427Hotrod

Last weekend I started getting the '67 with the 540 ready to make the drive from Houston to Bowling Green for the Cruise In.

So I pulled intake to perform the annual "roller lifter" inspection. Last year I installed some with pressurized oil to axles and I'm glad to report they were all perfect. Cam also looked new...so that was all good! I've been happy all year that with all the racing and cruising I've been doing the adjustment has never needed anything. I've checked them a couple of times and it was dead on each time.

So I had to decide...install my new set of "backup" lifters or stick the flat tappet cam in it for the trip. The backup lifters don't have the pressurized oiling and whether they would live for the long trip is questionable. I got by last year, even though I was using a more radical cam...but who know's this time? I run a pretty good bit of spring pressure.

So I wussed out and decided to put the old solid flat tappet Crane from off the shelf back in it. You may remember, I tried it last summer for awhile just for grins and even though it gave up a good bit of power, it actually ran better than I expected.

So I replaced the cam and was in the middle of changing the springs to the flat tappet type, when along about the 10th valve, I found that one of the valve keepers was broken in two! Uh oh.......well..hopefully a freak deal right?

Well about two more valves later, I found another broken one!!!

That does it...time to change ALL of them!

So the bad news is I'll be slightly down on power running the flat tappet. The good news is there is NO WAY I would have known the keepers were broken if I hadn't been changing springs! If I had just stuck the other lifters in it, I could easily have been stranded somewhere in the middle of Arkansas with a dropped valve!!

Interestingly, these keepers are 10* machined Comp ones with lash cap recess and identical to the ones Vettemaniac found were broken on his heads last year! I sent them in to Comp along with the lifters to be rebuilt to see what they say.

But I ordered new K-Motion retainers this time!!


Moral- check valvetrain stuff often!!



JIM

VETDRMS

Good thing you caught that...

On a similar note, when I took mine out to the track this weekend I noticed it was starting to break up around 7000rpm...felt like valve float so I popped a couple springs and they were a little down on pressure, after 60+ passes and 5000 hard miles its time to replace them. Picked up a new set of springs today, should have them on by noon tomorrow.

Glad to hear you avoided that mess, have a fun & safe trip!
I will be sure to check everything out thoroughly tomorrow!

GrandSportC3

Glad that you found the broken keepers!
Are you going to race during the Cruise In??

427Hotrod

Not sure what we're going to do as far as racing. I'm driving it up, so I won't have much support equipment..like slicks etc.

Probably be fun with a little flat tappet cam and plain 'ole BFG's huh?

Could see who could spin the longest!!

Maybe next year I'll bring it on a trailer loaded for bear! Uh oh...did I just say trailer??? Oh No!!

JIM

GrandSportC3

Just get a set of Drag Radials.. The ET Strees Drag Radials stick like slicks and are great on the street!

Grinchia

I had a broken keeper last spring, but the first symptom was a sudden loud ticking from the passenger side cylinder head as I was driving along . Called a buddy for a quick tow home, and diagnostic disassenbly revealed a dropped exhaust valve on #8. Fortunately (INCREDIBLY!), even though the valve was bent nearly in half, it jammed up into the combustion chamber and stayed there. No cylinder wall damage, no piston damage (a tiny scuff), and no head damage (gotta like cast iron!). I should post a pic of that valve, it's still hanging over my workbench...

427Hotrod

Yeah, I could get some drag radials....but 2000 miles up there and back along with a nights racing.....they'd be gone.

Might still find a way to bring slicks...hmmm....gotta think......


Still down on power though.....


C'mon.....let's drive yours up too!! Half the fun is the road trip!!


JIM

pef427

HHHEEEEERRRE we go! This is how it starts...Add a little encouragement CF fans..Jim does the best burn-out I've ever witnessed.

GrandSportC3

I'd have to dial in the car for pump gas to drive up there... I also wouldn't fit my slicks into the car and the ET street tires aren't too save for the street even though they are street legal...

gkull

Jim - were they broken horizontaly or lengthwise with the stem? The reason I ask is many years a go during a tranny failure I severly over revved my motor. I also had some horizontaly broken and cracked Crane hardened 10* keepers The cause was the valve stems in the grooves had mushroomed and crushed the keepers in the retainers.

When I talked to Crane cams the person informed me that valve float creates tremendous forces on the valve stem. He also told me that the only other way to break them is if they truely aren't seated in the groves upon installation.

The down side of hardened keepers is that they are hard and brittle. I still use the best today and keep my fingers crossed and my rev limiter on!

I wish that i had the power to decide that I have to much and want to tone it down :o

427Hotrod

George...

They were broken vertically. Instead of pulling out "2" valve keepers, I had "3" or "4" of them on each valve!

At first I thought maybe lash caps were the issue. I know I checked to make sure they were OK as far as depth goes so that they wouldn't hit keeper. They are fine.

You're right..they are awful hard and brittle.


You wouldn't think I "might" have twisted it a little tight a time or two would you??


JIM