Proper tell tale location for my Johnson V-4

[BonairII]

Another one of my winter projects is adding a tell tale to my '67 Johnson 80hp. I'm doing for two reasons...First: to eliminated air pockets/hot spots in the water jacket. Second: I'm tired of running along on the water and periodically having to ask my son "can u see water coming out of the back of motor?".

I just ordered the parts(elbow, hose, and bulk head fitting). Just have to find a 1/8" pipe tap and 11/32" drill.

I've read the sticky on installing a tell-tale, but I just want to be sure I install it in the optimum location.

This location is my first choice (cyl #1 behind the head)

This is my 2nd choice (cyl#1 IN the head itself)

The pics are of my '67 parts motor, so I'm going to drill into this one first as a dry run cause I haven't drilled/tapped a hole before. Seems pretty straight forward, but I want to make sure I can do it properly BEFORE drilling into my good motor.

What should I use on the elbow threads? Teflon tape?

Tips? Suggestions?

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

Just went out and bought a tap/die set and a drill bit. I just realized that the Tell-Tale sticky has a typo(i think).

I believe the OP meant that an 11/64" drill bit is needed....NOT an 11/32"bit. 11/32" would make much too large a hole for a 1/8" pipe tap.

Am I correct or am I not thinking clearly?

 

[cyclops2]

Re: Proper tell tale location for my Johnson V-4

Ok
I went to the Machinist Handbook.

21/64" = .3281" too small

.........= .3320" ....= Q.....Perfect size

11/32"= .3438........Way to big. I will go down & check my 1/8" NPT tap.....It is gone. I will check some tables & report back
Use some kind of lubricant on Aluminum.....OIL ONLY .....Some steel types WILL eat Aluminum.....Plain oil is always safe.

Do you have enough space inside the water jacket ? You may be forced to use a BOTTOM tap for all the threads. Carefull.

Be back

 

[cyclops2]

Re: Proper tell tale location for my Johnson V-4

Lots of Q size only.

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

What is "Q size"? I stopped into Home Depot and they sold 1/8th taps bundled with the corresponding drill bit, but I didn't pay attention to what the drill bit size was.

I ended up getting a small tap set from Harborfreight.

There is plenty of room inside the water jacket from what I remember(when I replaced head gaskets this past summer). The sticky also shows plenty of room inside the jacket.

I've googled and see the 11/32" drill bit size may be correct, so maybe I have no idea what I'm doing.

 

[boobie]

Re: Proper tell tale location for my Johnson V-4

Not to be a smart ***** but you are dealing with pipe threads which are tapered.

 

[cyclops2]

Re: Proper tell tale location for my Johnson V-4

Bonarill

This tapered threading DOES REQUIRE a lot of practice to do right. You CAN NOT make a mistake doing any part of the drill sizing, drilling, taping depth.

I recommend you have someone who does doing NPT threading for a living do it. Machine shop or a marine shop who is experienced in Aluminum NPT.

If you have bad luck. It is hopefully a Aluminum welding job that is sucessfull.

NPT is a HIGH RISK job.

I would also see if you can find a ....Aluminum nipple....It might be safer & easier to drill a hole & weld a nipple on.

Anybody else have a thought

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

Bonarill

This tapered threading DOES REQUIRE a lot of practice to do right. You CAN NOT make a mistake doing any part of the drill sizing, drilling, taping depth.

I recommend you have someone who does doing NPT threading for a living do it. Machine shop or a marine shop who is experienced in Aluminum NPT.

If you have bad luck. It is hopefully a Aluminum welding job that is sucessfull.

NPT is a HIGH RISK job.

I would also see if you can find a ....Aluminum nipple....It might be safer & easier to drill a hole & weld a nipple on.

Anybody else have a thought

Unless I'm really missing something here....tapping a hole doesn't seem too overly complicated. According to what I've read(and seen on youtube), it's just a matter of drilling the correct size hole and making sure the tap goes in straight.

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

Parts arriving today....what do I use on the threads of the elbow to assure there are no leaks. Teflon tape?

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

Lots of views of this thread, but not many replies.


Update:
Parts arrived and this is the hose I got (I used the part#321887 from the sticky). Obviously it is WAY to short. Hose was $8 so I assumed that it was a decent length of hose. Length wasn't mentioned on marineengine's website.

Can I just use 1/4"ID fuel line as the tell tale hose. I can find that an any auto parts store.

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

Update:

I was a bit nervous about drilling a hole in my motor, but I was able to drill/tap it without any problems. 3 revolutions of teflon tape on the threads and screwed the elbow in. Seems nice and snug, but I won't be able to check for leaks until I start the motor for the season.

Anyone know if 1/4" ID fuel hose is ok to use for the telltale?

 

[boobie]

Re: Proper tell tale location for my Johnson V-4

If the hose will handle fuel, water should be no prob.

 

[BonairII]

Re: Proper tell tale location for my Johnson V-4

The only reason I asked was that I wasn't sure how fuel line would hold up against hot water over time.

 

[RoughFishAssassins]

Re: Proper tell tale location for my Johnson V-4

Bonairll, What location did you eventually choose, I am in the process of ding this also and am undecided as to where I should put it, I'm not sure if I want to ust the cast-in boss or if I want to go on the top of the block behind the coil bracket, or if I want to go on the otherside of the coil bracket. Top of the motor I think would be the best soit pushes all the air out of the motor, but do I go on the flywheel side of the coil bracket or the otherside?? I appreciate any help you can give!

 

[archcycle]

Re: Proper tell tale location for my Johnson V-4

The only reason I asked was that I wasn't sure how fuel line would hold up against hot water over time.

I wouldn't put teflon tape on something that has the potential to get really hot. It'll probably be fine but you should think about removing the teflon tape, screwing the elbow back in, roughing the elbow and the surface up with sandpaper and then putting a small ring of JB Weld or Water Weld around it.