Cam woes. (Mid-Week light reading)

[PbFut]

I will be the first to admit that I know just enough on this subject to be extremely dangerous to my wallet. I tend to be one of those guys that can’t leave well enough alone. The old saying of “since I’m all ready this far”…. You get the idea. So beginning this past June, I pulled out the AC “engine bay components to convert and refresh. It was full of rodent nest and you name it in the ducts. So I cleaned it all up and got the blower and vent flappers all working nicely. Start on the engine bay AC components and what do you know. One thing leads to another and the whole damn front end ends up disassembled, fire wall forward with only frame rails left. Lots of time spent cleaning and painting. New suspension except springs. It all looks really nice now. With the engine out, why not inspect the internals given I have no idea of history. Cylinder walls were in remarkably good shape with well defined honing still very visible.. No bottom end noise prior to disassembly and I really didn’t want to pull the caps for a plastiguage test. Not the best power overall. So what the heck, lets put a reasonable upper end on it, leave the bottom well enough alone, and see what happens. Modest Edelbrock heads and intake were acquired. Already had a nice Edelbrock AVS2 carb that I really like and a HEI setup. Given I was this far with the upper end, why not drop a cam in to give it a little lope just for some attention in the parking lot. Well, that’s when the engine gods woke up and said lets screw with Dan. Being keenly aware of the very common error of over camming low compression engines, I proceeded to do exactly that. The lope sounded like a 1960s pro gasser but every other feature was not to my liking. No big deal. In the total scheme of things a bump stick is pretty cheap and being retired, time is cheap. At least the break in was accomplished with no issues giving me confidence I could still assemble an engine without damage at startup. I was successful once, I can duplicate, right? Back to Comp Cams I go for a little better choice on the grind. I also got some input on this board a while back on cam selection. New cam arrives and I pull things apart and re-install. Initial startup was even quicker this time as I had good setting marks work from. Run-in seemed to go well. Idle was less lopey but still noticeable. Throttle was snappy. I’m thinking I like this. After a successful run-in, I finish up the remaining items like exhaust and such. After a couple days, lets run it up and down the road and see how it feels. Humm…is that lifter tick I hear? Humm, seems the power is less than before. Maybe I didn’t adjust the rockers correctly. Please don’t let this be a cam run-in fail. Yup the engine God’s were apparently not happy with all my unnecessary fiddling and came down hard on me. So maybe the flat tappet route was not the best plan. I am just too willing to over test my shade tree mechanical abilities.
I’ve heard golf is a frustrating hobby sport. Whomever said that never tried motor sports.
Maybe I’ll try a roller.
All in good fun, at my expense. Happy hour here on the west coast is starting early today.
Thanks for reading and letting me release a bit of self-inflicted frustration.

[twoskies]

i feel your pain,
about 5 months ago , my buddy got his shop, first was rebuilding my engine
it ran very well, ok power, but leaked and smoked
started with sealed power flat tappet cam, made it about 100 miles, wore 2 lobes and half of a 3rd, ok
sent motor back to shop to recheck everything, lucky all is good
ordered a Howards flat tappet cam and lifters combo, got about 6 minutes into breakin, tick, shut down, collapsed lifter,
No more flat tappet cams for me
got a Howards Roller cam and lifters
over 600 miles on it and aside from having to change rocker nuts
no complaints

id go with a roller, but either way good luck with your build

[geezer#99]

Interesting stories!
Curious about something though!
Did you hot tank the block to clean it completely or is there another way to clean it?

[tinman_local2]

What motor oil are you using? Any break-in oil or zinc additive? Today's oil doesn't have the minerals for flat tappet cams. I use rotella 10w30. It still has zinc and, I believe, phosphorus. Without those, you can wipe a cam pretty quick.

[Wikid61]

2nd the oil additives. ROTELLA. ZINC. LUCAS. Take the time to research them & the cam/lifter manufactures for the best ($$$) longest lasting products.

[Sheepdip]

Lucas Zinc Additive every oil change without fail or the flat tappet will fail.

[72SB]

OP

well me and other replies have the same ?.....did you use "break in" aka high zinc oil for your cam run in?

Joe Gibbs, Valvoline VR1 have high zinc

and also did you put new lifters in?

IMHO any new cam be it flat tappet or full roller...wants new lifters

[PbFut]

Yes, aware of the issues with todays oils. This blog is a interesting read. https://540ratblog.wordpress.com/ I did not swap out new lifters for the second cam given they only had 30 or 40 minutes on them and had zero appearance of wear. I think the real issue was that it took me a couple days to complete the second install and much of the assembly oil likely dropped off. Pressure is good and came up very quick at start so I think it was just my slow pace that caused the problem.
I looked at Comp Cams site yesterday. Appears they may be out of stock on the retro roller lifters. Any suggestions for alternatives? I've never retro fitted a roller into a 1st Gen SBC. Do all the roller cams need a button? And does the cover need to be specific to retain the button in place?

[MARKDTN]

Old lifters with new cam? I would not have done that. Even with less than an hour that was a big risk. I'd also put new lifters this time.

There is going to be metal in the bottom end now. Since you are not deep into the short block, you might consider finding a later TBI or Vortec 350 that already has a roller cam and put your heads on it. Just a thought.

[72SB]

Howards have good reviews, especially over Comp. Might want to consider a retro set and cam from them

[LNP]

Did you use the break in lube for the camshaft? And follow the breakin procedure once the engine is fired up? As mentioned you wanna add zinc to your oil or buy some with oil. Breakin engine oil is always a different weight than the oil you run normally.

