine/luck).
But, maybe it's me.. maybe it's just good practice but... Anytime you have harmful foreign particles in the oil it's a bad thing and I wouldn't trust any oil filter to protect my investment knowing that there are harmful particles floating around... And seeing that they're like metals and there's a lot friction happening they're going to get magnetized and they'll ended-up in every nook-&-cranny... And those particles will gather in a location until they can't stick no-more due to the mass of particles and flow of oil and when these little particles (which gathered to become one big particle) move and get stuck in a lifter or pushrod or oiling hole there's going to be bigger problems... But, to one his own... I highly doubt that his filter filtered all of the metal particles... It's Common sense really... What percentage of oil actually gets purified as the car is running at Highway speeds?... You or somebody should call the manufacturers and see what they say... (If they'll even say). I've tried but to no avail they keep giving me different numbers to call or they'll give me an address to write/email... Fram is real good at avoiding this question..

76-cj7

I think i'll agree with MC on this one considering i purchased a 76 CJ-7 with a 304 and Summit cam. The dumbass before me destroyed 3 of the Summit cams in the same motor before deciding to sell the jeep because he was too stupid to figure it out, he also put .040 bearings in the bottom end when it was a stock sized crank too :(: You can imagine my aggravation when this was found out. I dont know what he was doing when he decided to "rebuild" the motor as he put it. He even went as far as Harland-Sharpe roller rockers that didnt help along with grinding the tops of the valves even to the keepers to try and fix the valvetrain problem.

93dps

like i said in my first post,iknow tearing it down all the way and cleaning it would have been the best way to go,but so would have been replacing it with a 360.like i also said that isnt an option right now.i spent about 200 bucks and a few days under the hood and lurking in here and im driving it now.if it grenades tommorow im just out a couple hundred bucks and some time.then ill try to find a 360 or put a small block chevy in it.im just saying there is a lot of good info on this board and not a whole lot of BS like on some of the other boards.