Reply To: Helicoil Insert/Install – Intake Cover TD20

[John Gragg]

aquasonic wrote:

The intake cover also handles exhaust on the “T” series Johnsons. The solid threaded inserts are good, but the ones I’ve seen are larger in diameter than the Helicoil insert. You may not have enough thickness at the mating surface on the motor side. The 10/24 Helicoil definitely works, but even that doesn’t have much extra room. I recall using 1 or 2 on a TD-20 intake/exhaust cover successfully. Use the exact size cobalt drill that the kit recommends.

For sealing/locking in the threads, red loktite works well. Make sure that the Helicoil threads are slightly below flush on the drilled hole so as not to interfere with the screw installation. Don’t over sink the Helicoil either. They are not designed to back out. Take your time, and check as you go. Once installed, don’t forget to break off the tang as per the instructions.

 

 

Thank you. Yes, my first order was the EZ Lok type since, as Crosbyman stated, they are solid inserts. But as you commented, there is very little room on the thin wall where this insert/screw is going. I don’t remember what size drill and tap they included in the package, but it was large enough that there would be almost no metal left on the sides of the screw. Sent it back and ordered the Helicoil. The helicoil is much smaller and gives me room to drill/tap. The drill size is only 13/64, so I’m good.

I was thinking about it last night. Although I’ve never had the enjoyment of stripping out a spark plug hole, I know many who have. Helicoils work just fine in that application, so I’m sure I will be fine in this instance. And yes, I plan to use locktite red on the helicoil and blue locker on the screws like Crosbyman says.

Thanks for the reply.
Best Regards,

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

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55 Johnson CD12. Sold
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