[RustyBucket]

Out of curiosity what did the wiped out lobes look like. I wonder how much material was released inside the engine, how it's sized & shaped & where it is now. I'd guess it would return to the pan and maybe get stuck to the magnet on the drain plug... OR, depending how it was shaped, go through the oil pump screen and into the oil pump. I wonder if the cam/lifter debris would go through the pump gears and back into the lubrication system. What then? Score up a crank bearing, get stuck in a lifter. Interesting wonder with plenty of possibilities.
A long time ago I had a spring clip come out of the top of a lifter and a piece of it jammed between the gears in the oil pump. It stopped the pump by shearing the drive where the shaft couples together. Luckily, I heard all the lifters clattering from no oil pressure & shut it off.

[72SB]

my experience with wiped cam lobe is metal did go through the system and scored main & rod bearings

[MJN]

Just my $.02 but its possible the lack of assembly lube caused the cam to wipe out but may not have been entirely the cause. The last one I rebuilt I installed the cam close to a year before the first fire and have had no issues. I would suggest using something a bit heavier than oil like Isky Rev Lube if you're waiting a while after installing the cam so it isn't dry at first start up.
https://iskycams.com/shop/index.php?...ndex&cPath=153

Also, I used AMSOIL Break-in https://www.amsoil.com/p/break-in-oil-sae-30-brk/ and continue to run AMSOIL Z-Rod in my 350, both contain plenty of zinc for flat tappet cam and lifters and I have not had a single issue but use whatever you're comfortable with. Follow the cam manufacturers break-in guidelines as well to properly break-in the cam.
Again, just my $.02.

[MARKDTN]

So what happened?

[BAD1916]

My boss has a 66 Shelby with the numbers matching hipo 289. It had to be rebuilt and the comp cams camshaft went flat real quick. Did all the break in oil and all that. I found a company that offers a cam break in service but I believe it is only for Fords. I don’t know if there is anyone doing this for our trucks or not. Here’s a link to their webpage with videos and info on what they do.
http://www.camresearchcorp.com/camking/

[PbFut]

A follow up to the story. The cam was mangled pretty good. It was going south in a hurry. There were 3 for sure on their way out as 3 lifters had to be dropped out the bottom. I used plenty of comp cam assembly oil/lube but it still failed. My mistake was using the 20 minute old lifters from the original install of the Comp Cam that was too aggressive for the bottom end compression. I phone ordered the second cam from Comp. Salesman asked if I wanted lifters. Mistakenly I said no as mine were only 20 minutes old. The salesman at that point should have stopped me and told me what a dumb move that was. So for the third Cam, I went to Howards and ponied up for a retro roller attempting to avoind the flat tappet break in issue. So far so good. About 3 hours on the motor with the new cam. No issues at this time. Quiet, smooth, ok power, plenty oil pressure. The bottom end has unknown miles so I was not keenly concerned about damage from the cam dust. I know many of you will cringe at that move. As I disassembled I paid close attention to the appearance of the oil. Everything in the stream after the filter was exceptionally clean vs. the gray stuff in the pan. My thought, right or wrong, is that the oil under pressure to the crank was clean enough via the wix filter not to have damaged anything to the point of excessive on the unknown mile bottom end. I drained the oil and ran three washes of diesel fuel through the oil system using a pump primer and changing the filter each time. The final cycle came out looking as clean as it went in Honestly the first cycle was not too bad looking I then cycled a jug of break in oil to push out the fuel in the gallies. Drained the flush oil. Removed the old cam and lifters. Push rods were already out before the cleaning. Bearings looked the same as when it all started. This was not a rebuild. Just cam and head swap so there is unknown miles on cam bearings and bottom end. Also why I did not feel a need to fully disassemble after cam failure. 3 lifters were mushroomed and had to drop out the bottom. The new Roller cam required me to set up a button. I used the clay method. I had some clay bar sitting around. Worked very well. It is sticky enough to hold the button when you remove the cover. Milling a little at a time until I had .007 gap between the timing cover fully torqued and the button. Measured with the clay holding the button off the cover removed with a feeler. There is 3 hours on the 3rd cam at this point. The run in oil change was completed and is pristine in appearance. I am hopeful this shade tree procedure will work out in my favor. The truck is not driven that much. Just around town. If I get 10K out of this procedure it will be 2 or 3 years.

[geezer#99]

Did you need to use a melonized distributor gear with the Howard’s roller?

[Grumpy old man]

As long as your convinced it's OK thats all that matters .

[jaros44sr]

Originally Posted by geezer#99

Did you need to use a melonized distributor gear with the Howard’s roller?

Good point.........curious

[geezer#99]

And, did you crank up the rpm for 10 or more minutes to adequately oil the new cam and lifters?

[Accelo]

Just another reason to like the later SBC and the LS motors. Roller cams from the factory. I have just heard about so many flat cams lately.

A couple ideas that help besides the ones mentioned like oil additives.
Motors tend to overheat on the initial start. This cuts int the cam break-in time.
Leave the highest heater hose off when filling the motor. When you get liquid leaking from this hose reattach it. The assures the block is full.
Have the largest 110V fan you can find blowing on the radiator.
Start the motor during the coolest part of the day.

If you are using a modern FI or an aftermarket system like the Holley that requires a O2 sensor be sure to use mufflers or a long extension on the exhaust. Open headers makes for a disaster of the Air Fuel mixtures when the 02 sensor isn't protected from ambient air. It goes farther up the exhaust, with reversion, than one would believe possible. It will mess with the air fuel and make a mess of the initial learn.

It's the splash from the crank that lubes the camshaft, so the rpm is needed.