pipe tap for mercruiser R drive lower shift cable

[charliez]

Getting mixed answers for the correct pipe tap for use on housing to install updated lower shift cable on 67 120hp.
I thought I was dead on with a 1/4 -18 pipe tap NPT but now hear no thats not correct its a 1/2 -13 course thread???? Anyone have any imput. Thanks I have to get past this..

 

[Bondo]

Re: pipe tap for mercruiser R drive lower shift cable

Getting mixed answers for the correct pipe tap for use on housing to install updated lower shift cable on 67 120hp.
I thought I was dead on with a 1/4 -18 pipe tap NPT but now hear no thats not correct its a 1/2 -13 course thread???? Anyone have any imput. Thanks I have to get past this..

Ayuh,... It's 1/4" pipe, but straight cut threads, not the standard tapered cut...

 

[Don S]

Re: pipe tap for mercruiser R drive lower shift cable

but now hear no thats not correct its a 1/2 -13 course thread????

Not even close to true.
Isn't it fantastic the amount of "I hear" or "I was told" or "They say" that is just total crap spewed as fact by people that just don't have a clue about what they are talking about.



.

 

[Eric 3.7LX Alpha 1]

Re: pipe tap for mercruiser R drive lower shift cable

Quicksilver # 91-95639 (goggle it, they're for sale online)

http://www.boatfix.com/merc/Servmanl/6/6A4R3.PDF
go to page 4A 17 which should be #19 of 26 in that link^^^


(HA, Don beat me to it while I was typing. His attachment is that link I have)

 

[charliez]

Re: pipe tap for mercruiser R drive lower shift cable

Yes it is but its hard to ignore someone who says they just finished the job a short while ago & that merc #s that have been superseded by new #s are wrong in many cases . Have you guys actually used this tool ?

 

[Don S]

Re: pipe tap for mercruiser R drive lower shift cable

I've had one in my tool box for many years. Try this link.

http://lmgtfy.com/?q=Mercruiser+91-95639

 

[charliez]

Re: pipe tap for mercruiser R drive lower shift cable

Thanks Don

 

[WashmanToo]

Re: pipe tap for mercruiser R drive lower shift cable

Isn't it fantastic the amount of "I hear" or "I was told" or "They say" that is just total crap spewed as fact by people that just don't have a clue about what they are talking about.

Don. .. ... Yer killin me .. lmao

A variation of the Dryseal thread is the NPSF
(National Pipe Straight Fuel). It is used for
internal threads and a NPTF external thread can
be screwed into it to provide a satisfactory
mechanical connection and a hydraulic seal. The
combination of a parallel and tapered thread is
not regarded as ideal but is widely used.

 

[Don S]

Re: pipe tap for mercruiser R drive lower shift cable

A variation of the Dryseal thread is the NPSF
(National Pipe Straight Fuel). It is used for
internal threads and a NPTF external thread can
be screwed into it to provide a satisfactory
mechanical connection and a hydraulic seal. The
combination of a parallel and tapered thread is
not regarded as ideal but is widely used.

Ok, and your point is what?

 

[WashmanToo]

Re: pipe tap for mercruiser R drive lower shift cable

Ok, and your point is what?

No point, just found your statement funny and so very true.

"total crap spewed as fact by people that just don't have a clue"

When I saw your reference I had to find out what the acronym "NPSF" represented
and thought perhaps others might be wondering as well.