How easy is it to strip the plug threads on a Yamaha outboard. I’ve done plenty of mechanical work in my day…but I don’t have a torque wrench and it always makes me nervous. I used a 8” ratchet and deliberately thought not to overtighten….but I don’t want them to vibrate out. Am I being overly worried or does it happen often. Thanks for the heads up
Striped plugs on a yamaha
- Thread starter Noble Savage
- Start date
blindmullet
Well-Known Member
I have always used anti seize and don't use the handle on the ratchet. If it makes you nervous spend the $30 and get the wrench.
I've never used a torque wrench on any plug ever. I'm not saying it's bad to do it, but I think it all comes down what you're comfortable with and your experience. Tighten till you feel it bottom out and then a 1/4 turn-ish more. If you have any doubts, though, get a torque wrench. It's a good tool to have, anyways.
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There are some applications where never seize is not recommended, check the technical manual.
Regarding spark plugs, it is easier to correctly install new plugs vs reusing old ones ( a different discussion topic). For new, tighten till hand tight and until you feel the crush washer crush. Then add a 1/4 turn.
In general though, it is good to use a torque wrench even if just to learn what different torques feel like. It is very easy to over torque small bolts. In addition if you will be doing any work like cylinder head works, head covers, etc, you have to use a torque wrench. Although I don't use a torque wrench for things lke spark plugs and t-stat housings, I do use one when installing my props, always
One brand of motor specs 40 foot pounds and the other specs 80 ft pounds. When I do the 40 ft-lbs it feels too little and when I install the 80 ft-lbs props it feels too tight!
Regarding spark plugs, it is easier to correctly install new plugs vs reusing old ones ( a different discussion topic). For new, tighten till hand tight and until you feel the crush washer crush. Then add a 1/4 turn.
In general though, it is good to use a torque wrench even if just to learn what different torques feel like. It is very easy to over torque small bolts. In addition if you will be doing any work like cylinder head works, head covers, etc, you have to use a torque wrench. Although I don't use a torque wrench for things lke spark plugs and t-stat housings, I do use one when installing my props, always
One brand of motor specs 40 foot pounds and the other specs 80 ft pounds. When I do the 40 ft-lbs it feels too little and when I install the 80 ft-lbs props it feels too tight!New plugs made the boat fire up like a champ. Thanks for the input. I will buy a digital torque wrench for the future. It’s not a money thing, I just have not learned to trust them yet. We’ve all stripped stuff and broken bolts and such. That’s when we learned that too much was too much. But I don’t want to strip an outboard…so it’s time to buy a quality wrench. Thanks again for the advice.
I don't trust the coating on the plugs.