limited max rev during breaking in?

[berrax]

Hi
I have got an almost new (~10 hours) DF15A. The topspeed with my dinghy is 19 knots. At this speed I use perhaps 60% of the power. After that, the red lamp is lit and the engine can not rev any higher. I doubt that it is 6000rpm which is supposed to be an acceptable maxrev.

If I reduce power just a little bit when the lamp is lit, the lamp goes off and the engine is again running smooth.

Is there any function during breaking in that reduces maxrev?

Regards
berrax

[Moonlighter]

Not a aware of any rev limiter that applies during running in.

Check your owners manual, though, it may give you more info about that, as well as about the warning light.

You really need to know what rpm you're getting at wide open throttle. There are after-market tacho's like the "tiny tach" that are inexpensive and might be worth you getting because it does sound possible that you're hitting the limiter. Google and you will find.

Does it kind of break down the spark at full throttle when the light comes on? That is what the rev limiter does.

If that's the case Perhaps talk to your dealer about possibly going up a couple of sizes in pitch and test again. If you get more speed and no red light/breaking down then you've found the answer.

[Moonlighter]

What the.......

I posted reply but got some weird message about it having to be edited by a moderator!

Anyway, there's no rev limiter that specifically applies during running in. But check your owners manual to be sure.

It sounds like you're under-propped. Try to find out what rpm you're hitting. A cheap "tiny tach" will do the job. Or, you can just try a alternativ prop with 2-4" more pitch to see if you get more speed and no red light or rev limiter.

[Harper]

What the.......

I posted reply but got some weird message about it having to be edited by a moderator!

Heh-heh..... you musta used too many three, five, six, and eight letter words....

[berrax]

Hi,
I have checked the manual and it says nothing about limiting rev during breaking in...... it was more a hope from my side....

But what makes me confused is that the manuals says that when "overreving", the system is reset by going back to idle for one second. In my case it is not like that, I just reduce the power a little bit.

You might be right about that the propeller is to small. I will by a tach to measure it. The engine is running real nice, I might be fooled by the soft running and underestimating the rev...

For me it might be the wrong thing to go to a bigger prop - When the boat is fully loaded I need a lot of power at low speeds to "get started".

[Moonlighter]

Fair enough. Understand about props. On small boats like that props are pretty cheap so many people have 2, one for light and one for heavy loads.

The other option is to get your dealer to connect it up to the Suzuki diagnostic software and see what codes it has recorded. Those red lights you've been getting will most likely have created a record in the system that will tell them what's been happening. It's a new motor so sensible to play safe with it, just in case it's another problem that needs some attention.

[berrax]

I will now be away four weeks and probably use the the dinghy almost every day. If I after that dont understand the situation, the its time to hand it over to a workshop for to analyse it.

Buest guess today is then perhaps tham I am "overreving" it.

Thanks for answering.

[berrax]

Now I hav tested with a tachometer, and the engine cuts at 6200 rpm.

I suppose that is what could be expected.

But I was surprised that the engine was running so softly at that speed!!!

[Moonlighter]

Yes, they are surprisingly quiet and smooth at revs!

Well now you know the issue.

I think that if you are easily hitting the limiter then you could go up a couple of inches in pitch and still get great hole shot.

[berrax]

I wil try during the summer and then maybe upgrade to next year.

It would be fun to get some more knots in topspeed...