I just joined the model T two piece crank club!

[vech]

Last Sunday, my wife and I took our 1915 Touring car out for a drive. We were cruising down a back two lane road at 38 MPH (according to the GPS) when suddenly, the engine sounded like little men, with BIG HAMMERS, where trying to get OUT of the engine. I got the engine removed from the car today, and this is what I found when I pulled the inspection pan. The crankshaft broke in two, just behind the rod throw for number 3 cylinder.... I am going to install a Scat counterbalanced crankshaft in it... And yes, I'm going to get the oil pan checked and trued before I put it back together.

[TXGOAT2]

Cycles to failure?

[George Mills]

Wow! Can’t blame the crank grinder for that one!

[vech]

The engine was built in the 1970's by the previous owner. God knows how many miles they put on it since the 1970's.... I was told it was used on many many tours in California. I put at least 6,000 miles on it, since I've owned it. Stuff happens, things fatigue and break. I am really thankful that the crankcase was not damaged as far as visual inspection goes.. I'm still going to get the block magnifluxed just to check for cracks after that near explosive experience. The car damn near jumped up off the pavement when it happened, before I got it stopped.

[Norman Kling]

This is not a new problem with Model T's. My grandfather drove the NEW route 66 from Los Angeles to the east. Eventually arriving at Plymouth Rock. Then up to Sterling, Ontario and upstate New York and home. This happened in 1926. Somewhere along the way, they broke the crankshaft! In those days the car could be towed to the nearest Ford dealer and the engine was fixed overnight! Then they went on their way.
Norm

[John Dow]

Last October while putting along in my '23 at 25mph on flat ground my crank also let go. The sound was horrendous. Amazingly, no residual damage occurred as a result. The rebuild should be done any day with a Scat Crank installed. Hopefully, she'll run another 100 years without a repeat.

[Roz]

I sure hate to hear this Vech. I joined the club a couple of years ago. I had just turned a corner and was was lightly accelerating when the crank broke. It sounded like a shotgun going off. It broke next to the 4th rod journal and took out the back wall of the block with it. Completely destroyed the block. I had just finished building a spare engine, so I was not down long. Now i'm scared to use anything but a Scat crank in my engines.

[Steve Jelf]

There's an old saying that the question isn't if a Model T crank will break, but when. I decided not to wait and find out. I've had two engine rebuilds so far, both with SCAT cranks. I'll probably do the same on the next project.

[Jim Eubanks]

Welcome to the club. A high dollar crank will break as easy as a std. Its important to find out why and in my experience and others I have seen, its usually a forth main problem with alignment. I threw my ball bearing away!

[vech]

I just noticed, as I was getting ready to take the pan off, that it shattered the rear bearing webbing of the crankcase.
I am now on a search for a 1915 block. This block is not repairable... What a bummer.....

Anybody out there have a good 1915 block they would sell? HELP!!!

Screenshot_2021-06-04_08-38-02.png (442.98 KiB) Viewed 5083 times

[ModelTGal]

There is a 1915 block for sale in the Classified portion of the forums.

viewtopic.php?f=5&t=21333

UPDATE: Of course, it sold 2 days ago!! Sorry...

Jennifer

[Dan Hatch]

I have some non Starter blockers. They may not be 15 but are non Starter and I am in Alabama. Dan

[ThreePedalTapDancer]

This looks to be a 1915 engine on tbay

https://www.ebay.com/itm/393378656573?h ... SwQiFguWLW

[Mark Gregush]

Ouch!! Put an ad in the classifieds, maybe someone close has one. My oldest is 1916.

[david_dewey]

I would not condemn that block so quickly. there are folks out there that can do some amazing stuff. If it were a newer block, I it probably wouldn't be worth the expense, but, as I'm sure you are finding out, pre '17 blocks aren't commonly found anymore.

[speedytinc]

I have some non Starter blockers. They may not be 15 but are non Starter and I am in Alabama. Dan

No need to have a 15 exactly block. Your original casting info can be transfered to a later block along with your original engine #.

[Allan]

Craig, when you tear it down, inspect the cracks in the block closely. On a number of early blocks, and a 1923 one I have seen, there was clear evidence of the block cracking away from the sharp corner where the rear main bolts land. The beginning of he cracks near that boss were polished by movement, while the final break was nice and clean as you would expect. This indicates that the back web breaking out caused the crankshaft to break rather than the reverse. It's no consolation, but it might help others. Certainly, have any block crack tested to eliminate this as a future problem.

Allan from down under.

[vech]

I have the engine completely torn down now. I found another 1915 engine, right here In Mississippi. I want to thank everyone for their help. This is the broken out web of the rear main bearing. When the crank let go, it destroyed the block…

[SurfCityGene]

Hey the bearing looks Good??

I did the same thing with my '12 block over in Kanab 2 tour several years ago and have it running in my car now still and heading up to the National Tour in Spokane soon. I know it's not the normal repair but I "cold" welded it and reinforced it with a JB WELD sandwich front and back bolted together with a plate bolted on each side! It's been doing really good so far.
I have a replacement '12 block but this original one is still going strong... Amazing what you can do sometimes!

[JTT3]

Gene, Any pictures of the repair? I have a 12 block that is broken in the same place

[david_dewey]

I know it's hard to judge by a photo online, but some of that break looks like it was rubbed around. Allen's posting may be what happened.
Sad event, sounds like you have found the parts to fix your car.

[Allan]

Craig, can you post a photo or two of the surfaces of the breakout. If the crack originated from the land on which the main bearing bolts are done up, it may well have been dancing about a bit before it finally let go. If this is the case, the crack next to the bolts will be somewhat polished as it 'worked', while the last bit of the break will appear a clean break. This is not uncommon on the early blocks. I have personal experience of at least 3 breaks of this type.

One engineer in our club had the rear web welded back into the damaged block of his 1912 T. With new bearings poured and a replacement Ford crankshaft, the car is still going strong, so all is not lost.

The machinist in the machine shop I use for all my T engine work indicated that the sharp termination between the back of the block and the face on which the bolts/nuts register, is a perfect stress riser, and the cracks/breakouts I have seen indicate that this may well be the case. He suggested that the transition between the horizontal and vertical planes at that point should be well radiussed, just like the radius employed when the crankshafts are ground.

For this reason, I pay particular attention to that area on any block on which I work. Now I will not do customer jobs without having the block crack tested.

Allan from down under.

[Allan]

John, can we have photos of your breakout as well? The more we can document, the better armed we may be to prevent further examples.

Allan from down under.

[TXGOAT2]

"If the crack originated from the land on which the main bearing bolts are done up...." /// Photo of this area?