Hey guys. So Im slowly working through the parts I received with my 24 coupe and just making list of things I need to do.
The deal came with 2 engines: a 1924 and a 1926. Both appear to be in excellent shape and neither appears to have been touched from original. Cylinders on initial inspection look great and both turn over easily.
Now, apart form disassembly, inspection, new rings, gaskets, etc. What triggers most of you to do a complete rebuild including re-babbiting and boring/honing?
Tom, my main trigger is being able to afford a complete rebuild. With four broken crankshafts over many years in our fleet of Ts, we tend to do the job from scratch. If you can work with what you have you are in luck. However, there is no point in doing just parts of a recondition. New pistons, rings and a rebore are wasted if a crank breaks and takes out the rear web in the block. Likewise, re-grinding a crankshaft and pouring new main and rod bearings is a waste if the crankshaft is not crack tested and found sound. Even then, bad things can still happen.
I guess my message is save up for a Scat crank, and build up from there. Then drive the pants off it.
Allan from down under.
Having driven T's for over 40 years and many thousands of miles (and I don't baby them), I've so far suffered no catastrophic failures. I am probably tempting the fates by saying this. Hopefully it doesn't bite me
If you have the original two piece valves, replace them. They have been known to come apart and ruin a piston or head. As for the cylinders, you can mike the cylinders to determine whether they have been re-bored. Most pistons have a number stamped on the top which tells what undersize it is if it has been re-bored. Most important in fitting rings is whether the cylinders are tapered or out of round. If so they need to be re-bored. Same goes for the crank bearings. They should be round and not tapered. When ordering rings, you need to know which rings will fit which type piston and also the size of the bore.
I would suggest that you purchase from the club the booklet "engine" Also the ones on "Transmission",and "Electrical System" These will give easy to understand specifications and instructions on how to overhaul or rebuild these parts. It is important to get the engine, magneto , and transmission right because most repairs require pulling all three out as a unit and if you get all three right, you will not need to pull things as often.
On one hand, a great many Model T's see plenty of driving with their original crank shafts. On the other hand, it's been said that the question isn't whether it will break, but when. I would base the decision on usage. If the car will be driven only around home occasionally, rings and valves may be good enough. If you intend to do some serious driving, save up the dough for a Scat crank as Allan says, and get the works.
If you don't replace the crank, then at least magnaflux it. I have/had a nice running 14 that was babied in my ownership and driven infrequently by the prior owner (from the 1950"s). The crank broke at an idle while I was trying to locate a miss in the engine.
I base the decision on three things: usage, funds, and the "aggravation factor". If I will use the car regularly, have a full wallet, and don't want to be stuck on the side of the road with a dead engine (aggravation factor), I go in for the total rebuild. If not, I'll settle for a good running engine and save the cash for other projects.
Just remember to drive it right. You can spend a Lot of money on an engine and still have a broken crankshaft or whatever only because you thought you could drive it faster and harder.
It's happened more than you think.
Tom F. - I think what Steve and Kevin both said is "huge"! "A lot depends on usage"! If you intend to do any long distance and fairly hard driving on tours and such, that's one thing! But if you just intend to putter around town and make an occasional run down to the ice cream place and such for fun, keep in mind that with careful driving, a very worn out engine will continue to run well for a long, long time with the light use most of us give our Model T's. Some of the sweetest running Model T engines are pretty well worn out, and they'll just keep on, and keep on as long as you keep enough oil in them! FWIW,....harold
Thanks guys! Very helpful information and something to give some thought to.
My thought is this
1. If you get an engine running, just enjoy it. I did this to start. Then felt I could make improvements... at some point into that I felt I needed a rebuild. Five years later I have not got back on the road.
2. If you have money/time then get a restorable core. Then spend time/money on the restore the engine and at the same time enjoy the car until the engine is done.
My 2 cents.