MTFCA Forum

Some months ago the crank in my 14 Touring broke. Eventually I replaced it with a Scat but the engine was noisy. To my ears it sounded like a camshaft noise. I checked the end play, only a couple of thou thanks to the Chaffin Kit that mounts on the front lof the cam gear wheel. With the upcoming tour in Sierra Vista, I decided I could not take the car with the noise so I kept looking
When you use the Scat crank with a four dip pan, the counter weights come very, very close to the sump and there is no space for the “U” shaped bars to hold the inspection cover screws. So I chopped the U bar in half and made two “J” shapes.
One just touched the counter weight. On the picture you can see the shiny bit
The camshaft looks fine, I can’t see any rubbing marks though the center bearing may be in wrong way round. So far I can’t find any documentation to which way it goes, but even so it does not appear to touch anything
By the way this gives you some idea of what I disassembled to find the problem.

Is your crankshaft a standard T stroke? I have one in my 26 and don't have a problem. I would suggest that you grind just a little off the J shaped bar in the position the crank touches it.
Norm

There have been enough instances of this to warrant a warning tag attached to the crankshaft to check for such clearance. I know it's not the manufacturer's problem to check clearances, but a heads up to likely difficulties would make for good relations. I found one problem just hand cranking the motor on the stand. It was enough to prevent cranking! The one on my 1925 roadster had no such problems.

Allan from down under.

I knew it would be tight but I’ve done other, starting with the speedster in the 90’s so I was careful. It must be very close as the noise changed when I push the clutch and with new Babbitt the play is probably 4-6 thou it does not make the noise on the starter and I had no problems cranking the motor.
I’ll lie under the motor tomorrow and decide how to proceed.

Is this a problem with only some model year blocks? I have a SCAT crank in mine and have absolutely no issues with it in my '26. Engine number dates it back to the second week of December 1925, So I would guess the motor was manufactured some weeks prior to that.

Tony - paragraph 480 in my 1925 original Ford Service book states "install the notch of the center bearing towards the rear".

Thanks for the position of the notch in the center bearing. I don’t see it in the MTFCA Engine booklet.
By the way, the crank I installed in the Speedster was the one from New Zealand as SCAT was not then available

Did you check the rod bolt heads of the second piston at the camshaft side.

Last year someone brought me an engine with a strange knock. The owner did an overhaul with new crankshaft new rods new pistonsand rings new valves and seats . Since the rebuild there was a knock he couldn't find.

This what I found:



Good luck

Andre
Belgium

My top two suggestions:

1) Crank still is tapping the reinforcement.

2) Rod bolt head is tapping against the cam (Especially if you are using new bolts. Often the heads are too tall.)

I installed a scatt in a 3 dip,I bolted the u bars in without inspection and rotated crank, crank was hitting the rear u a tiny bit so I marked and remove u and ground some clearance

I looked back in my notebook and on the three dip pan of the speedster, the rear inspection pan bolt hit the crank. I cut the U bar into two Js and brazed a bolt into the rear center hole.
I suspect that over the last hundred years the pans get slightly distorted and the fixtures only check the bolt patterns and NOT the depth of the pan. By the time I know everything about Model Ts, I’ll be too old to do anything with the knowledge

I fixed the clearance between the counter weight and the J (were U) irons and put it all back together and the noise has gone.
Now to get the car ready for the Sierra Vista tour. I’ll take the torque wrench so I can check the torque on the cylinder head during the tour.

Glad your engine is fixed and ready for the tour. Have fun.
Norm

Tony, Have a Safe Trip. We'll see you there!

Glad you got it fixed for Sierra Vista. I will see you there.