Cam Failure

[John]

FrankZ, if it is reasonable to do, I would like to see a picture of the bottoms of all the lifters in that set that was clear, front to rear. 1-12 whatever works
John

[FrankZ]

Send me you Email address via PM and I can send you a hi-rez copy of the third pic in my post above. The lifters (2-11) are shown in order from front to back.

[Muad'Dib]

Send me you Email address via PM and I can send you a hi-rez copy of the third pic in my post above. The lifters (2-11) are shown in order from front to back.

Dont forget you can email people from this webpage by clicking the email icon below thier name in each post. This icon is only available if the person allows to be emailed through the board. In John's case .. you can email him.

[FrankZ]

can't attach pics through that link.

[Muad'Dib]

can't attach pics through that link.

Sometimes i get ahead of myself

I guess i was just assuming you would link to a full size picture.

[oletshot]

I'm not getting it. How does more flow cause less oiling?
I've heard of people thinking they pumped all the oil into the top half of the engine, is this what your thinking happened to yours.

[John]

Send me you Email address via PM and I can send you a hi-rez copy of the third pic in my post above. The lifters (2-11) are shown in order from front to back.

On it's way. Thanks
John

[1bolt]

All the cam failures are one lobe and lifter ate up. pretty much anyway, I think I saw a thread on one cam where there was abnormal wear on two lobes...

I don't think it's the Oil pump either.

It's hard to point at ZDDP due to Rotella but recent formulations of Rottella T have less zinc.

My Hesco RVOB cam didn't last 500 miles... One lobe and one badly dished Crane lifter... Stock oil pump, but this was a few years back when I knew next to nothing about the ZDDP issue and sure enough I had lower ZDDP oil (probably a 800-900 zinc and phos formulation about three years back) and no break in additive.

I still think there's a combination of poorly heat treated or nitrided crane lifters and poor ZDDP.

I bet a lot of Cams that aren't Crane's were installed along with a set of fresh Crane Lifters...

[Flash]

All the cam failures are one lobe and lifter ate up. pretty much anyway, I think I saw a thread on one cam where there was abnormal wear on two lobes...

I don't think it's the Oil pump either.

It's hard to point at ZDDP due to Rotella but recent formulations of Rottella T have less zinc.

My Hesco RVOB cam didn't last 500 miles... One lobe and one badly dished Crane lifter... Stock oil pump, but this was a few years back when I knew next to nothing about the ZDDP issue and sure enough I had lower ZDDP oil (probably a 800-900 zinc and phos formulation about three years back) and no break in additive.

I still think there's a combination of poorly heat treated or nitrided crane lifters and poor ZDDP.

I bet a lot of Cams that aren't Crane's were installed along with a set of fresh Crane Lifters...

I agree!

I also thing the cam width has a lot to do with it.............Does any body, after market, sell a cam with the stock with lobe?????

I just got this so for those that have been saying it all along, Sorry BUT

The width will make a grade difference on how much load is put on the cam suffice
EXAMPLE: If the lifter was actually 1 inch in diameter and the cam lobe the same,.... and the seat, spring pressure was 100 pounds(one hundred pound per Square inch) the spring pressure would 100 psi.

Now if the above was the same but the cam lobe was .500 or half inch(1/2") the Pound per square inch would be double (200 psi of pressure) to raise the valve off of its seat.
I just used these numbers because they are simple numbers.....but you get what what I'm trying to say

We first raise the pressure on the cam by using an aftermarket cam(smaller width lobes)........then, (because its a bigger cam) we add more spring pressure to the valve.......adding even more pressure to the cam shaft.

I thing the aftermarket cams need more zinc then what was in the bottle of oil before............they changed the recipe on us!!!

Has any one found out if the MPP cams use the stock with lobes?

Flash

[John]

Got the photos, thanks, let me study those for a little bit before I make room for my other foot. What does the distributor gear look like?
John

[gradon]

Hey flash(and others), the mopar cams do have the same wide lobes as the factory cams(at least my 30 does). I measured a lobe to be ~5/8". I don't know if the narrower lobes are part of the problem, but it's a factor I don't have to worry about.

[oletshot]

The wider lobe was one of the reasons I was choosing the 29 Mopar cam, and lift wasn't to radical as I wan't to run stock springs. Unfortunately, I was told they weren't available at this time, part # was still a valid #, just no one has them.
One thing to remember is oil with low ZDDP will not single out one lobe to attack, I feel you would see affects on all lobes.
I wasn't necessarily saying I didn't think oil pump, I just couldn't come up with a way that more oil = less lubrication. FrankZ seemed to be sure of his theory, I would like to hear his reasoning so I could understand.

[FrankZ]

John,
Thanks for taking the time to eyeball the pics and the distributor gear looks good, i did install a new cam bolt, spring, and pin when I built the motor last year.

FWIW,
I ordered the following today;
Crower Baja Beast Cam
Crower Cam Saver Lifters
New Rod and Main bearings
New Gasket Set
New Melling Standard Volume Oil Pump
New True Roller Timing Set

I'll order new pushrods after I get the motor back together enough to measure the lifter pre-load.

[John]

The distributor gear on the camshaft looked good also, so I don't think your cam was walking. Any wear marks on the plug behind the cam at the rear. Oil pressure history? I do see wear elsewhere. Again let me think about what I am seeing. Hate to see your bad cam, we have to see what factors we need to/can control to reduce these failures.
John

[FrankZ]

Nothing unusual on the plug, no unusual oil pressure issues either.