cam shaft lobe extensively worn

quote:

Originally posted by Uli:
just rebuilt the engine and removed the cam shaft. one cam is complete down. (reason for power lost) what maid be the reason that just one cam is nearly complete down, the other are looking nearly ok ? the block is just in a cleaning / acid process. I like to prevent that happens again. thank you,
Uli

it's a long list of possibilities beginning with a poorly heat treated cam, poorly heat treated lifter, insufficient oil quality, lifter did not rotate in bore, assembly technique ...

which lifter / cam lobe is flat, intake or exhaust on which cylinder?

or which lobe from the front of the cam?

Hi,
the first cam behind the little gear. hope posting the picture will work,reg. Uli

Uli, there's no single reason for flat tappet cam lobe wear, according to professional engine builders. '4V' mentioned a long list of possibilities for failure and I agree. But one thing that is implicated in quite a number of failures is lack of the high-pressure camshaft oil additive Zinc-dithiodiethylphosphate, also known as ZDDP. This additive is vital to today's flat tappet cams & spring pressures and was mostly removed from world oil supplies, due to potential poisoning of catalytic converters- in spite of the vast majority of engines sold today NOT using flat tappets, and the ones that DO need it not using catalytic converters.

Next time, break in a new high quality flat tappet cam and a complete set of new lifters according to the mfgr's strict instructions, using ZDDP as req'd. Then use recommended amounts of the additive for the rest of the engine's life. Think of it as heart medicine for your engine.

Or rebuild your engine with a roller cam. Today's hydraulic rollers are dependable, do not need ZDDP in the oil and do not need periodic lash adjustment, which is difficult at best in a mid-engine Pantera. Sadly, roller cam conversions to a 351-C (which never received them from Ford) are not a bolt-in and are not as cheap as a flat tappet version, but do often produce more power and torque as a bonus.

is the 1st lobe Intake or Exhaust?

could be damage sustained during cam degreeing?

i also forgot to include break-in procedure, Uli how did the cam get broken in?

Insufficient lobe taper is the most likely culprit.

Do you know the name of the cam's manufacturer?

Insufficient lobe taper = lifter did not rotate in it's bore

lifter & pushrod rotation is easily checked by turning the crank by hand and observing each one. mark them if you like, just a Sharpie line anywhere and they'll show evidence of rotation. if they don't, find out why. correcting the situation can be as simple as wiping the lifter bore clean, re-lubing and exercising the lifter up & down in the bore and you'll feel it free up & smooth out

and Yes to what George points out also, cam mfg'rs are skimping a little on lobe taper

synthetic oil is too slippery for flat tappet break-in, the 'tooth' of the lifter foot will not bite the cam lobe and the lifter will fail to rotate

I "suspect" the problem with flat tappet cams flattening lobes, which began occurring approximately 15 years ago, was intentional, perpetrated by a camshaft manufacturer who sells a line of retrofit hydraulic roller cams. This never happens when folks use a custom cam from Bullet Cams. It never happens when Valvoline VR1 is the only lubricant in the sump.

One Warning: Dumping in a can of ZDDP oil additive will reduce the wear protection properties of motor oil, and only make things worse.

Uli I would still like to know the name of the cam manufacturer.

hi all, thanks for the input. I bought the Pantera at Miami Pantera, the maintanance was not as it was told...
I have now all new material from Dennis in Castle Rock, Colerado. new cam shaft, alu heads, etc. for a complete new revise. Crank shaft will be polished if possible. I will check the cam shaft manufacturer name, the cam shaft is in the Garage. keep you poszted, regards
Uli

No help or refund from the seller?

From the guy who sold the car in 2014 to me ? I am a car greenhorn today with some experiences. in 2014, when I bought the car, with no experiences... This forum is very helpful for me.
regards, Uli