NewEnglandFormula

hello all. took my stock clutch out at 90,000 miles. had the stock flywheel resurfaced and put it back together with a new mcleod clutch kit, just a street level one, P/N 75016. fired it up and it vibrates bad when you rev it up. took it back apart and double checked everything, didnt see anything wrong. Ran the engine with just the flywheel on it and it ran smooth, no vibration. what gives? thank you in advance

BALLSS

Is your motor rebuilt, or just the CC503??

if so and the motor is now internal balance you would need to have the PP zero balanced

NewEnglandFormula

Just a cam. Motor is stock otherwise.

BALLSS

McLeod and all the other clutch companies use the same "clone" PP. What I have noticed over the years is these PP often do not have the balance holes drilled in the outer 3 tabs of the PP like the original Valeo were.

While I have never had a issue with several different clutch brands with a stock external balanced motor these ones that do not have any balancing done to them may be the problem

Only way to confirm would be to take the old PP and new one to a machine shop and have the McLeod match balanced.

The stock FW would have a cast in weight on the back side and some drill hole in various places to balance the FW. The stock replacement Valeo PP had a paint dab that you would align to the dowel pin in rear of crank. Now every clone clutch has no paint dab

I have a rebuilt motor so mine is now internal, aka neutral, balanced motor so I have taken every clutch I have used on this combo to a machine shop to neutral balance the PP to a already separately neutral balanced aftermarket FW. Typically the shop takes off 25-30 grams of material to balance mine...that's about a ounce of weight

Weird your stock motor is not happy with the McLeod. I have their Street Twin and have been to their shop and feel they make a great clutch

You checked with just FW and it is vibe free but with PP it is not...I suspect there is a balance issue with the PP that needs to match your old original clutch. Again a weird situation as I have always just bolted several brands of single disc clutches with no paint dab to note orientation and never had a issue with a stock external (rear) balanced LT1.

Pics of balance holes in one of my clutches I had before gong to the Street Twin for a reference as to where the holes would typically be drilled to balance it

NewEnglandFormula

My PP does not have those holes drilled in it anywhere.

BALLSS

...and the one you took off..does it have holes drilled?? (could be 1,2, 3 on one or more of the ears of the PP and at different hole depths)

If so you have a balance issue of the PP in comparison to the one that came off.

Given you ran the motor FW only that takes the FW balance out of the equation

You will need to pull clutch out. You could roll the dice and just 180 it and reinstall so its balance may then land close enough for the FW counterbalance weight to absorb the difference but obviously that is a crap shoot call. Given how much effort it takes to swap a clutch I would have the PP balanced matched to the old one.

Again not a common occurrence but it appears to be the issue you have. The clone PP everyone uses is offshore and from what I have seen are no longer balanced to whatever factory specs the Valeo originals were

Balance would likely cost about $40 at a machine shop. They would likely need your FW too depending on what kind of fixture they have on their balancer machine to be able to mount a PP

You could call McLeod and see if they will exchange the PP (shipping and costs will cost more than to have your current one balance matched)....you may or may not have this issue with one from McLeod or another clutch company. This clone off shore stuff is always a crap shoot

Running the motor like this will start a RMS leak and beat on the rear main bearing when it is out of balance

NewEnglandFormula

My stock valeo one has holes drilled. The new McLeod does not. I’m going to call McLeod and see what they say

NewEnglandFormula

I ended up sending the mcleod back and getting a RAM powergrip and that pressure plate had the yellow paint mark. so I lined it up with the paint mark on the stock flywheel I had resurfaced and put it back together. ran great and I love how clutch is now like and on/off switch.

BALLSS

I have seen some clutch kits using the non painted PP that has a yellow paint dab indicating install orientation. IDK if they use NOS Valeo PP or balance the clone cores to spec. But yeah....balance matters on clutch replacement on stock external balance LT1's

I have a internal balance motor so have to get any new FW or PP "neutral" balanced. Even if the part is advertised as "neutral" balance I have the machine shop check....every time they were not and by as much as 26 grams.

The cast hat & friction plate and the rest of the components of the PP vary in terms of balance "as assembled" so they need to be balanced as a assembled unit to match factory specs. That is why every original clutch had various drill holes and had a alignment mark, paint dab, for install to correlate its balance with the weighted balance of a stock FW

Aftermarket clone offshore parts....lose some of the finer points....like balance but sadly are often the only available replacement part....