MTFCA Forum

I added a update to the thread below. on Friday Jan 15th


This project is going to drive me nuts. I have not started the car in over a week. Everything was OK last time I ran the engine. I thought I would start the engine for another "heat cycle" while I was testing all the wiring I just installed.

After the engine ran less than a minute It warmed up enough to settle down and idle as usual. Then in less than a minute, It seemed to "labor" till it died. I thought maybe it was running out of gas, So I checked the gas, and added a couple gallons since it was low. It then started up very easily as it had been before. But in less than a minute it started to "labor" again, and then died. A couple more attempts did the same thing. It runs good for about 15 to 20 seconds it runs fine, and then "labor's" till it dies in about 1 minute or less. I kept thinking gas/carb at first.

After several attempts, I checked the engine with the hand crank. It was very hard to turn ??? So I checked everything . I do my think it is engine related. I think it is transmission related. It only takes a few minutes till the engine will re-start, run less than a minute and then die. If I try the hand crank , it seems to want to try to creep forward, even with the hand brake set. I can not turn the engine with the hand crank for a few minutes. After it all cools off, I can turn the engine with the hand crank again.

So I'm thinking , maybe its clutch disc, or the three thrust washers, or just needs re-adjusted ??? But what could have changed ?? , I have not driven the car yet,
The transmission has all used brass bushings that had some wear, but re-unusable. So they should not be "too tight" The thrust washers were set to the proper measurements, The clutch fingers were properly set using the special gauge, so they are accurately set. The low pedal was also set to the proper "free play" of the linkage.

Ill start trying to figure it out tomorrow, but thought I would ask for thoughts or opinions ....

Sounds like the bands are to tight, back off the reverse and high/low some and see if it will do it again.

Wrist pins?

Ill check the bands tomorrow, and also open the inspection cover to check the clutch finger measurement again.

The wrist pins and pistons were re-used as they were in good shape. So they are already "ran in" I did change the piston rings. The end gaps of the new Hastings rings were at near the limits of max acceptable gap. The gap is closer to "too big" than "too small" but still within Hastings specs.

Since I have installed the engine, I have ran over 3-1/2 gallons of gas thru it. It has cycled thru several heat cycles. I ran it at least 3 times for long enough to bring the water to "steam".

Since this problem started, I am just barely getting it to "warmed up temp" The water in the radiator is just starting to get hot. I can still put my hand on the head and radiator tank.

My feelings are that it has something to do with the transmission. ??

Its just strange to me that it has been doing fine, and then after sitting for about a week it started the problem. ??

I pulled the plugs to look inside. On a Rajo 4 valve head I can see the piston top very well. I can still read the .040 size and see the front arrow. stamped in the piston top. I also noticed I can see the intake and also the exhaust valves as they open and close. I can even see the beveled valve surface when they are open. As well as see the top inch or so of the cylinder wall when the piston goes down .. Everything is clean and looks good.

I see no signs of water leaks anywhere, like when the head gaskets leaked water the other time I had a problem with this engine.

The only things I have done to the car since it was running good about a week or so ago is: I changed the front axle from stock to a drop center axle, adjusted out my steering linkages and set toe-in, and installed all the wiring harnesses. That's it. Nothing at all that should affect the engine/trans.

I can honestly say that I have rebuilt many model T engines in the past 30 or so years. I have never had as many problems with any engine I have ever worked on or rebuilt. This one is the most problematic engine I have ever seen.

OK I've vented enough .... Time to go to bed

Perhaps put the rear axle on stands and put it in high gear?

Les S's suggestion should be the first test! If it is the transmission, and the bands are not dragging severely, it should run okay with the rear wheels safely off the ground. If it labors and stalls with the wheels off the ground, and the bands are not dragging? That eliminates almost everything else in the transmission and clutch because all those things lock up and spin as a unit in high gear. Under those conditions, I would suspect the pistons are too tight, given that the wrist pins and rings are pretty well not suspected. But it could be any of those three things. The pistons are oversize (.040)? Were they used in this block before? Or was the block bored to fit used pistons? (I would certainly do that!)


