Thread damage/repair on slide hammer?

[JHZR2]

If anyone wants to see the thing in use and why, see this thread:

Diesel injector heat shield nightmare

There’s metal shavings in there on the piston. Ugh!!!! Recommendations on next steps? lock the engine with a bar and spray compressed air into the hole to hopefully blow out the debris

bobistheoilguy.com

I bought an OE slide hammer intended to remove diesel prechambers. The prechamber thread is angled (on purpose), and mine wasn’t in great condition - carboned in hard and bad threads. I threaded the slide hammer in, and with these photos of old and new you can see the angle.

I’m sure that angle didn’t help… coupled with a pretty carboned in prechamber resulted in the hammer threads actually pulling out a few times. I had to put a lot of torque onto the wrench when threading the hammer in. Almost felt like it cut new threads the last time.

Prechamber finally came out, the threads were buggered.

The threads on the slide hammer were fatter on one side too.

I re-oiled the threads, and got the new one on far enough and over the fat threads.

But all that said, should I do something to help shape those threads back to the thinner/sharper form they were originally? I may not need this again ever.. (knocking on wood)… but I have a lot of these cars, and I’d hate to get caught in a situation where next time I need this I have issues. Should I chase these threads? Get a nut with the right Metric thread count/pitch and run it over? Or is it “good enough”?

Thanks!

 

[Astro14]

Those threads are buggered, as you say. A die would cut them back to shape, but material would still be missing.

I’m a thread chaser fan - proper size nut, with a couple of fine slots (3 or 4) cut with a hacksaw to allow any swarf to clear, threaded on will reshape the threads and minimize material removal.

 

[RooflessVW]

IMO leave the tool alone. Don't need to remove any more material

Hopefully you won't need it again any time soon.

 

[Rand]

...

 

[Trav]

You can use the method Astro posted or one of these tools.

https://www.amazon.com/Lang-Tools-2573-3-Piece-Restorer/dp/B007TMEXTQ/ref=sr_1_7?keywords=metric+thread+file&qid=1659703653&sr=8-7

I have a couple of these in Metric, they work well when the end threads are buggered.

http://www.murray.su/images/pmurray.pdf

 

[D60]

The fastener size looks relatively large-ish? 14mm?

I'd source the proper thread chaser if you're concerned. Most nuts fit loosely enough i doubt they'll work all that well as a chaser, but if you have a nut it's worth a try.

I personally primarily use thread files while the work is spinning on the lathe. They can work in-hand depending upon the nature and severity of the damage.

 

[JHZR2]

Thanks all. The prechamber leaked so this idiot tried to hammer it back out when tired and frustrated… forgot to pull the glow plug… broke it off….

But then cleaned everything out really well, got everything back together, and the car is running really well.

Since I have firsthand experience that it still works really well, Im going to leave well enough alone.

 

[ctechbob]

Am I the only one that is a little triggered by Mercedes making the threads on an angle like that? I know it is by design, but I still cringe a little bit seeing the tool in there at an angle, just seems so very wrong.

Glad you got the chamber out though, could have been a nightmare.

 

[RooflessVW]

Am I the only one that is a little triggered by Mercedes making the threads on an angle like that? I know it is by design, but I still cringe a little bit seeing the tool in there at an angle, just seems so very wrong.

Glad you got the chamber out though, could have been a nightmare.

Don't look at the VR6 pistons