9.9 stripped fuel pump mounting screw

[Canoe2]

Title pretty much says it all. The motor is a 76 9.9 Johnson. Can’t tighten it up so the pump won’t draw fuel to the carb. If anyone can help me out, it would be greatly appreciated.

 

[racerone]

Helicoil or open it up to the next size bigger screw.----Even consider metric.----Screw is a 10-24 now so a #12 might work.

 

[Vic.S]

If you are up for trying a bit of a bodge that might work.

Clean and de-grease the hole. Very lightly oil or grease the screw but wipe off all excess.
fit the screw without the pump with a dollop of JB Weld. Allow to harden , unscrew the screw clean off any excess JB Weld

Refit the pump but be careful not to over-tighten the screw

 

[boobie]

What Racerone says.

 

[Canoe2]

Thanks. I will see if I can find the proper helicoil or go to the larger screw

 

[oldboat1]

A word for Vic.S's method: I've used West System epoxy with their aluminum powder to do what Vic suggests, and sometimes MarineTex (I use plastic wrap to keep the screw from sticking). It's effective -- but also leaves other options open if necessary. If you muck up the helicoil or bugger up the hole with an oversized screw, you have additional damage to contend with.

 

[thumbnut]

...might be 5-6 threads at the bottom ya might be able to grab on to...if there is enough left use a longer screw..

Otherwise what Racerone said...

 

[Tim Frank]

If you have access to a set of taps and numbered drill set, and are comfortable using them, and have a reasonably well stocked fastener supplier handy, I would try and re-tap the existing hole to 10-32....using the existing bore.
The fine thread should take.

If not, an M5 fastener is next shot. Use a #19 tap drill.

 

[Canoe2]

Hockey last night, baseball tonight, no time for motors yet. Thanks for all the advice, I plan to try the epoxy method first, then move on to the more drastic measures of that doesn’t help. Really appreciate all the input and detailed advice. Feelinguch better about
my chance for getting this old beast back up and running right.

 

[Crosbyman]

instead of rethreads or thread rebuilt with epoxy maybe you can glue in some bolt thread studs directly in the holes with JB weld and use regular lock washers & nuts to bolt down the pump on the studs sticking out the side of the engine

 

[Tim Frank]

^^^^ .... yup....
As brilliant and well-conceived as MY suggestion above may have been ( ), this is a wayyyy better first shot.
I'd grind a flat on the "buried" section of the stud .... maybe even a flat on both sides. That would add resistance to turning....and is simpler than trying to form threads for a machine screw.
It also allows any of the other ideas still to be tried if this does not pan out.

Nice idea!

 

[oldboat1]

Interesting fixes -- but maybe overly complex imo. If you can simply rethread the hole with the original screw, you should be good to go. When the epoxy has partially set up, I like to run the screw up and down a little in its plastic sleeve, then leave it to fully cure.

I've done that post and nut fix, and it works (old boat hulls as I recall). Have also imbedded nuts in epoxy, and used that as a base for screws.

 

[Canoe2]

Oldboat1, when you refer to plastic wrap are you meaning the kind for leftovers or Teflon plumbers tape? I’d like to try that first and work out from there. Weekend is here and the weather looks cold so I may as well fool around in the garage

 

[oldboat1]

Just a couple of layers of the kitchen stuff. If some adheres in the screw hole, that's OK -- just so the screw bites, but can be backed out.