I use a miniscule amount of loctite on the them when I press them in the briggs small frames, I do a light crosshatch score in a couple of spots around the outside of the guide and seems to be fine. Not sure how the heat transfer will be in the steel guide though.
I have seen on here guys talking about using the bigger briggs guides inserted in the Tec engines, Not sure I want to attempt that with someone else's block right off, not having tried it yet
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Oh and as an FYI, according to Tecumseh's Engine RPM guide that was published in the Microfiche era (mid 1990's), their settings for the RV (recreational) 4 cycle engines were actually aimed at 3900 with a +- of 150. 3600 was more for like snowblowers etc.. Nice fellow by the name of Jake Key scanned the micro's into a PDF document recently on another site. I did a bunch of cross refencing with it compared to Known engine numbers built for mini bike/kart use specifically that are listed and they came up as such, Its interesting to see how many different RPM's ranges they were setting engines at for specific purposes out of the factory.