Anecdotes Wanted - Pulling My Engine for the First Time

[ryanf1023]

Hello all,

I’ve been a frequent lurker and infrequent poster for a long while now. Months ago, I made the choice to pull the engine on my car. The initial plan was finish the body, drive it for a “bit”, then do all of my mechanical work later. And I simply don’t work that way. If it means another year or two off the road to do it right, so be it.

For context, I bought a running chassis in Spring 2024. I’ve been building my own speedster body since then, which has been the thrill of a lifetime. I’m about 80% done the body, but have reached the point of needing to tackle mechanical work while the body is in the state it’s in. I’m comfortable with disassembly, reassembly, etc of pieces, although I don’t do machining, metal work, or welding as of yet.

I’m curious as to what kinds of cans of worms the forum population has experienced when pulling an engine. Does everything lead to rebabbiting? Does everything lead to new triple gear bushings? Are cases of adjusting bearings and a few other checks normal? Does anybody open an unknown engine and go “wow. That’s actually not bad!”?

I’m not looking for shortcuts, simply stories and experiences of what can happen, typical or atypical, in pulling and opening up an unknown engine.

Thanks,

Ryan

[varmint]

Straight answer to your question: “wow. That’s actually not bad!” after it sat for decades.
And if something is bad, you deal with it. I had to replace the magneto, starter, plugs, all wiring, but the engine still had hone marks and good compression.
Before taking it apart, I would change the oil, turn it over by hand and then do a compression test...go from there.

[Chris Barker]

One thing that's not obvious. Check crank end float before you start.

If it's under about 0.010", things are looking good.

[TXGOAT2]

I'd run it. That's the best way to assess your engine, magneto, radiator, ignition, carburetor, etc. It's best to run it in a drive-able chassis, but running it several hours in the frame will be revealing. With rear axle and wheels in place you can get some idea of how the transmission performs, but driving it would be better. Run it with clean 5W30 detergent oil in it and ThermoCure cooling system cleaner in the radiator.
In building the body, I'd want make clearance available for removing the cylinder head and accessing the crankcase dip pan and transmission cover and other service points without undue difficulty.

[Gene_French]

Ryan:
Pat is right about running the vehicle to determine the overall condition of the various parts ... assuming that there is no obvious conditions present that dictate caution ...you will likely want to do some disassembly to service the thrust washers in the rear axel and to check condition of the bearings in the engine ... i would suggest that too many people imagine that extreme precision is necessary in a Model T engine/transmission unit ... you have probably read of pistons sleazing and rods burning out ...most often due to TOO LITTLE clearance not too much clearance ...you can build your car using your head and hands and good judgement or you can build with your check book and the advice of others ...the photos indicate a high degree of craftsmanship and care in the wood body work ... continue on that path with the mechanical ... careful care with alignment and fit will yield good results ...a vision of the end product will guide the build ... if you want a practical era correct speedster you have a good start ... if you want a NASCAR racer you may want to update to a more current model ...Gene French

[TXGOAT2]

Model Ts have no oil pump to force oil into the bearings and they have wide crank and rod bearings, so some clearance is necessary to allow oil ready access to the bearing surfaces. Use of multi-grade oil, such as 5W30 or 10W30 will facilitate bearing lubrication. I would not hesitate to use 0W20 in a newly rebuilt engine for the first 200 miles. Multi-grade oil will also give good clutch and band action, and it may help prevent triple gear bushing problems. I have an idea that using detergent oil will help prevent transmission band glazing.
The Model T engine was designed with wide crank bearings of fairly small diameter. This kept both weight and rubbing speeds down while providing a lot of bearing surface. The weight of the crank throws and crank pins was critical in an engine that lacked any counterbalancing, with less being better.

[ryanf1023]

Thank you all. I so feel both enlightened and calm after reading the replies.

The notion of too much clearance is often better than too little is something good to remember. As well, thinking of the entire system as a whole is something that I could have overlooked.

My magneto field coil ring (rebuilt by myself) has got me thinking: has anyone ever had their flywheel magnets contact the field coil ring poles while in motion? Does that necessarily lead to catastrophic failure, or can it be a gradual series of squeaks, wear, resistance, etc.

[TXGOAT2]

The crankshaft main bearing end play is important to obtaining correct magneto air gap spacing, and assembly of the magnets must be done carefully to get them all the same height. I believe a gauge is used to do it. If the job is not done right there is potential for big trouble. The same is true of positioning the "4th main" bearing at the back end of the transmission.

[Rich P. Bingham]

Likely TMI . . .
My first love was a 1920 cutoff touring derelict that had been driven into the ground and left outside with the hogshead removed. As a wide-eyed 14 year old, my perception of “restoration” was to disassemble everything, clean it, paint it, and reassemble.

Pulling the engine was accomplished with the help of two buddies on either end of a corral pole chained to the motor between the cylinders, and balanced by yours truly at the starting crank.

I was fortunate at that time (1962) to have access to Douglass Machine & Bearing (est.1919). After disassembly and “sanitizing”, Mr. Douglass straightened the crankshaft, turned the flange to remove the “dishing” that had worn at the third main, built up the end of the third main cap to eliminate end-play, and pronounced the cylinders true enough to accept new rings, and the mains and rod bearings sound enough to be re-fit to the crank.

With the Ford factory manual in hand, I checked the transmission bushings and (near as I could reckon) within serviceable tolerances. The whole, clean and re-assembled came to life, and served me well through two seasons. Eventually the engine was entirely re-built, bored, and new bearings poured.