There was a discussion awhile back about someone finding a mag plate that came loose and was still driving the car. We had a long discussion about it being a bad thing to drive with "anything" wrong in the trans. At the time I could not find the photos I had of a friends 1921 TT truck engine that blew up on him. He was lucky as it was winter time and he had on a full set of Carhart coveralls and gloves. When the engine blew up it destroyed the firewall, destroyed the coil box, destroyed the floor boards, They are what saved my friends legs when the entire transmission drum assembly came up thru the floor. When I say "destroyed" I mean it tore them to little pieces. It even broke the neck off the starter. It broke the flywheel into several pieces. And five quarts of hot engine oil instantly covered every square inch of the inside of the cab. There were parts under the truck, in the truck, beside the truck, and we believe one of the triple gears went thru the door panel because that is the only thing we can think of that made a 4 inch round hole all the way thru the door panel... Sorry there are no pictures of the truck. I took these pictures of the engine after we removed it and brought it to my house for repair. These pics were taken before I started taking anything apart. All the damage was done by the explosion. So this is just a reminder to not take the transmission condition for granted .... have fun and be safe Donnie Brown ...
Impressive amount of carnage. Worst I have seen by far!
Any idea at what speed or RPM this occurred?
Looks like a grenade went off in there!
Now that's a true interpretation of an engine that
I've seen T's eat magneto's but like Royce.
Worst I have seen by far!
It would be interesting to be able to retrace exactly what order those things happened, and how much warning, such as noise, vibration etc led up to the Big Bang!
How is the crankshaft? Sudden stoppage probably severely damaged that also.
40 years ago, no camera with me to get photos. At a Turlock swap meet, a fellow brought a similar engine for display only (he had found it in a barn a few weeks earlier). I remember looking at it like it was yesterday, and have mentioned it on several such threads on this forum.
It wasn't even half that bad.
Thank you for finding and sharing the photos!
Definitely, the worst blown up T engine I have ever seen!
Drive carefully, and enjoy, W2
These were actual photos taken back when all I had was a camera and film. I thought I also had a photo of the transmission drum assembly, but I can not find it. The transmission drum assembly came out as a complete unit and landed in the seat beside my friend. I say "friend" but he was a new local TT owner who actually was a close friend of a friend of mine. The truck was a very nice original wood, 1921 closed cab TT, with stake bed. It was a very, very nice survivor truck. The owner had never driven a T or TT before buying the truck. My friend, who was our mutual friend was a Model A guy. I believe they had the truck turning excessive RPMs as they were trying to learn to drive it. I was able to salvage the entire engine assembly and replace the oil pan/crankcase and all the destroyed parts to have a good engine again. The crankshaft was not hurt in the least bit. I did not even have to do a facing cut on it. They replaced the fire wall, floor boards, coil box, fixed the hole in the door, and cleaned up dirty oil for the month it took me to re-build the engine. I installed the engine and drove the truck for about a week before I tried to teach the owner how to drive it. The truck drove great. In all my years of teaching someone how to drive a T, that man is the only person I could not teach. He never could grasp the function of the clutch pedal. There were lots of times he would just stomp it to the floor when driving along in high gear, and the engine would rev up severally. (that may be how he blew it up) I asked him several time why he did that. He always said he was wanting to hold the clutch in neutral. ?????. The day of the training I adjusted the bands out twice. He had burnt them that bad. It was just awful. So after a few hours I decided to call it quits, before he blew up the engine again with me in the truck. I just could not bear the abuse the poor old truck was going thru. I adjusted the bands one final time and drove it onto his trailer for him. I told him in all my years of working with Ts, I was going to have to give him "failing marks" in driving a T and told him the best thing for him and the truck was to sell it. He said he would sell it, as in his opinion all Model Ts were a piece of s%&# and could not see why anyone would ever want one. As to what failed, and cause this much damage. I never really found a "smoking gun" type of sign. It could be that the flywheel had a crack and the flywheel broke causing all the damage, but I could not see any sign of a "old crack" anywhere. I feel like it probably "slung" a magnet clamp, and that set off a "chain of events". Just thought someone may want to see probably the "worst Model T explosion ever"
It sure looks like the flywheel let go. Appears that the hogs head was thrown up & out from the engine end. Once the wheel went the works followed. I never would have believed that much damage was possible. The driver sure had a guardian angel looking over him that day.
