Yeah, I Broke aDrum

[AndyClary]

Yes, I knew better. A got a late hogshead that had letter pedals installed. I was told it was rebuilt and o ringed. I should have been more thorough when I found it wasn’t o ringed but I was in a hurry to get my car assembled. The low speed notch and support were well worn and I over tightened the Kevlar band trying to get a good pedal. Now I’ll do it all again.
Not looking for advice, I know what I did. Just putting out there what broke on the Mercury.



Andy

[Kerry]

Like crankshafts, it's not if they break but when, this reverse drum is out of a Canadian marine/stationary built T engine, and shows no sign of ever having or needing a band on it. I'm sure it left the factory pre cracked.

[Steve Jelf]

Kerry is on the right track. A lot of original drums (especially reverse) are cracked.

[Allan]

Just out of interest, on marine conversions of T motor/transmission units, reverse gear is useful. craft can be backed away from moorings before setting out on the water. It is very limited use, but it can be very handy in some circumstances.

Allan from down under.

[Aussie16]

Yes, I knew better. A got a late hogshead that had letter pedals installed. I was told it was rebuilt and o ringed. I should have been more thorough when I found it wasn’t o ringed but I was in a hurry to get my car assembled. The low speed notch and support were well worn and I over tightened the Kevlar band trying to get a good pedal. Now I’ll do it all again.
Not looking for advice, I know what I did. Just putting out there what broke on the Mercury.

Just confirming Andy, you blame the broken drum on the Kevlar band? Hopefully now I have an ally in supporting the fact that the Kevlar band will withstand friction and heat better than the cast iron drum when they have prolonged friction. I have said it a number of times here, but have never had a lot of support? I 100% blame the increase on drum failures on the combined combination of poor driving techniques worn components and mainly the Kevlar band! Prior to the introduction of the Kevlar band to the hobby, I had never heard of a broken drum. Since the Kevlar band was introduced, broken drums are very common. With the old original cotton,bonded or wood linings, they would just glaze/burn and become in effective or would just plain wear out. I had a low pedal get stuck against the floorboard on the way out between low and high. The band rubbed on the drum and then cracked it. I learnt the hard way and now ensure everything is in perfect shape and adjustment. It is unfortunate that a a broken drums mean a complete engine out and rebuild.
Your Mercury is beautiful and I cant wait to see pics of you out enjoying it again soon.

[TWrenn]

Don't blame the Kevlar...blame the operator who won't take the proper time to set them up. I have over 15,000 miles on my '13 that came with almost new Kevlars and no problems. I have them adjusted to "just get the car going" on a slight incline with 2 passengers. It's enough. Too many want the car to jackrabbit start and stop on a dime like their modern cars with power brakes! It AINT gonna happen and ain't SUPPOSED to happen guys! It's a MODEL T for cripes sake. The mostly mud roads helped slow the car even before braking! Drive it like you were in the early 1900's!

[Dan Hatch]

I am installing new drums in mine right now cause of one with 3 cracks. I have never seen a cracked new drum no matter how hot the drum got.
Took a new one out that was black from overheating a guy and no cracks. Dan

[AndyClary]

I’m not blaming the Kevlar, I admitted my mistakes. That said, not to throw gas on the fire, my experience along with a lot of anecdotal evidence will preclude any further use of Kevlar. As has been mentioned bands are consumables, drums are not.


Andy

[speedytinc]

Don't blame the Kevlar...blame the operator who won't take the proper time to set them up. I have over 15,000 miles on my '13 that came with almost new Kevlars and no problems. I have them adjusted to "just get the car going" on a slight incline with 2 passengers. It's enough. Too many want the car to jackrabbit start and stop on a dime like their modern cars with power brakes! It AINT gonna happen and ain't SUPPOSED to happen guys! It's a MODEL T for cripes sake. The mostly mud roads helped slow the car even before braking! Drive it like you were in the early 1900's!

My post is not a pile on of Andy or give him advise. He knows what went wrong.
I post this for others to not fear a properly setup & adjusted use of Kevlar bands. Lets learn from the experience.
Kevlar is unforgiving. Know this & work with it. Kevlar need not be feared, but must be respected.
If you mess up the installation/operation with cotton/scandia bands, you burn up the band lining.
With Kevlar you break a drum. There is that risk.
The upside is Kevlar lasts a long, long time. I have over 10,000 miles on a set with no (Zero) readjustment since the initial 3 or 4 after installation.

How do you prevent a major transmission failure?
There are several "musts" with Kevlar install & use. Not a product for a novice. IMHO.
Lining must sit flat(no lumps or high spots) on a perfectly round shaped band.
Bands must be installed with the H/H off.(not thru the inspection cover)(for above)
Adjustment is NOT done by pedal distance to the floor. There must be no friction before pedal activation. [More to come]
Kevlar needs 3 or 4 early on adjustments until it takes a set. You can not cheat the system by over adjusting.
Its optimal to have a really good low speed cam & notch set. Deal with it while you have the H/H off.
Low & rev. pedal engagement must be solid/firm (no slip)
Braking by a slow pump. Engage, back off, engage. This keeps the band oiled.
"Economy of brake" Use the motor to do most of your slowing. Retard the spark.
Watch conditions ahead. Drive like you have no brakes. Like a model T.
These actions will make for longevity with cotton bands also.

Adjusting low pedal. (Left hand drive or any outside band adjusters)
To get maximum band engagement with no friction before pedal engagement.
Adjust with the motor running listening for triple gear engagement.
Loosen the adjuster jam nut.
Have the motor running @ low idle.
Tighten the adjusting screw until you hear a change in the triple gear song.
Back the adjuster off 1/2 turn.
Your triple gear noise should be gone.
Lock the jam nut.
You now have maximum allowable pedal with no dragging band.
You can also check rev. & brake pedal. Tripple gear noise should change as the pedal starts to cam. There must be no extra noise before engagement.
To check the brake, one wheel must be up with the car in gear running. With a bit of here & there adjusting you can get optimal safe adjustment for these bands also.

[Allan]

Thank you John. I concur with your input all the way. The initial adjustment procedure, step at a time, and again as needed will see kevlar bands providing wonderful service. I put almost 20 000 km on my chocolate van with absolutely no problems. I did change them out at that distance when I had the trans cover off for another reason, but they were still quite serviceable. It just made sense to change them while the cover was off.

I have never used your "listen to the triple gears" when making adjustments, but will try it next time I am in there. I have always done as a previous poster outlines, adjust until they just work satisfactorily, no more. When more is needed as they settle in, again adjust just enough for satisfactory performance. As you indicate, this is a set and forget job once the bands have settled in.

Allan from down under.