MTFCA Forum

A fellow bought a 15 touring with a recent "new" motor. Story is he put around 1000 miles on it, but it performed poorly. He rebuilt another motor, switched them out. The old motor was to be repurposed to another T, this is some 10 years later. A bad cam was suspected for the poor running. The cam was pulled & showed nasty wear on 5 of the lobes.(only 5) Why? Then the lifters were pulled. 5 lifters were severly worn. The OD edges hard surfaces cut up the cam lobes. The soft centers of the heads were worn away cupped like a bird bath. I have seen a more severe worn lifler(1) from another motor where the head was completely gone. Only the 7/16" lifter stem remained. The cam was a .270 lift regrind cam.
The loss of lift made for a poorly running motor.

You may recall, a vendor had a bunch of lifters made. The heads were deemed too thick after heat treating. They were reground to spec, but not re heat treated.
These defective lifters keep showing up. The gift that keeps giving.

I found one that all left was a stem. Ruined a Stipes 280 cam.

I taken apart old T engines and found that the original lifters in them some times were still pretty good. Maybe it’s time to start saving good used lifters. Of course they might be some that were slightly worn but not enough to not be reused. Others will definitely have other opinions!

Just WONDERFUL!!!!!!!

Is there a way to tell which ones are the bad ones? Maybe a Rockwell hardness test. I recently got some from a major vendor and would not want to install if they are the bad ones. Jim

TFan wrote: ↑

Tue May 17, 2022 11:44 pm

Is there a way to tell which ones are the bad ones? Maybe a Rockwell hardness test. I recently got some from a major vendor and would not want to install if they are the bad ones. Jim

Hit the ground bottom with a file. If it cuts.......

Jim

in all likelihood, the hardness of your new lifters is fine. This softness problem was a good while ago and typically only crops up now as used parts found in service. As mentioned above, a quick swipe across a non-functional area would tell the tale. That said, over the years I've concluded that none of the lifters I've purchased were ready to use as delivered. Herm Kohnke gives a great photo and word description of getting new lifters ready for use: http://www.mtfca.com/discus/messages/25 ... 1346539048 it is worthy of consideration when putting in a new and expensive cam. Feel free to ignore the discussions that follow in that long and sometimes contentious thread, as they provide little extra information pertinent to your question beyond the advice and pictures posted by Herm.

Correctly made T lifters should be flat on top (with the little divot intact) but they should have a very slight radius on their bottom. They shouldn’t be ground flat on the bottom. The prints are available in Dearborn, MI for anyone to look at.

What Adam said! Herm was a great guy and a good friend, but his opinion regarding lifter faces was jut plain incorrect. Companies like Tobin Arp, Sunnen and Delta would never have designed and built tappet grinding machines if it was a simple as using a garden variety valve grinder to reface a cam follower face.

Thank you Adam and Dan. It’s nice to see correct information posted about lifter design.

Adam and Dan

thank you for correcting the record

are un-square or lumpy faces acceptable as new or is it worthy to face them with a very large radius with proper equipment after purchase? I would think it would be, but perhaps I am in error again!

It's things like this that make all the people I've never done engine work for, very happy! I'll stick to carbs!

thanks again