You wouldn't think that 20 HP could do all that damage. Inertia can be a powerful force.
My thought is, that severe high RPM caused that. He stomped the left pedal down at road speed, and the flywheel became a pizza.
Donnie. Your observation;
"There were lots of times he would just stomp it to the floor when driving along in high gear, and the engine would rev up severally"
I think that says it all. Notice at least two of the splits in the flywheel intersect the triple gear shaft holes. I suspect the severe load on those shafts in combination with excessive RPM just shattered the flywheel.
I found a pic of the truck I took on the day of the driving lesson. They had already fixed the damage to the door and also repainted the door and firewall, as well as fixing the other damage... . It was just a nice old original truck, before the damage happened ... The photos are dated 2002, so I guess it was about 14 years ago ...
Wow that's a lot of damage. Its amazing what can happen when your not careful and don't know what you're doing.
Donnie, looks like that owner skipped the air bag recall. Don't worry though, that'll buff out!
I agree that it looks like the flywheel exploded. It may have been from him stomping the pedal down resulting in excessive RPM, or the extra stress on the triple gear pins, or maybe a magnet keeper or some other foreign object tried to go through the triple gears.
I once worked on a Ford LN700 with a gas engine that had suffered a clutch explosion due to excessive RPM. The pieces of the pressure plate, clutch disc, and flywheel, destroyed the bellhousing, came through the floor, put a hole in the roof, cut both exhaust pipes in half, and nearly cut the frame rails in two. There was a triangular piece about the size of a slice of pie imbedded in the CB radio. I was told that the driver had a nasty cut on his arm, but not much else. Lucky guy!
Now we know why they put transmission blankets in race cars.... he was very lucky indeed...next time I need one I want to borrow his Guardian Angel
Jeff. Your comment about the LN700 triggered a thought about this one. The extra weight and the low rear axle ratio of this TT are no doubt factors in this catastrophe. The neophyte owner (being VERY generous here) was probably running at the TT's top speed in high when he "stomped the pedal". All of the force needed to accelerate the flywheel to high RPM would have gone through the triple gear pins. A Model T car would have likely skidded the rear tires, but the extra weight of the TT over the rear wheels allowed more of the kinetic energy to transfer to the moving parts of the engine resulting in the disintegration of the flywheel and in turn the rest off the transmission.
The owner/former owner proved beyond a doubt that he is well qualified for one of the upcoming self driving cars
WOW! Now that's a blown engine, literally! Sounds like the guy driving didn't know how to work the pedals as my Mother use to say when her Father in the 20's was teaching the family how to drive a T.
By the looks of the flywheel it probably was the first thing to develop cracks and that was it.
Goes to show what can happen to these old engines when they are overwound!
I asked the owner of the truck what it was like inside the truck when it happened. He said "it was over before he even knew what happened". The only injuries he had were two big bruises on top of his legs. Probably where his legs hit the steering wheel when the floor boards pushed his legs up. He said he "thought his knees went behind his head". He also had a big bruise on the bottom side of his right forearm. and a few small scratches on his face. He wore glasses so no hot oil got in his eyes. The coveralls saved a lot of injuries from happening. Just a very lucky and blessed man. I don,t know if anyone noticed, but it also broke of the exhaust manifold off...
How did the sump portion look? Shows how brittle cast iron is.
Greg, the sump was beat up pretty bad. There were lots of small dents and some large dents that were shaped long and narrow. There were just a few small holes in the bottoms of some of the dents. It looked like a "sack of walnuts" .
I'm just curious, but rather than selling the truck could your friend have avoided his clutch operating issues by removing the low band altogether and installing some kind of auxiliary transmission? Seems to me that would get you a low gear and a normal-ish clutch.
I'm not advocating it, just wondering if anyone's done it.
My God, Talk about wife abuse!
Martynn Vowell was asking the questions several months ago about the missing plates that hold the magnets. He has since (wisely) yanked the engine and has it all over his garage waiting for some key parts.