"Easyserts" in water jacket side plate holes.

[67c&ccorv]

Hi Don,

Can you tell me what the largest diameter thread is that can be drilled and tapped in the water jacket sideplate bolt holes?

I have been thinking about using an internally threaded product called an "easysert" which can be installed in a tapped and threaded hole. They come pre-coated on the outside threads with a loctite sealant activated when they are threaded into the newly tapped hole and they are also available in 303 'passivated' S/S.

The 5/16" internally threaded "easysert" requires a 1/2" 13tpi hole - is this too big for the material available in the block water jacket holes?

If 5/16" is too large then I could go down to 1/4" and use a step shouldered bolt - the 1/4" "easysert" requires a 7/16" 14tpi threaded hole.

Cheers!

[Don Moyer]

By the time the threads around the water jacket side-plate opening are in trouble, repair bushings with an outside diameter of 1/2" are usually not a good choice (simply not enough good metal remaining around the bolt holes), and if you have to drop down to 3/8", you might as well use 3/8" bolts.

For what it's worth, you're going down a road we have traveled many times in the past, and which has lead to the design of the repair kits in our catalog. We do still stock a 5/16" by 7/16" repair bushing for the occasional time (mostly during a major overhaul) when 7 of the 8 holes are in really good condition and you have unlimited access to do the work of installing a repair bushing in the 8th. For on-boat work, there is frequently insufficient access to do a good (and safe) job of rethreading the defective hole.

Don

[67c&ccorv]

Thanks Don - looks like I will be getting a full kit soon as I am missing one bolt on my water jacket side plate already (pin hole water leak when warmed up) and I don't think the others will come off without breaking.