85/86 Evnirude 30 hp need a tach?

[darrklim2]

What kind of tachometer would I need for this motor. Will an automotive tach work or does it have to be a marine tach? I am trying to find out my rpms to find out what pitch of prop I need. Right now at Full Throttle it sounds like it is running really high rpms just from the sound. Can anyone tell me the recommended rpm's for this engine at Full Throttle. Thanks
Model is 30TELCOA

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

It is an 85 not an 86. I wasn't sure before but I know that now.

 

[F_R]

Re: 85/86 Evnirude 30 hp need a tach?

A car tach won't work. You need a alternator tach. I am pretty sure yours takes a 10 pole (5 pulse) tach. Marine dealers will know what that means if they have any smarts.

Your motor is 25hp @ 4500 rpm. Full throttle operating range is 4000-5000 rpm. Aim for 5000 with one person in boat.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

ok, thanks, I am sure it sounds higher rpm's than 5000 but I don't know for sure. my prop says 10 x 13 that is 10 inch and 13 pitch am I correct.

 

[offshore100]

Re: 85/86 Evnirude 30 hp need a tach?

Just checked the manual; 30hp @ 4500-5500 rpms.
Have a 10 x 15 on mine, driving an 18 foot doublewide jon boat. Is your boat light or heavy? Believe you should go up in pitch, unless you carry heavy loads.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

my setup weights roughly 1000 pounds - Boat, motor, gear, me and one other passenger. It is a 1969 lund/shell lake 15' long and 5' wide fiberglass tri-hull. Any more info needed just let me know.

 

[offshore100]

Re: 85/86 Evnirude 30 hp need a tach?

I'd go up in pitch if I were you. And you'll likely get a higher top end speed in the bargain.
Like I say, my jonboat with this motor is 18', and I'll often carry five others aboard; 10x15 works a treat. They're even available in 10x17, but that may be too much.

 

[F_R]

Re: 85/86 Evnirude 30 hp need a tach?

My 35hp cousin to your 30 turns 6000 RPM with a 17" cupped SST on a Lund 14" Aluminum. But I'd say it would be too much for your 30 on a 15' Figerglass.

 

[F_R]

Re: 85/86 Evnirude 30 hp need a tach?

Wondering where I went wrong with prior specs of 25 hp, I went back and looked again. That was for a '85. The '86 30hp is rated at 5500 RPM, full throttle operating range is 5200-5800. Reference: 1986 Evinrude Sales Brochure Specifications.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

Should I go up one pitch or two?

You say you have a 15 I have a 13 right now?

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

what kind of rpm's do you run with your 15 pitch on your 18 jon?

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

What if I went to a 4 blade 14 pitch what difference would that make? Does anyone know?

 

[offshore100]

Re: 85/86 Evnirude 30 hp need a tach?

what kind of rpm's do you run with your 15 pitch on your 18 jon?

well, it's an '85 model on the 18', and sounds good to me, and has lasted this long lol, I reckon all's well. Never put a tach to 'er.

Four blade 14" prop, hmmm, heaps more drive and pulling power I'd guess, and prbably heaps more expensive.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

well, it's an '85 model on the 18', and sounds good to me, and has lasted this long lol, I reckon all's well. Never put a tach to 'er.

Four blade 14" prop, hmmm, heaps more drive and pulling power I'd guess, and prbably heaps more expensive.

The only reason I asked about the 4 blade is because there is one on ebay. Thought maybe if that would work and went for cheap enough it might be worth it.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

offshore-

How well does this motor work for you.
Could you tell me how wide your jon is at the transom. I am actually looking to get a Rogue 1886 next year and I was going to keep this motor and put it on the new boat. The Rogue is 18 feet 7 inches long and 85 inches wide at the transum.
The link is below.

http://www.monarkmarine.com/?page=seriesdetails&hullid=4&serid=38&tab=modeldetails&boatid=674&section=specs

 

[offshore100]

Re: 85/86 Evnirude 30 hp need a tach?

Hi darrky (that doesn't sound quite right),
Nice looking boat, I don't think you'd have any trouble with your motor on it. And I'd guess with you and one other aboard she'd probably make 25-30mph. My thirty works great on the 18 foot double wide. Not sure how wide but, wide.....bugger if I'm going out and measure it.
Personally, I don't need to go super fast, and I like things simple and dependable.

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

thanks I am not too worried about speed either my main thing is that it can get on plane and run efficiently

 

[darrklim2]

Re: 85/86 Evnirude 30 hp need a tach?

Alright I got a tach today but I don't know which wires to hook it up to on the motor? I have heard somewhere on here about a gray wire but I don't see a gray wire anywhere on my motor.

I have two threads going right now that have led to the same point from different starting positions. I don't know which one to continue with.

the other one is called 3 blade vs 4 blade

 

[offshore100]

Re: 85/86 Evnirude 30 hp need a tach?

Unless I'm sadly mistaken, our motors don't have grey wires. Mine certainly doesn't, it doesn't have an alternator. It's rope start. simple is good....

 

[caper_45ca]

Re: 85/86 Evnirude 30 hp need a tach?

I have a 95 rude that is rope start also and thye only tach that I could get that worked well is one from tiny tach. It works by wrapping a wire around one of the spark plugs...great 4 me......try this site

http://tinytach.com/tinytach/index.php