All Small Six Broken Fitting Advice

[awasson]

Helicoils have been around since dinosaurs roamed the earth. There is another that I used on a motorcycle with a bad oil drain hole. It’s called a time-sert or keen-sert. It’s an insert threats threaded on the outside and inside. You thread the bad hole for the insert and it has the proper thread on the inside. Red thread lock it in place and you’ll be fine. I’ve had it on my motorbike for 15 or 16 years with zero issues.

 

[Frank]

I didn’t want to start a new thread so figured I’d ask here. I’m so close to being back on the road! New radiator, heater hose fitting and all lines in. Last thing was the thermostat. The left bolt on the housing went in fine. The right bolt won’t torque down. Gets close then slips out of the threads and spins. Ugh! I weirdly just put the housing on (without thermostat) and did a water jacket flush. Then when I went to put it on again with the thermostat in it, it now won’t tighten. Is this a re tap job on the block? Open to advice ln this one.

All of the recommendations following your above post ^^are good. You will probably have to rethread the block- but- I have occasionally had the bolt threads eroded enough that I could re-tap the stock size in-head threads to clean them up and use a new bolt. You only need 10lbs of holding force here.

 

[gserafini]

Great advice, doing some more reading on the process and hoping to lock it in this week and get back on the road. Thank you all!

 

[DON]

Tips: keep the drill bit as square to the hole as you can to get it started, once started, it will “find” square by itself.
Apply grease to the tap and most of the chips will stick to the grease.
For blind holes, you can grind flat some of the tip of the tap to get the threads a little farther down the hole. I think at least one holes you are dealing with is open to the cooling passage. You might be able to place a rag under the hole to catch chips