Repairing a striped plug socket

[LondonNeil]

I've an old 038 super with a striped plug socket that was badly repaired with a helicoil which has mashed up the surrounding flat surface so much a plug won't seal. I've had it ages and been undecided on just replacing the jug, or finding a machine shop to fit a timecert or...?

I've just found these aluminium brazing rods and wondering if the thread and flat could easily be built back up, retapped and the flat machined. Has anyone used them and would they work on the jug?

https://www.ebay.co.uk/itm/ALUMINIU...2349624.m46890.l49286&mkrid=710-127635-2958-0Ta

 

[Marine-piper]

They offer a kit that will completely remove the old threads and re-tap to a larger diameter so you can insert these steel inserts. I just did it to a Homelite XL-12 and it worked. The only issue I had was that my plug was canted not up and down so I had to remove the tip that starts the threading off original threads. The 2nd tool is what I used.

Homelite enthusiast in training [emoji879]

 

[pioneerguy600]

The steel inserts work well, I have done many. I do seal them in place with a dab of Loctite and that seals the threads against air leakage as well.

 

[frank_]

+ 1 on the inserts, if there is enough metal left over from the helicoil
the more expensive timesert ones use a finer thread (same tpi as the plug) and the ebay ones have a coarser outer thread

 

[LondonNeil]

These things
https://www.ebay.co.uk/itm/Spark-Pl...2349624.m46890.l49286&mkrid=710-127635-2958-0Yes I considered those but I'm not sure if since some Muppet already helicoiled it, will there be enough material to fit one? Wurth time sheets do a 'fat sert' that is bigger and designed for just the this situation, but a time sert' kit is not worth buying for one job. However I just thought...I could try the cheap insert, if there isn't material I could build it up with the braze rod and then insert...aha! I wonder if the braze rod would even flow to the insert to braze it in place? Hmm, that would be impressive, unlikely but impressive! TBF I'd be ecstatic if I could just get it to stick to the the cylinder and not melt the cylinder on the process!

 

[frank_]

you would have more chance with the normal worth insert imo, because the helicoil tap is the same tpi as the worth tap,
the ebay tap will follow the helicoil thread for 1 turn then will gouge the thread, because its a coarser 1.5mm tpi/pitch

 

[Maintenance supervisor]

I have Shaun Carr weld it up and retap the threads , he is a fantastic welder.

 

[LondonNeil]

you would have more chance with the normal worth insert imo, because the helicoil tap is the same tpi as the worth tap,
the ebay tap will follow the helicoil thread for 1 turn then will gouge the thread, because its a coarser 1.5mm tpi/pitch

are you suggesting if i just buy a normal wurth time sert, not the fitting kit, that it would thread straight in? I googled and googled but could not find the outer thread size/pitch for the time serts and decided it was highly unlikely it would be the same, but if it is and might work then i think i might be able to get just the insert for not too much

 

[frank_]

are you suggesting if i just buy a normal wurth time sert, not the fitting kit, that it would thread straight in? I googled and googled but could not find the outer thread size/pitch for the time serts and decided it was highly unlikely it would be the same, but if it is and might work then i think i might be able to get just the insert for not too much

yes my time sert tap is a modified sparkplug (4 slits cut and spread outwards) wurth stuff is silly money eh
i think the ebay ones were designed for a (cheaper) normal m15 thread, they are a tad bigger and more suited for a typical stripped thread, that has,nt been helicoiled

 

[LondonNeil]

could be worth a try, a single insert is only £5 or £6

 

[SimonHS]

I believe that the external thread on the M14 x 1.25 Time-serts is M16 x 1.25.

I think helicoils use the same external thread size.

I've got some somwhere. I'll check tomorrow.

 

[pioneerguy600]

Helicoils are roughly 16.40 mm dia while the thicker inserts are 18mm X 1.5

 

[northmanlogging]

I've an old 038 super with a striped plug socket that was badly repaired with a helicoil which has mashed up the surrounding flat surface so much a plug won't seal. I've had it ages and been undecided on just replacing the jug, or finding a machine shop to fit a timecert or...?

I've just found these aluminium brazing rods and wondering if the thread and flat could easily be built back up, retapped and the flat machined. Has anyone used them and would they work on the jug?

https://www.ebay.co.uk/itm/ALUMINIU...2349624.m46890.l49286&mkrid=710-127635-2958-0Ta

Way back when I was a machinist full time, we would regularly weld, redrill and tap holes. That said, you are money ahead to get one of the threaded insert options mentioned above, machining is expensive, welding is expensive, and they both assume that the part CAN be welded, the welder ISN'T a moron, and the machinist ISN'T a hack..

drill it bigger, thread and install insert, can be done at home with a hand drill and some patience

 

[Captain Bruce]

I've an old 038 super with a striped plug socket that was badly repaired with a helicoil which has mashed up the surrounding flat surface so much a plug won't seal. I've had it ages and been undecided on just replacing the jug, or finding a machine shop to fit a timecert or...?

I've just found these aluminium brazing rods and wondering if the thread and flat could easily be built back up, retapped and the flat machined. Has anyone used them and would they work on the jug?

https://www.ebay.co.uk/itm/ALUMINIU...2349624.m46890.l49286&mkrid=710-127635-2958-0Ta

??This is common sense. You have to completely disassemble to make any repair to the jug; just buy a new one?

 

[frank_]

Helicoils are roughly 16.40 mm dia while the thicker inserts are 18mm X 1.5

my stock time serts are 15.6mm dia x 1.25, so they would be a sloppy fit according to that
and my ebay inserts are 16mm x 1.5,

 

[LondonNeil]

??This is common sense. You have to completely disassemble to make any repair to the jug; just buy a new one?

Finding an OEM 038 jug is possible but not simple, and the cost is about £150.

 

[frank_]

Finding an OEM 038 jug is possible but not simple, and the cost is about £150.

in that case, i personally would force an ebay insert into the helicoil thread, with added threadloc
and then i would splay the bottom of the insert with a tapered drift, to lock it in place (from inside the cyl)

 

[SimonHS]

Time-serts are self-swaging.

https://www.timesert.com/
I would take out the old helicoil and then measure the thread in the hole and buy an insert that is the correct size and pitch.

 

[LondonNeil]

my stock time serts are 15.6mm dia x 1.25, so they would be a sloppy fit according to that
and my ebay inserts are 16mm x 1.5,

Hmmm I am not surprised. That brings me back to the braze, although I now think brazing the insert in is the best way to proceed as Google seems to think aluminium and steel can be brazed together.

 

[frank_]

Hmmm I am not surprised. That brings me back to the braze, although I now think brazing the insert in is the best way to proceed as Google seems to think aluminium and steel can be brazed together.

brazing alloy is a rabbit hole imo neil, i think you have 2 choices personally, bodge it or spend a bundle