Rev Limiter?

[doktrred]

Should my 1998 150 VMAX (2 stroke), have a rev limiter and IF so, what is it typically set at?

[boscoe99]

Yes.

6150

[doktrred]

Thanks,
While testing a new prop, I got 39 mph @6300 rpm at WOT and Marcus at Power Tech said the motor shouldn't have gotten that high and mentioned a rev limiter.

What component sends input to the CDI to control high rpm's?
Is there a way to troubleshoot this?
I looked in a service manual I have and there wasn't even a mention of a rev limit circuit, unless I missed it.
I've found posts on line where some folks disable this system, don't know a lot about this motors's history.

BTW, your posts on low oil warning and oil transfer, helped me solve my low oil warning.limp mode issue.
Mike

[99yam40]

I would check the accuracy of the tach just to be sure it is correct.

but then you do no plan on using that prop, do you?

[boscoe99]

Thanks,
While testing a new prop, I got 39 mph @6300 rpm at WOT and Marcus at Power Tech said the motor shouldn't have gotten that high and mentioned a rev limiter.

What component sends input to the CDI to control high rpm's?
Is there a way to troubleshoot this?
I looked in a service manual I have and there wasn't even a mention of a rev limit circuit, unless I missed it.
I've found posts on line where some folks disable this system, don't know a lot about this motors's history.

BTW, your posts on low oil warning and oil transfer, helped me solve my low oil warning.limp mode issue.
Mike

In your model the crank shaft position sensor (a component of the stator assembly) sends an AC voltage input to the CDI. The CDI transmits that input to the tachometer.

The tachometer is more than likely the problem. Is it digital or analog?

If you are crafty and you have a spare surplus wall wart available (120 AC volt to 12 volt DC converter) you can use it to test your tachometer.

Glad to hear you got your oil problem fixed.

[boscoe99]

Oh, if the red line on your model is 5500 RPM, why are you over speeding the motor?

[doktrred]

The tach is analog.

<<why are you over speeding the motor?>>

Being new to owning a boat , trying to find a prop for this boat, since I found a crack in the case of the TRP that the boat originally had on it. Were to told run the boat to WOT and note rpm's and mph, and what kind of a hole shot it had. Motor wasn't over 6000 but for a few seconds, on two different runs.

I MIGHT be able to find a wall transformer, would love to know how to check the tach.

As far as the prop, right now I don't know what I'm gonna do, not sure why we're getting similar numbers on 2 different models and different pitch props. I'll create another post on this once I try and find out if this tach is accurate or not. And if it is accurate, why didn't the rev limiter kick in.

[panasonic]

You can get a little tach on amazon for about $30...I have one and its pretty accurate. I put it on several engines and it read the same a the factory boat tachs. It also compares good to my tach on my timing light.

You could put it on your engine to check out your tach

This is not the exact one...but similar.

https://www.amazon.com/Searon-Digita...re-bullets-btf
.

[99yam40]

I MIGHT be able to find a wall transformer, would love to know how to check the tach.

I have not tried it, so maybe Boscoe will chime in on what it should read when hooked up to a 12Vdc wall charger.

I am guessing that since the tach counts pulses it would read the 60 Hz pulse.
common sense says what it would read out is 3600RPM.
60Hz X 60 seconds/min = 3600

[doktrred]

I'll see if I can find one of the tach's you mentioned, I THINK I have a old tach I used on my 69 Camaro years ago, not sure if that would work or not?

I couldn't access this site for about 48 hours, seems when I tried to get here some virus or worm or something tried to redirect me, not sure if it was on my end or not?
Still would love to hear the specifics on testing with the wall charger, but not in a big hurry

Thanks again for the help

[99yam40]

we all had that problem too