LC60291 – Part 4: The Mechanicals
Now that the coupe looked brand new, it was time to make the drive match the looks. Step #1: shift pins. I knew I was completely out of my mechanical depth with that particular project even with Vinci’s awesome DIY. I contacted another local coupe owner, Alex (the up and coming “Randy Forbes” of Colorado ). I knew he had done the shift pin service at least once before, and he also happened to still have the drift tools. I then contacted Jonathan Thayer of BimmerDiffs.com to order up a shift pin service parts kit and some Amsoil for the transmission and differential. He was nice enough to expedite the shipping to make sure I got everything in time.
When Alex came to swap coupes (yep, I now have his in my garage too ), I had him take it for a test drive with me to see if he felt anything we may have missed. In the first corner he mentioned that the rear shocks had to have been replaced (which we later confirmed). He also noticed some minor clutch slippage. He suggested we just do the clutch too since we were dropping the transmission for the shift pin service anyway. We all agreed.
We took a good look through the engine bay where he confirmed the new cooling system components and m50 manifold. He also agreed with our previous assessment that aside from the headlights, everything else up front was original with no sign of previous damage. I’m pretty confident that it was never in any type of accident. The chrome-ringed headlights remain a mystery.
It was an especially easy to make the decision to replace the clutch because the previous owner of the coupe had included a brand new one with the car. He said when he had first bought the coupe, the low clutch engagement had made him think the clutch was on its way out before he later learned that the low clutch engagement was normal on M Coupes. To be honest, I never noticed any clutch slippage on my test drive, but agreed it made sense to make the change given the transmission was being dropped anyway. The included clutch was an F1 Racing brand, stage 2 clutch kit. Stage 2 was probably overkill for this particular coupe, but the online reviews for this specific clutch were positive (I did come across some problems on Honda and Mazda forums). I packed up the hatch with the shift pin kit, Amsoil, and clutch kit, and Alex took the coupe back to his garage and lift (what service!).
It all started out well. The transmission came out fine, but Alex noticed the flex disc (guibo) was soft enough that he could flex it by hand. That’s no good, so we got a new one. No big deal. The shift pins for reverse and 5th were locked in place which explains how horrible it shifted. He finished the shift pin service and moved on to the clutch. Removing the old clutch went fine. It appeared to be the original clutch and was in good shape for the mileage but obviously showing its age and mileage. It was time for a replacement anyway.
Alex got out the new clutch kit. It seemed to be pretty well made. He lined it up following the sticker showing which side should face the flywheel and immediately noticed a problem. Once reassembled with the stock flywheel, the clutch disc would most likely weld itself to the throwout bearing guide tube when started. Was it on backwards? We did some more research and came across this thread. In it, it was suggested that you do install the clutch in reverse of the directions when not using an aftermarket flywheel. That seemed pretty sketchy. Alex called the clutch manufacturer, and they said their kit would not work with a stock flywheel. Well, I guess a new, stock clutch was in order then.
I called the local dealership in hopes of being able to obtain one quickly and get the project completed. The parts manager recognized my voice, offered me a discount, and said he could get one by Friday. The problem was that their retail price was $575, and my price was $470. I pointed out that Turner Motorsports sells the kit for $336. He looked it up and confirmed it was the same kit. He said his own cost for the kit is $427, so he had no idea how they were selling it so much cheaper. He advised I just go with them this time since he could not compete with that price. I decided overnight shipping would be worth it this time, and placed my clutch order yesterday afternoon. It was already out for delivery to Alex’s house this morning. Crazy!
Because we don’t have a ton of history on the car, we also decided to “reset” the maintenance clock by flushing all the fluids and doing an oil change. As previously mentioned, we’ll have Amsoil in the transmission and differential, as well as doing a brake and coolant flush. It should be good to go for a long time to come.
So unfortunately, this does not wholly conclude the “Mechanicals” portion of this project. Alex has to work at his real job the next few days. Final results should be in on Saturday. I can’t wait to drive it again!
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