manifold drain plug screw threads stripped

[ziggy]

hi folks, 1972 165 hp, IL6, mercusier 250 cid. well, got up the nerve to take someone elses pipe nipple and coupler off my manifold, thats what my manifold drain plug was screwed into. the nipple pipe that was steel and screwed into the manifold was leaking. i'm hopeing to stop that. here i go. guess its a 1/8 nipple screwed into the manifold, it's way to loose, female screw threads either rusted away or stripped by someone else. gone none the less. i want to get any opinions on what way i can get a new 1/8" nipple pipe screwed in secure enough to not leak, will put a coupler on that and drain plug to coupler to seal it. question is what to use to get the pipe to stay in the manifold. JB weld, probably not, high temp silicon??? maybe. another thought i had was to tap to the next size up, thinking that may not be to good of a idea as next size up is 1/4. anyone got any good ideas short of R&Ring the manifold, the obvious proper repair. jim

 

[steve n carol]

Re: manifold drain plug screw threads stripped

Ziggy, JB weld could work if it's not too loose. Or you drill to the next larger size and tap it out! It should be accessible, (thats the hard part). Myself, I would tap it out. I am not a plumber, but I think you need pipe thread type taps...sl

 

[RedRangerVIP]

Re: manifold drain plug screw threads stripped

Loctite makes some epoxy that is high temp and also impervious to about anything. You might go to their website and do some investigating. You might look here on Iboats in the maintence section of The Mall also.

 

[RedRangerVIP]

Re: manifold drain plug screw threads stripped

I just thought of something else. Parts store should have a coil insert kit that ought to fix it also.<br /> Good luck!Let us in on what works for ya.

 

[Flames]

Re: manifold drain plug screw threads stripped

Heli Coil is the way to go and not very hard to install.<br /><br />my2cents<br /><br /><br />Rudy

 

[tommays]

Re: manifold drain plug screw threads stripped

there is no helicoil for and NPT thread only NPS<br /> <br />first thing i would try is to run in a 1/8 pipe tap the thread is tapered and unless a lot of metal is gone there should be a good chance at cleaning up the threads <br /><br />if not<br /><br /><br />it would be very easy to go from 1/8 to 1/4 npt cast iron taps very easy and does not require any taping fluid<br /><br />dont buy a cheep hardware store tap they are only good for thread chaseing <br /><br />brands like hanson and other inports are barely good enough to clean up a thread a good tap will have ground threads and be so sharp it can cut you<br /><br />tommays

 

[ziggy]

Re: manifold drain plug screw threads stripped

thanks folks, these are really good ideas. as i look closer at the situation i see that i will not be able to run a tap much more than maybe 3/8" deep into the manifold before i hit the other side of the manifold. bummer. i tried running a 1/8" NPT tap in it to clean up the treads, not a hope, tap bottoms out on the inside of the manifold. So, 1st try i think will be to clean up whats left of the screwthreads in the manifold. gonna up permetx hard gasket sealer on a new 1/8" nipples, gonna cut off the small taper to the new nipple so it don't portrude into the manifold to deep. couple it and put plug in it. won't know if this works till next season as i'm started the winterizeing prossess. next best guess if that don't work is to go up to 1/4 NPT. wow, bummer the boss on the manifold probably will let me tap it, but not by much i'm guessing. i don't like the corser threads on the 1/4 NPT either. seems like anything oversize is gonna have to corse of screw threads too. so at this point it's still a punt as to how it worksout. thanks for the input. all were very good ideas. i sure do like this forum, it's great to have a thousand boaters ideas,,,,, jim.

 

[ziggy]

Re: manifold drain plug screw threads stripped

well, got'er gooped up and put together. i'm not hopeful,,,,, i just think unless the forma gasket firms up good it aint gonna hold. it just barely let me snug it down before starting to strip. hand tight even. time will tell. jim

 

[Bondo]

Re: manifold drain plug screw threads stripped

Run a 3/8ths"/16 tap through it,+ install a Goopped Up 3/8ths" bolt in it.............<br />I don't Think you'll even have to drill it out.....<br /><br />I Think you'll find 3/8ths/16 is the Next Sized, Threaded Anything, That'll fit in that Hole.........

 

[crazy charlie]

Re: manifold drain plug screw threads stripped

I did the same repair a few years back.Clean it up and use marine tex and set it in before it hardens.The repair is still good about 5 years later.Charlie

 

[crazy charlie]

Re: manifold drain plug screw threads stripped

By the way you may want to build it up a little on the outside to give you a little more holding power.Charlie

 

[Buttanic]

Re: manifold drain plug screw threads stripped

Loc-Tite makes a product for stripped threads in non critical applications. You can find it at any auto part store.