An added thought. In my experience, dragging bands usually do not react by getting bad as the engine warms up, and then get better in only minutes after it is shut off and can cool a bit. There isn't much in the bands that can have that sort of a thermal reaction. It IS possible, but unlikely from my experience. That is the bugaboo of tight pistons, wrist pins, or faulty or mis-fitting rings. Those things get very hot due to the nearby combustion and friction. They do have considerable expansion under the best of conditions, and any ill-fitting in them very often has this sort of reaction.

Jacking up the rear end and put it in high gear as suggested and see if it runs ok. If it does, theres a pretty good chance that your triple gear bushings might be starting to seize on the shafts. Did you rebush the triple gears or fit the existing bushings to new pins? How much clearance did they have?

Dan McE, He said that the bushings were used, and a bit but not terribly loose. Even so, you are right that the gears and/or bushings could be seizing. Thanks for the additional support for testing that way.

By the way. What are you doing wasting time at this hour?

I had thought about putting the rear end on blocks and test the transmission that way. I may have time to do that today.

All the transmission bushings were used. The triple gear pins are also very nice used. I also made sure they were tight in the flywheel.

I do not have a magneto ring or magnets. I am using Dan's. triple gear pins lock ring to keep the pins from backing out.

The .040 pistons are used and already ran in. They were in good condition. All I did was replace the rings and do a light hone with my glaze breaker.

Thanks for the input.

OK, Now I know this thing is possessed !!

I got the rear of the car on blocks today. So I thought I would just do a quick startup to warm it up a little bit. It started very easily as usual Took about 30 seconds to warm up enough to take off partial choke, and it just ran as it had been. With the hand brake set to hold the rear wheels it had no indication of any problem. I let it run a few minutes and then let off the hand brake to the neutral position. The rear wheels would turn but I could stop them with my hand. So that indicates just normal "oil drag" I tested the low pedal and it worked perfect, with very little to no gear noise. It is quieter in low than my 27 tour car that was re-built to within a inch of perfect. I tested the reverse pedal. There is a little gear noise but less than normal for all used parts. The brake pedal would stop the rear wheels with no change to the engine at all. I continued running the engine for about 20 minutes. It was just starting to show steam at the overflow of the radiator. So I had it to full operating temperature.

So this brings me back to "this car is possessed" I have no other explaniation ??? It acts as if nothing at all happened yesterday ???

I did take a few pics, one is of my new "dip axle" that I needed to clear the hand crank and a couple of the "Craveroiler" upper cylinder lubricator in use. First pic is of " valve closed" "no vacuum" then "valve open" "a little vacuum" I ran it for about 2 minutes with the vacuum valve wide open and never did smell the Marvel Mystery Oil or see any smoke. Ill have to play with it some to figure it out ...

Anyway, All seems to be well in speedster land again .... Thanks for the input, its always appreciated ...

Donnie, your front axle reminded me of the one I used in my speedster. It had been in some kind of horse drawn vehicle and was fitted up side down to get the cart higher, perhaps to improve the drivers view! To add extra height, the axle was given what we would call a drop. Then they adjusted the camber by introducing a similar curve to yours between the perches. It really was a neat front axle when fitted in a speedster.

Allan from down under.

I had a simular thing happen to a newly rebult engine. I found that the rear cam bearing was too tight and caused the engine to grind to a halt after it warmed up a little. DON"T rev the engine beyond a low idle until you find the problem. If it is the rear cam bearing, all of the engine torque is routed through the length of the cam to the frozeen rear bearing to kill the engine. High RPM in that situation probably would have destroyed the cam shaft. IMHO

I have read of a rear cam bearing that was a bit too tight. It seized onto the camshaft and spun in the block. Repairing the blocck after it was discovered was quite difficult because the wear in the block was not even or centered.

It sounds like you fixed it, Donnie. Good clean living pays off again!

Mike, I believe it may be because I hooked up the lubricator for the Marvel Mystery Oil. The "mystery problem" just needed some oil.