One Inch Crankshaft Bolt, Ford Lehman 120

[Buzz Kuhns]

I have friends who are selling their boat that has sat unused for a couple of years, and I am helping them get it back in working order. Can anyone advise me about the relative importance of the one inch fine thread bolt at the front of the crankshaft on a Ford Lehman 120? It appears to just secure two auxiliary pulleys that in this case are unused, but it seems an awfully big bolt for just that.

I ask because someone stripped it while trying to turn the engine over by hand after it got corrosion-seized last winter. I got the engine un-seized by other means, and there is nothing being driven by the additional pulleys, so if that's the only purpose of the bolt, I won't bother replacing it, because it's an uncommon size/thread that is not readily available out here in the sticks, but if it has some other critical function, I would want to get a new one installed before handing the boat off to the new owners. Any thoughts?

 

[DDW]

I'm not familiar with a Lehman, but what secures the vibration damper pulley on the front of the engine? Some other bolts? That is likely on a taper, and likely held on by that bolt, and you don't want that coming off.

 

[Buzz Kuhns]

Ahh, I think you're onto something there. I'll have to look, but I don't think there are any other bolts on the VD pulley, so that would make sense. As I said it's a pretty large bolt for just a couple of small pulleys.
Thanks!

 

[Comodave]

Check with Brian at American Diesel. He is the Lehman guru. 804-435-3107

 

[Buzz Kuhns]

Thanks Comodave. I spoke with Brian... friendly, very patient with my lack of knowledge. I'll be replacing the bolt.

 

[Comodave]

He is awesome. Very patient and can get you most everything you will need to maintain your Lehman.

 

[READY]

I have the service manual. If you can post a photo I can probably send you the diagram and related info. PM me if you want to send via email.

 

[READY]

Oops...looks like you got what you need!

 

[Bmarler]

That bolt will be very tight. If it’s stripped you’re in for a good fight.

 

[mike66]

To get mine off I used a breaker bar with a pipe and a large wood block. Touched the starter and the bolt freed up without putting a hole in the bottom of my boat.
Make sure you get the engine rotation right before trying this.

 

[Circumnavigator]

As I've suggested many times, McMaster.com stocks 40,000 different fastenings in its 4,000 page catalogue. They will certainly have whatever you need. Great people to deal with, fast service. Same day shipping for orders placed before 1800.



Jim

 

[Buzz Kuhns]

Thanks for the replies, all. I solved the problem by leaving off the auxilliary pulleys that were not in use anyway, and that allowed me to cut off the stripped portion of the old bolt and use the unstripped threads to secure the vibration damper. The boat is now in the hands of its happy new owners.