[jeff@]

Bare with me, a little back ground. Ever since I bought my 70 with 351c in 2019 I've noticed a little valve train noise, slight ticking. I did research on the Comp XE 274H hydraulic flat tappet cam and pretty much came to the conclusion that it's a noisy cam.

Car has ran more or less flawlessly, last weekend on our way home from a festival Show N Shine the ticking got a little worse, by the time we got home it had escalated to a
cluck cluck cluck noise at lower RPM and idle, like a horse trotting, it got quieter at higher rpm. I am no mechanic by far but I've read a lot hear and on the 351c forum. It was isolated to near the #8 cylinder. This week end I pulled the the valve covers for for the first time for inspection and found that the pedestals are machined with stud mount roller rockers, a pleasant surprise.
I also found the #8 cylinder intake rocker, I believe one closest to the firewall, loose. Loose meaning I could shake it side to side and move the push rod up & down maybe a 1/16", no idea yet where it is on the base circle. Most of the others are snug but a couple are a little loose, I plan to check them all. After watching some videos I also found that several others appear to have the fulcrum's mounted with the flats down, so those will be pulled, inspected and reinstalled.

The rockers are Crane Blue Racer from what I can tell, Blue Racer is etched on them. I pulled the offending rocker and inspected it, the polylock was snug, it had a few more threads showing than the others and the jam bolt was tight, no visible damage and the rollers seem smooth. I pulled the push rod and the ends look pristine. I will try to get a bore scope down the push rod hole to look at the lifter, hoping its not a collapsed lifter or worse!

•Are these quality rockers?
•I have been looking for the chart that shows how to adjust these, if "X" cylinder is up adjust these rockers?
•Is there any reason those fulcrums would be mounded wrong, intentionally?
•I've read they can be adjusted cold and some say it must be warm? Its a booger getting the covers off & on.
•How do you measure push rods, is it over all length end to end?

Thanks
Jeff

 

[jeff@]

The locking set screws look like they are too far down inside the nuts. Like maybe the nut is only engaging a couple of threads on the stud. I have aluminum roller rockers on my Aussie 2V Cleveland heads and the locking set screws are basicall flush with the top of the nut. Maybe your studs are too short. They come in various lengths above the hex.

I'll definitely have to investigate this further. Thanks for the observation!

 

[jeff@]

Hopefully there's no problem with the lifters and it just needs the pre-load adjusted. AWHTX made a good observations regarding the depth of the locking screws. Also noticed two diffferent types of lock nuts???

Yea, I'm going to check the thread engagement on the studs tonight.
No sure what the deal is with the different polylocks either.
Plan is to go over everything while I'm there.

 

[jeff@]

I screwed the polylock down finger tight and ran the set screw down by hand, pulled the polylock and measured from the bottom. Stud thread engagement is .408", is this close enough to 7/16?
Stud length from top of hex to top of threads is 1.75", should I change them to the 1.90"?

 

[jeff@]

Just noticed what looks like rust or some other discoloration on the #1 cylinder pushrod?

View attachment 919124

Had not notice that, I will investigate tomorrow, thanks. I'll try to put a borescope down there too.

 

[jeff@]

I was planning to pull all of them one by one after seen the couple fulcrums installed wrong so I will definitely be pulling the one with rust for inspection.
When I removed that valve cover, the cover bolt that went in the hole just above to the left had some rust on the shaft. I didn't think much of it, just assumed some some moisture had gotten in there at some point but now I will investigate further. Good thing is I don't see any rust anywhere else except that bolt hole.
I suppose while i am in this far i will order the 1.90 rocker studs and swap those out too. The proverbial rabbit hole!

 

[jeff@]

Why rust on just that one spot? And that cover bolt. It doesn’t go into a water passage as far as I know and that pushrod shouldn’t have rust. A good inspection for sure.

Ok good news, the rust from that valve cover bolt got on the push rod when I lifted the cover, it wiped right off. There was also a little rust in the oil on the head that I was able to wipe up, no catastrophe, yet.
Also the push rod looks straight, pic was an optical illusion.
Rabbit hole continues.

 

[jeff@]

Just noticed what looks like rust or some other discoloration on the #1 cylinder pushrod?

View attachment 919124

Yea, it cleaned right up, but good eye!

 

[jeff@]

Is that a mix of 12 point and 6 point nuts? Also, the depth of the allen set screws looks to be all over the place. A bit of a mess, but since it has been running fine for several years, hopefully it can all be corrected. I would also check if the push rod length is correct. I doubt if the person who originally assembled this checked very carefully or had a clue what to look for.....

I thought that "Blue Racer" was used by Wolverine, but some googling revealed that it can be both Crane and Wolverine:


Here are a couple of facts about your Wolverine cam:

First, Wolverine never had their own cam grinding equipment. Their cams were ground by Camshaft Machine Company (CMC) in Jackson, Michigan. Wolverine just provided the packaging, labeling, and the "Blue Racer" name. CMC is one of the 3 major cam companies that actually produce camshafts, and they provide cams for cam "manufacturers" such as Lunati and Crane.

Starting around the 1990's there was a lot of shakeup in the camshaft manufacturing industry with buyouts and sell-offs. CMC actually purchased Wolverine, and not long afterwards, Crane bought CMC, including the Wolverine product line. A few years later, Crane sold CMC to Federal Mogul, but they kept the Wolverine product line. Since Wolverine, as noted, does not have their own cam grinding equipment, Crane grinds many of their cams, and CMC is also still grinding for them. An interesting intertwining note is that Crane has the contract to grind the Summit brand cams, and those cams can be ground by either Crane or CMC, thus effectively making the Summit cams a parallel cam to the Wolverine... Certain cam grinds can be purchased under the Crane, Wolverine, or Summit brand names, and are exactly the same cam, which may have been produced either by Crane or CMC.

So if you measure your lobes as George outlined above and flip open your Crane Cams Catalog you can likely positively identify your cam.

Yea, I am replacing all the polylocks. I checked all the push rods, they seem fine.
The cam and lifter are actually a Comp Cam set, XE 274H cam.