I'm putting together my heads today, and I'm installing the new titanium retainers and 10* locks. Well, I get one of the spring/retainer installed, then I whack it w/a rubber mallet. Then, one of the D*MN locks breaks in half and the spring cocks sideways about to come out!!!! These are Comp retainers and locks. Now I'm freaked out and not sure if I want to run this setup.

I don't know if whacking it w/mallet was a good idea, but I read in more than one place thats what builders like to do. Upon closer inspection, I saw that the retainer sits slightly higher than the valve tip (+.050 retainers). I think the mallet drove the retainer down off the locks then it slamed back-up. Hope I didn't mess up all the locks.

I've never heard of the mallet bit before.
I would compress and remove that spring and check the retainer for damage.
When I assemble heads, I just use a small dab of grease to "glue" the lock
on the valvestem and gently release the spring compressor until the retainer seats nicely against the locks, no hammers required.
Can't speak for why the lock might have broke.

Just a "tap" w/the mallet...no running start or anything like that. Good thing I did though!

The lock should have never broken regardless. I take my heads apart that way, I smack the retainer to break the seat against the locks . That way the spring compressor doesn't have to do it. One thing is though you might want to look into valve locks with the lash cap recess. This way you can get lash caps and get the tip height above the retainer again.

I'always tap the top of the valve after installing locks to make sure there seated . ive never had a problem with doing this. better it came off now than after it was fired up,thats the whole purpose of of tapping it. dont know why it would have broke though.

Don't know why it broke either. It kinda looks like its a cast part :confused: . I'm changing all of them - maybe I have a bad batch.

Vince,
I have seen them broken quite a few times. I dont think they like being installed at all crooked, or not seated properly. I have broken them myself during assembly. I just took a set of Brodix heads apart last week that had three broken locks. I don't know what brand they were.

Vince,
I have seen them broken quite a few times. I dont think they like being installed at all crooked, or not seated properly. I have broken them myself during assembly. I just took a set of Brodix heads apart last week that had three broken locks. I don't know what brand they were.

I may of been too rough installing them but geesh...you would think they could tolerate it. Thats why I'm replacing all of them. I'll bet the stamped OE's wouldn't of broke.

Seen it numerous time also. We took a buddys heads apart last year and found a few broken.

I also found several broken on mine last year. It's a scary feeling!

One think I can tell you is that if during assy you ever allow one to fall out and get cocked, you can almost count on it to get cracked.

Replace them all just to be sure and be very careful as you release springs.

JIM

This is crazy...these things are marketed as being much stronger than stock. Maybe these are made in China.

Hi Vince,
They'll last for years under normal circumstances but they WILL break if they're not installed carefully. The retainer and springs have enough pressure to cause this to happen. It becomes especially important to be very careful when working with "hi-pressure" roller springs. Catch the lock at the wrong angle and it'll snap. Thanks, Gary in N.Y.
P.S. If you find broken locks on a running unit, you will most likely find one of two things, either spring pressure is too low or rockers are contacting retainers.

Gary, is this a Comp Cams thing or does this hold true for all aftermarket locks?

Gary, is this a Comp Cams thing or does this hold true for all aftermarket locks?

Hi Vince, we've seen it on all brands. We do use mostly Comps now but we have Crane, Lunati, Crower, and most others "on-the-shelf". We keep the Cranes mostly for 7 degree (machined) units that we build. Believe me they will all break under the "right" conditions. Under "normal" conditions you'll have no probems. Thanks, Gary in N.Y.

Gary, thanks for the info. I'm glad I learned all this now rather than @ 6000rpms. Have you seem the stamped OE's break also? I would bet they wouldn't.

i think you just got to chalk it up to "##it happens". i change mine every year since i have seen them break in less than two years service,especially as they have 740 #'s open pressure and since they are only 20 -30 bucks

The more we talk about this the more I find things disturbing...

This is a street motor - I definitely don't want to be changing retainers every couple of years. I'm starting to think this may be a bad idea for my application.

We'll, got it together w/no problems. Took it real easy when installing the locks this time. Hopefully, no more surprises!