Camshaft failure

[Ben Kallies]

This whole cam failure has me thinking. My motor has always had a lot of oil pressure - like 80 psi cold, and never less than 60 psi. I'm running a Mehling high volume pump, because it was what I had. Even with this pump, is this unusually high? Could this be a sign of blockage somewhere? I'd love to hear your thoughts. A new oil pump will definitely be in the works. Thanks.

-Ben

[Bob Pagano]

Better question, what oil did you break it in with, I hope not the synthetic.

[Ben Kallies]

Bob,

I broke it in with non-synthetic 10W30 if I recall.

[Bob Pagano]

Ben, Look back and see if it had zinc in it, your problem may have started there. We break in all motors started at the shop with 30 or 40 wt oil, no multi wt oils or Syn ever, not till engine is run in.

[njk53]

My street hot rod has a high volume pump and has 60 PSI of oil pressure all of the time with no problems. I think if the engine was broken in with a conventional motor oil, that was the start of the problem as Bob Pagano suggested. Conventional motor oils have little or no zinc in them.

[Adger Smith]

Ben,
To add to the problem of no Zinc as Bob said was the multi Viscosity oil. 10W-30 is not 30 weight oil & doesn't have the same shear or EP rating as a single weight oil. When I put an engine on the dyno it has a heavy single weight oil in it. Or it has VP break in oil in the engines with real lite ring packages. I never use a synthetic for inital start up or break in. These older engines we are racing with had oil systems that were designed before the thin oils became the vogue. Unless you build the clearances correct for thin oil (read that Multiple viscosity oil, too)I feel you are just asking for trouble using it. The way a cam gets oil is by what is tossed or spun off the crank, Rod side clearance helps. Then we put better pans & scrapers that remove this rope of oil from the crank, to cause more lifter/cam oiling problems. The other way a cam is oiled is small amounts of oil that sheds from around the lifter and drips on the cam. We reduce this by having tight lifter bores & some people still think they need oil restricters in the lifter passages. I've seen a flat cam In almost every case that I've seen backyard or Magazine engine builders block the oil drain holes in the lifter valley. I've also seen it in late model engines that are designed for roller cams and a flat lifter cam is used. Most of those blocks don't have drainback holes along the cam in the valley. What does blocking those hole really do. I think it air locks the upper part of the cam tunnel. How can oil get thrown from the crank into that area on top of the cam where the lifters ride when it is in an air lock? Common sense and careful preparation along with the right lubricants keep cams from going flat. I stay away from the tricks of the week that makes 2 more HP & cuts engine life by 50%. One more thing I preach to customers is IDLE TIME & SPEED. Low idle times & high Idle speeds keep cams & lifters oiled. (doesn't do anything for the cool sound, though) I would venture to say that in the 5 years Bob was hanging around the shop he didn't see one flat cam. If he did I can't remember. Right Bob? Did I miss anything?

[CrateCamaro]

Ive been running Valvoline 20W50 "Not for Street Use" with a bottle of AC Delco Engine Oil Supplement right from the GM dealer with no trouble as of yet. I have also run 10W30 Not For Street Use but it makes my oil pressure light flicker when its hot. I was told that this oil still has zinc in it and is specialy made for flat tappet camshafts. And I broke it in on Rotella T 10W40 as per Comp Cams. And I always thought Rotella T was for the lawnmower and rototiller. Hope this helps.

[Ben Kallies]

Thank you again to all that replied. I appreciate you taking the time to share your experience. Adger, Your in-depth thoughts on oil control is great. Bob's always spoken highly of your qualifications as an engine builder. Thanks again.

-Ben

[Bob Pagano]

Rotella Was a good choice, all their oils now have little or no zinc, unless you have old stock you better check the labels. Adger is right, no cams lost in the five years I have been there.

[CrateCamaro]

Yes you are right. They are removing the zinc from Rotella as well. They are going to be removing the Comp Cams additive off the shelves as well due to curren government regulations. I recently freshened a motor for a guy in a corvette. He wanted to tame it up a bit so we pulled out the solid roller that was in the engine and stabbed a "tried, tested and true" 292 Comp Cam. I followed all the instructions for the break in....Rotella T, Comp Cams cam lube, bottle of comp cams break in additive, break in springs...ect. The break in couldn't have been better...started on lest than half a revolution, no heat, ran smooth at 3000 rpm for 30 minutes. I was so confident that we passed the break in I washed and waxed the guys car for him so he could drive it home and be proud. Half way home a lobe gave up. I called comp to see what I did wrong and all I got was, "hahah ya it happens and expect more of it". This came right from cam company!! They couldnt come good for the warrenty but sent me a hydralic roller setup for a crazy price that the owner couldn't say no to and hes driving it as we speak.

PS...Before this I was using ARP lube on all the flat tappet camshafts for break-in and this was the first time for the comp cams lube and it didn't go too well. I figured I would follow all there recomendations that way if there was any failure I would have an argument. Went back to the ARP for my new stocker cam and it seems to be mint. Food for thought....