I'm in the process of putting a new Zoom clutch (part #30006) in my '67 Camaro and have run into a strange problem. The clutch I'm replacing is a Zoom MU-5505-1. Here's the set-up, I have an 11" flywheel from Ricks, new pilot bushing, new fork from Ricks, and a 621 bellhousing. The current clutch engages and disengages fine. When I put the new 30006 clutch in it would not disengage. I took all of the free-play out of the clutch pedal and it would then disengage if I pushed the pedal all the way to the floor, and I mean all the way. I took the 30006 pressure plate out and used the new clutch disk with the MU-5505-1 pressure plate, and it disengages fine with 3/4" free-play in the clutch pedal. So, with the MU-5505-1 pressure plate installed, I pushed the throwbearing against the pressure plate fingers measured from the throwout bearing to the transmission hole in the bell housing and it measure 1 1/4". I then put the 30006 pressure plate back in and took the same measurement and it measured 1 1/2". So, I think this is where my problem. Has anyone every run into this problem before? Both pressure plates are the diaphram type plate.

Sounds like you are on the right track. Before I finished reading your post, I was thinking: throwout bearing. Get the one that is correct for your set-up and you should be ok.

I thought throwout bearing too. However, I'm using the short one which is an 1 1/4" and the long one is 1 7/8". I think that extra 5/8" would be to much. Also, I measured from the ball in the bellhousing the fork attaches to and it is the correct 4 3/4" distance to the front of the bellhousing. I was thinking it needed adjusting, but it works fine with the MU-5505-1 pressure plate.

fork

The fork is a new fork from Ricks for 67-69 Camaros. Ricks part number CL-12.

do you have an old one to compare it to?

Many vendors are supplying a second gen fork, it don't work. The correct fork is still available from GM.

do you have an old one to compare it to?

Many vendors are supplying a second gen fork, it don't work. The correct fork is still available from GM.


Agree with what Jim says - I ran into this issue with installing a Tremec kit in my 68 and relayed info. back to them that it was wrong fork and doesn't work properly. They seemed to agree and exchanged with a stock GM fork so have hopefully changed the kit offered to avoid frustrating future customers. Also - I didn't think the Lakewood adjustable pivot ball they spec'd worked well with the GM fork either (ball was too wide and flat on top which hindered the pivot action) so went to original part on that as well. This was a heavy duty Lakewood fork and even the tech guy from Lakewood said that it wouldn't work in First-Gen applications yet this is what the vendor was supplying in their kit. It cost me several days of agonizing frustration before I figured out that it couldn't possibly work well. They worked with me on it and provided good customer service, but was a concerned that they had been spec'ing this fork for who knows how long and not sure why it wasn't an issue raised before. What I noticed was that I couldn't get the geometry to jive and the bulkiness of the heavy-duty fork caused clearance problems with the back of the bellhousing.

I have the original fork that I replaced and it is exactly the same as the one from Ricks. I don't think the linkage or fork is the problem as the MU-5505-1 clutch works fine.

I figure the forks aren't identical is what's going on!

I know my new re-popper is bigger than my stock fork so check it CLOSE!!

pdq67

I figure the forks aren't identical is what's going on!

I know my new re-popper is bigger than my stock fork so check it CLOSE!!

pdq67

uh huh. Put the original fork on the original ball, bet it works right.

The CL-12 fork Rick’s sells is the correct part for a first gen Camaro so that is not your problem. You should also have the short (1⅜”) throw out bearing and a medium length (1½”) pivot ball. Your flywheel should be at least .960” thick. To measure the flywheel lay it face down on a flat table and measure from the back of one of the bolt holes to the surface of the table. If all of these measurements are correct and it still won't disengage, then the new pressure plate is the problem.

The MU-5505-1 pressure plate is correct for your car. I have this same PP in my car and it works great. :thumbsup:

While it’s apart you should also replace your "new" pilot bushing. Zoom uses cheap Chinese pilot bushings in their clutch kits. If a magnet will stick to your pilot bushing it has iron in it and you should not use it.

Napa stores carry a 100% bronze heavy duty pilot bushing. The part number is BK 6151161. Unlike the cheap pilot bushings the 100% bronze bushing is easy to install, won’t gall your transmission input shaft, and will last longer than the clutch. For only $3.29 it is good insurance.

Napa also carries the junk iron pilot bushing for $1.69. Don’t buy this one. :noway:

Thanks Steve b/c that's good info to know!!

pdq67

I want to thank all of you for the help and suggestions. I also wanted to give you an update. I called Summit, where I purchased the clutch, and explained the problem. The tech guy said the pressure plate was defective and to return it for a new one. I returned the clutch and have received the new one but have not yet installed it. I'll post again once I put the new clutch in.

I want to thank all of you for the help and suggestions. I also wanted to give you an update. I called Summit, where I purchased the clutch, and explained the problem. The tech guy said the pressure plate was defective and to return it for a new one. I returned the clutch and have received the new one but have not yet installed it. I'll post again once I put the new clutch in.



Damn!!.....Thanks for the heads up on Zoom clutches, I don't believe I would have wanted another one!, what if the same thing happens again?.....That's alot of heavy hard labor!.....I'll stick with Hays Clutches!:yes::thumbsup:

I have the same problem with my Zoom mu series clutch not disengaging.

The one I put behind my 496 fit fine.

pdq67

Steve has some great info and I would like to add that the Camaro 1-1/2" tall transmission mount under NAPA is BK 6201030. The 1-1/2" tall transmission mount gets mixed up quite a bit with the 1-7/8" tall one.

Lately, we had the same thing with a Zoom clutch and a NAPA clutch, luckily we caught it before we installed it in the vehicles.

We always compare all of the new parts to be replaced with the existing old parts. As others mentioned, the fork should be the same in appearance and shape. The height of a new clutch/pressure plate along with the TOB should be close to the same height as your original. As practice, we never install any clutch/pressure plate/TOB greater than an 1/8" difference of an original unless we have an adjustable clutch pivot ball.