Odd sized pressure plate bolt??

[Baja71]

When I took apart my clutch, the pressure plate had one bolt, about 1/4 shorter than the rest. I wouldn't expect that. Any reason, or should I chaulk it up to the PO and get a matching length? My concern is balance.

 

[bronko69er]

Yes, a present from the PO.

 

[Baja71]

Dang it!

thanks!

 

[Broncobowsher]

It could be a lot worse. I have seen some that were drilled out and had larger bolts stuffed in.

 

[67ster]

Pressure plate bolts are a special shouldered bolt. The PO probably lost one and used a standard capscrew -- not cool !

 

[Baja71]

They all look like regular threaded bolts. What should they look like and why?

Pressure plate bolts are a special shouldered bolt. The PO probably lost one and used a standard capscrew -- not cool !

 

[fordtrucks4ever]

Sorry, my stupid!!! Was thinking about another thread. You are most likely right about being replaced by just a 5/16 bolt. They look just like a regular bolt with a longer shoulder and slightly less thread for its length. The shoulder is not undersized for clearance like a standard bolt. Dont really notice much difference untii matched up with just a regular bolt.

 

[Viperwolf1]

That shorter bolt, if a not just a hardware item, was likely one for a flex plate from an automatic. Doesnt mean it had an auto at one time, just that someone has been into it before.

I believe he said it was a pressure plate bolt, not a flywheel bolt. But it does show that someone was in there at least once before.

 

[Baja71]

Are we talking about a long shank? All 6 of these bolts were fully threaded. One was shorter overall. I went and bought 6 fully threaded grade 8 replacements. Should I install something else?

Sorry, my stupid!!! Was thinking about another thread. You are most likely right about being replaced by just a 5/16 bolt. They look just like a regular bolt with a longer shoulder and slightly less thread for its length. The shoulder is not undersized for clearance like a standard bolt. Dont really notice much difference untii matched up with just a regular bolt.

 

[Baja71]

Yes, I'm talking about the pressure plate bolts.

 

[fordtrucks4ever]

If you notice the bolt holes in pressure plate, the threads are recessed down about 1/8" or so. The bolt shoulder serves as an alignment pin and fits with minimul clearance in pressure plate and centers in flywheel with no shear load against threads. Sorrry this sounds more complicated than really is.

 

[67ster]

Couldn't have 'splained it better ! Shouldered to keep the shear off the threads. ARP/Summit/Jegs or the dealer most likely will have them . I prefer to get them all started and progressivly tighten them to keep from warping the cover.

 

[fordtrucks4ever]

Just about any local hotrod shop will have them. Way to common not to. Same as whats on my 1941 Ford 9N tractor.

 

[Baja71]

Ok, thanks guys. Sounds like I have a project for this Sat. AM. As, I said, the bolts I pulled out were threaded from head to tip, no shank or shoulder, so whoever did the last clutch just grabbed bolts out of an old parts bin or something. Glad I started this thread, as I had a set of 6 shiny new grade 8s with no shank or shoulder to replace them. I'm sure it would have been fine for quite awhile, but that would have been a crappy reason to have to pull the tranny and clutch down the road.

The other thing, as it turns out...I'm replacing the flywheel (50 oz) from Tom's and the pressure plate (LUK). The bolt holes that line up for the pressure plate are a larger diameter (fatter) than on the stock flywheel. Will I find "Ford" pressure plate bolts in this diameter, or will they only come in the factory specs?