Remove Broken Engine Bolt

[ssn696]

Another useful nugget from YouTube.

 

[Rt Jam]

Good advice ^

A tap is not a chaser.

 

[CopperNick]

+1. Chasers are a special type of tap that are made undersized by a few tenths so that instead of cutting material away from the thread form, they are only skimming the surface and removing scale and rust and general crud. Chasing gets you a clean thread that is still cut to factory or machine grade tolerances. As one source, ARP offers sets of thread chasers in SAE N/C and N/F as well as metric.

After watching that video, the only thing that bothers me is the use of the Kroil on a heated surface. Not sure how they spec their product but some penetrants specifically state not to use their product if heat has been or is to be applied. The heat can cause some kinds of serious chemical reactions that produce toxic/lethal fumes.

 

[69hurstolds]

If you use the standard Chinesium taps/thread chasers, they could be taps, or could be chasers. Their tolerances are all over the map, so you really have no earthly idea which you'd get.

 

[Rt Jam]

+1. Chasers are a special type of tap that are made undersized by a few tenths so that instead of cutting material away from the thread form, they are only skimming the surface and removing scale and rust and general crud. Chasing gets you a clean thread that is still cut to factory or machine grade tolerances. As one source, ARP offers sets of thread chasers in SAE N/C and N/F as well as metric.

After watching that video, the only thing that bothers me is the use of the Kroil on a heated surface. Not sure how they spec their product but some penetrants specifically state not to use their product if heat has been or is to be applied. The heat can cause some kinds of serious chemical reactions that produce toxic/lethal fumes.

In a pinch, I have used taps to clean threads but almost always seen metal.🙁

 

[86LK]

hmmm, keeping a lookout for thread chasers for a Black Friday deal 👍