ERA #294 Clutch Problem / Recomendations ?

[sracer5]

Lost my clutch a block from my shop. I knew my hydraulic system was weak so I expected that my Clutch Master and /or slave had let go. My car has a McLeod aluminum flywheel with an 11 inch Hayes clutch & pressure plate. Driving I felt a soft click like the master let go and then the clutch wouldn’t release. I raised it at my shop and tried to adjust the hydraulics with no luck. I decided to drive it home 20 miles and had no issues starting in 1st and shifting to 4th with no clutch release.I ordered all new clutch hydraulics from Peter and installed them today . I installed everything and bleed the system. I have right at 1/16 slave to clutch arm and close to 1 inch free travel at the pedal. Still no clutch release , I’m thinking I lost the disk or partial pressure plate ? Has anyone ever had the pivot point for the clutch arm fail and cause this ? Throw out bearing is completely quiet in our out. Lastly any clutch recommendations when the transmission comes out ? ( looking more likely by the second ) - May be time to ditch the flywheel also and go with an iron one. I don’t track the car ! Thanks for any ideas!

[Argess]

I finally changed all my clutch parts last year, but before I did, there was a suspicion that the pivot had started to loosen.

I originally installed the pivot back in the 1990's and it wasn't easy. The countersunk rivets come through the pressure-plate from the outside and it's difficult to peen them over on the inside. Try swinging a hammer in a bowl. I heated mine so that after peening, they would shrink tighter.

Anyway, mine turned out to be fine and I noticed the pivot was very thick steel. Nonetheless, my clutch book does mention about the pivots cracking and show a fix.

No doubt after welding the gussets in, peening rivets would be very difficult. I see that pivots often come now with countersunk (allen) bolts and nuts.

It appears you have no recourse other than to take the clutch out which is quite a job in an ERA. You'll find out what's wrong then. If you're really curious, you may be able to see through the clutch fork bell-housing hole with a flashlight, or better still, a boroscope.

[blykins]

If you do switch flywheels, go with steel, not cast iron. Cast iron will crack and it’s a general liability to hotter cars.

I would recommend either a RAM or McLeod clutch. The part number will depend on the trans you have and how much power you’re making.

[Argess]

I switched from a McLeod Long Style P-P with a full organic disc to a RAM diaphragm P-P with a combination metallic/organic disc.

At first I looked at Mcleod, but the metallic side of the disc faces the flywheel, and I didn't want any damage to the flywheel thinking it might be similar to how metalized brake pads score a rotor. I'd rather replace the P-P than the flywheel....

Additionally, the organic side doesn't like heat, and the flywheel is a better heat-sink than the P-P.

So I went with RAM which has the disc sides reversed.

This is the kit I used with my Richmond Gear 5 speed, Lakewood Bell-housing, and FE:

https://www.summitracing.com/parts/RAM-98969T

ps: I forgot to mention in my earlier post, that if your pivot was riveted on, and the rivets weren't tight, there would be flexing and subsequent metal fatigue and the rivets could be broken.

[DanEC]

I doubt the flywheel is a problem and I like aluminum flywheels - have three of them in various cars right now. The pressure plate however could be an issue. I've seen reports and photos where they have come apart. Are you able to get someone to watch the fork end while the pedal is fully stroked to verify the fork is stroking full distance with it?

If the pivot failed I don't think the pedal and TO bearing movement (such as it is) would be quiet or smooth.

I lean towards McLeod clutches although some think they can be a bit heavy. Ram is another good choice. It's sort of a personal issue due to a new, but very bad Hays flywheel I once purchased - but I have a low opinion of Hays products at this point.

Teardown is probably where you have to go next. I pulled the Toploader in my ERA last year and rebuilt it and if you plan to do this yourself, here are a couple of suggestions. I bought some all-thread in the size of the bellhousing to trans bolts and cut four lengths about 8 or 9 inches long. Once the trans bolts were removed I screwed the all-thread sections in, put a jack under the engine pad (with plywood and carpet protection) to raise it slightly, pulled the transmission mount and then simply slid the transmission back on the dowels to where it was sufficiently out from under the dash and I could get a good grip on it and lift/drag it over on to the floor towards the door where I could carefully lift it out. Before that I cut 5/16" plywood to place over the floor on both sides and the center frame area to cover and protect the carpeting and frame.

