Tapping Bell Housing for shift cable

[Fishermark]

On the project boat I am working on... 1972 Sea Ray with Mercruiser 165 and Model 1 outdrive. I will be putting a new shift cable on soon. I believe the cable on the outdrive now is the old style that is threaded on from the inside. I know the new cables thread in from the outside and it is my understanding that I need to tap the hole to accommodate this. A couple of questions...

... Is the tap needed a 1/4" NPT tap?

... Does the cable for an Alpha 1 fit?

 

[tommays]

Re: Tapping Bell Housing for shift cable


1/4 NPS




Tommays

 

[achris]

Re: Tapping Bell Housing for shift cable

On the project boat I am working on... 1972 Sea Ray with Mercruiser 165 and Model 1 outdrive. I will be putting a new shift cable on soon. I believe the cable on the outdrive now is the old style that is threaded on from the inside. I know the new cables thread in from the outside and it is my understanding that I need to tap the hole to accommodate this. A couple of questions...

... Is the tap needed a 1/4" NPT tap?

No, you need a 1/4" NPS (Straight thread, not taper). Part number from Merc is 91-95639

... Does the cable for an Alpha 1 fit?

Yes.

Chris........

 

[ziggy]

Re: Tapping Bell Housing for shift cable

No, you need a 1/4" NPS (Straight thread, not taper)

so..... does that mean that mercstuff ain't sellin the right tap? "http://www.mercstuff.com/shiftcable1.htm" whats the consiquences of useing the npt. cause it looks like that's what's bein sold....... and that's what i used.....

 

[achris]

Re: Tapping Bell Housing for shift cable

from the Merc service notebook

 

[achris]

Re: Tapping Bell Housing for shift cable

so..... does that mean that mercstuff ain't sellin the right tap? "http://www.mercstuff.com/shiftcable1.htm"

Yes... that's a tapered tap... that's why they say "by running this tap from inside of the bell housing to just 4 threads short of the end of the tap."

This is not the right tap

whats the consiquences of useing the npt. cause it looks like that's what's bein sold....... and that's what i used.....

If you ran the tap all the way down, then the hole is now too big... It will not tighten up properly and will probably leak water.

Chris.............

 

[ziggy]

Re: Tapping Bell Housing for shift cable

sounds like ya ask a real good question there fishermark....... save yerself the grief i got. maybe i am lucky i can't read though...... i think rodbolts the one that first gave me the idea that i had used the wrong tap.... achris ya just proved i can't read. i taped from back to ft and not all the way thru. only till the nut almost contacted the bellhouseing. maybe i'll be lucky. i'm not usually. it did tighten up.... seems like there was a fairly high toque spec on that nut that i got....... sure wish i'd a seen that mercruiser service notebook statement prior to doing the deed. i'm sure learning not to trust anything that i see that ain't oem written..... now i'm gonna wonder..... rats. that's two threads ya've done fishermark that i have found something after the fact that i've done wrong....... sorry to highjack yer thread..... least ya know the facts now........

 

[Don S]

Re: Tapping Bell Housing for shift cable

Mercstuff isn't the "FINAL WORD" for Merc information. They also say it's ok to replace only part of the gimbal bearing.

 

[ziggy]

Re: Tapping Bell Housing for shift cable

Mercstuff isn't the "FINAL WORD" for Merc information. They also say it's ok to replace only part of the gimbal bearing.

they certainly aren't...... guess i aint to smart. fool me once (gimble brg) shame on you(them), fool me twice (npt vs nps). shame on me....

 

[Alumarine]

Re: Tapping Bell Housing for shift cable

I notice the instruction sheet from achris indicates "water may leak into bell housing" if done incorrectly.

What will happen if water does leak into the bell housing?

 

[starsnstripers]

Re: Tapping Bell Housing for shift cable

Geesh I hate to use you two (zig-fisher) as guinne pigs but you two are a few steps ahead of everything I need to do to my L6 165. I noticed the outer casing is cracked open on the bottom of my shift cable. It works but I'm gonna change it out while engines out. Thanks for the post Chris. Here's an idea--- Scince the holes are already tapped and the threads will hold ok, Maybe take the cable back out and either put some teflon tape or a good sealer on the threads and reinstall? Shouldn't leak then.

 

[Don S]

Re: Tapping Bell Housing for shift cable

I notice the instruction sheet from achris indicates "water may leak into bell housing" if done incorrectly.

What will happen if water does leak into the bell housing?

In a word, corrosion, especially if in salt water.

 

[Fishermark]

Re: Tapping Bell Housing for shift cable

Well, I'm glad I asked before I did the work. Sometimes edujacation is a good thing!

 

[achris]

Re: Tapping Bell Housing for shift cable

... that's two threads ya've done fishermark that i have found something after the fact that i've done wrong.......

So, did we learn anything? Like 'If in doubt, ask'?

Maybe?

Chris.............

 

[MikDee]

Re: Tapping Bell Housing for shift cable

they certainly aren't...... guess i aint to smart. fool me once (gimble brg) shame on you(them), fool me twice (npt vs nps). shame on me....

Don't worry ziggy, there's always J&B weld, or even better salt water corrosion It ain't the end of the world man

 

[Alumarine]

Re: Tapping Bell Housing for shift cable

In a word, corrosion, especially if in salt water.

Thank you Don, I guess I'll find out if I tapped mine correctly.

 

[ziggy]

Re: Tapping Bell Housing for shift cable

So, did we learn anything?

yep, trust my oem service manual and any service bullitin or service notebook updates only......

Don't worry ziggy, there's always J&B weld, or even better salt water corrosion It ain't the end of the world man

almost though .... i appreiciate the comment.....i aint to worried... maybe i should be and don't even know it yet....i missunderstood the mstuff instrucions. i tapped from the back. i tried my cable and it wouldn't bottom, so i tapped it deeper.. till i got the nut to almost flush with the bellhousing. didn't tap all the way thru... seems like it tightened up real good.... i also used some perfect seal on it if i remember.... if it leaks i guess i'll know why.... but my guess w/o knowing is it won't....time will tell....

Like 'If in doubt, ask'?

yep, i usually do.... i always got questions...... in this case. there appears to misinfo on the www...... hence i didn't ask.... also i didn't read correctly... that no one can help me with..... maybe not understanding or readin correctly will save my bacon this time. i hope so..... hope others can learn from my mistake. bet fishermark won't make the same mistake i did.... which is what this forum is about...... hows the sayin go. experience comes from making bad desicions....something like that.....

 

[achris]

Re: Tapping Bell Housing for shift cable

.... hope others can learn from my mistake.....

I was once told "A man who makes no mistakes, makes nothing".... Very true... I thought I was wrong once, but I found out I was mistaken....