parchisi

Here's my camshaft with about 30,000 miles on it, Engnbldr 261C. I can't tell if that pitting is just what the metal surface is like or if that's galling and the cam needs replacement. Thank you in advance for your advice!

millball

The cam is ruined, the surfaces should be smooth as glass. How many lobes look like that???

Did you start with new rocker arms?? What oil are you using?? Did you use any ZDDP additive in the first break in oil???

parchisi

That's what I was afraid of. Some lobes are worse than others, the worst one is the top picture. Rockers arms were new from 22reperformance. Used Clevite assembly lube conventional valvoline oil. I guess this time around I'll use the assembly lube along with some Joe Gibbs break in oil.

scope103

I don't think a cam should be as smooth as GLASS, but it is a ground surface, and it will get a little smoother yet with wear.

And those cams are pretty badly damaged. I'm not expert enough to tell from a photo, but those sure look like oil starvation over thousands of miles. Assembly lube wouldn't hurt, but I don't think that was the problem. Any chance you have a blocked oil passage?

Co_94_PU

iTrader: (-1)

Not enough pictures.. But it looks like this has all the damage on the intake side lobes.

parchisi

The lobes i took pictures of represent the worst of them. Two of them have no damage and the rest have slight damage, both intake and exhaust lobes. Do we think there might be a blockage in the rocker rail? The rock rings never sealed correctly (reason for the rebuild, 30 psi in #1 and 170 psi wet, the rest were right at 120) so I'm guessing the oil may have been getting some fuel mixed in and not lubricating as well as it should have. It would turn black in a matter of a couple hundred miles. One of the rocker arms is scored from the lobe in the first picture, I'm going to replace them all with new ones.

scope103

"Modern" (well, second half of 20th century) oils have detergents, which will scavenge up dirt and make the oil turn black very quickly. Unless you completely rinse out the oil system every time you change the oil, I wouldn't worry much about black oil.

If the oil SMELLED like gasoline when you pulled the dipstick, then I would worry.

skypilot

iTrader: (1)

That cam is junk, drain the coolant out of the block and pull that like a bad tooth. It looks to my as if its a cheap Chinese made soft metal junk. Send that cam out to Delta Cams in Tacoma WA for a trade in on a real Toyota regrind. Also that one lifter / rocker is probably junk just from running over that really bad lobe. So it appears you have some additional issues.

Also modern oils do not properly lubricate flat tappet cams. check out a blog by 540rat on this problem. I use Mobile one in my 22R / RE for this reason, its on the top of his list and I'm not having any issues like you are.

I think LCE has better rocker arm shafts with improved oil distribution.

parchisi

Just ordered a rv2 cam from yotashop.com. Pretty sure it's the same one from johns foreign engines in which case it's an oe regrind. Also just sprung for a set of rockers from lce...not cheap but a few of the rocker pads had scoring so I'm going to go the safe route. The rocker shafts are from Putneys with the improved oiling so I'm just going to reuse those.

another question....i noticed the wear pattern isn't flat across the face of the lobe and tappet, is this normal? It's like the rocker was only making contact on an edge then wore down towards the center.

Thank you everyone for the shared wisdom.

skypilot

iTrader: (1)

Yes that's normal for solid lifter cams, they are pre-loaded backwards to keep from walking around. Did you have a chance to look at 540rat's blog?

parchisi

Yes, I got around to looking at the blog. At first, I was like, what are you, my professor making sure I did my reading assignment? But now I see what you were getting at. I skimmed through a lot but focused on the part about break-in oils. 540rat brings up a lot of good questions, makes me doubt break-in oil is the right answer. I think I might go ahead and sell that Joe Gibbs break-in oil and get a good dino oil that ranks high on the list...the Valvoline VR1 looks like it has very good wear protection, a moderate amount of ZDDP (above 1200 at least), and not a synthetic. Google searching 540ratblog brings up a lot of contrarian opinions as well, so for the uninformed like myself it's hard to determine where the truth lies...maybe somewhere in the middle. Although from what I read, 540rat contends that modern oils should do a fine job of protecting flat tappet cams, the only factor that really matters is film strength. ZDDP is not necessary and if anything, in concentrations too high, will increase wear. Controversial stuff but he makes a convincing argument.