Before tear out of the clutch though I would make sure the hydraulics are working and the fork is stroking fully. Maybe there is some air in the slave line. If that bleeder isn’t fully rotated to the top of the slave cylinder, all the air can’t be bleed out. But you probably know all that.

[RockBit]

I have a McLeod billet steel flywheel and McLeod dual disc clutch, as recommend by Blykins. It works really well and the clutch is fairly light effort.

I also have the pins DanEC is talking about, as I made them for my install.

Let me know if you want any help and I’ll come over.

[sracer5]

Looks like the pressure plate failed. I used my borescope to look at the throw out bearing and pressure plate. One pressure plate arm is touching the throw out bearing the other is relaxed. I watched the throw out bearing move and it just barely touches the relaxed side at full throw. 😥 Thanks for everyone’s help.

[sracer5]

[img]db0521d5-c337-4b77-8de5-91a9d7091005[/img]

[blykins]

You need a good McLeod or RAM clutch.

[sracer5]

I’m planning on another McLeod clutch. The McLeod clutch is 30 plus years old in the car now , just hope a new one will match the thickness of the old one so. Don’t have to adjust much. The 3 old fingers on the pressure plate seem to have bolts in the end that can be adjusted . All the new ones I have looked at don’t have any adjustment there.

[DanEC]

I would not use a long style pressure plate. I would go with a diaphragm McLeod clutch - probably a Street Pro. Ask Blykins for a recommendation

[blykins]

You have to pay for an adjustable pressure plate and they can be a pain, as your belhousing needs to have holes in it for adjustment. Better to just go with a non-adjustable piece.

With Long style and Diaphragm plates having roughly the same static pressures these days (not like it was in the 60's/70's, when we were looking at 3000-3500 lb pressure plates), I don't really have a negative feeling about Long style plates, but it just depends on what style actuation is used and what fork is used.

For instance, with older factory Ford cars, the Long style is preferred as the mechanical linkage will over-center a diaphragm plate. However, on a Cobra, with some cars using passenger-side pivot balls, or hydraulic bearings, then a diaphragm pressure plate seems to be the better solution.

I routinely use McLeod and RAM. High quality pieces. Can't say that for some of the other brands.

[sracer5]

I contacted McLeod racing today. They offer a rebuild / refurbishment service. I’m thinking about sending them my clutch disk and pressure plate and having them refinish them. That way I won’t have any issues adapting a newer style clutch. Anyone here used this service before ? Seems like it will be a good solution for me.

[DanEC]

Not McLeod specifically but a friend with a Hemi Roadrunner with a long style clutch had it rebuilt by an old driveline shop mechanic locally and it’s been fine. If you have been happy with the clutch up until now, that’s an option. But, I had to return a pressure plate to McLeod once and the shipping is fairly expensive.

[sracer5]

Spent about 2 hours pulling the interior and transmission.Went faster than i thought it would ! Anyone changed the clutch arm from the old pin style to the open hole style ? I have the new style adjustable pin from Peter and have ordered the arm from speedway parts. Looks like it will simplify the installation and adjustment.

[GaryT]

I just went through this in January, pivot bent over. I wish i had seen post #2 about reinforcing it sooner but its all back together now. I went back with the same pivot from Quick Time and put a new arm and bearing in it. I have a Pond block so the ERA supplied slave cylinder mount was always off and used this time to re-design one. I also removed the 7/8 master and went back to the 3/4 since i gained more travel, cut the peddle effort by more than 1/2.

[DanEC]

Originally Posted by sracer5

Spent about 2 hours pulling the interior and transmission.Went faster than i thought it would ! Anyone changed the clutch arm from the old pin style to the open hole style ? I have the new style adjustable pin from Peter and have ordered the arm from speedway parts. Looks like it will simplify the installation and adjustment.

Guess I’m not familiar with your question on the clutch arm. Do you have any pictures of the difference?

[patrickt]

Originally Posted by DanEC

Guess I’m not familiar with your question on the clutch arm. Do you have any pictures of the difference?

I'm not familiar with that either. It's hard to tell from the small pic of the fork, but do you still have to trim the corner off the fork so that it doesn't hit the master cylinder reservoir cap?

[GaryT]

The picture of mine does have the corners clipped off but i don't think it would have hit, my original one was done so i copied it.

[DanEC]

My car #782 cleared just fine. Not sure what the difference would be except I have a QuickTime bellhousing.