Max power at what Revs?

[Nasher]

Hi all

Can anyone confirm at what revs my old Johnson 150VRO should make max power.

I've only been able to get hold of a manual for a later 60Deg vee 150 and that makes max power at 5000 RPM.

I think 5K RPM is right for my old engine too, but wondered if anyone knows for sure.

Cheers

Nasher.

[RIB BOI]

i reli dont no if this helps.

but i had a 140hp evn that did 5.5k to 6k revs it was a 1994 140 evenrude.


Josh

[TIM]

Go on to www.boatsetup.com and in the Evinrude fourm , there is a few guys on that who will tell you anything you want to know about any Evinrude ever build ..... and if you give them the engine no, they could proably tell you who assembled it !!!!!

[Nasher]

Tim

Hi, I've posted the same question there.

Josh

Thanks for that, perhaps I can get some more revs out of it.

Whilst I think about it, does anyone know how many pole alternator the engine has.
I thought it was 12 pole, but when I connected up the mercury tacho I got hold of, I had to switch it to the 4 cylinder position to get it to read anywhere near right.

Nasher

[Wile E Coyote]

Nasher, if you can give me the model number of your motor, I should be able to answer all your questions as long as when you say "old" 140 it's not later than a 1991 model. I have the manuals for all 'Rudes and Johnsons up till 1991.

[Alan]

Nasher, when I had a 150 GT VRO I think it rev'd to 5500 at least. 5k sounds too low, perhaps you are overpropped?

[jwalker]

Nasher, if it's a standard 150 it max's out at 5000rpm (155hp). If it's a 150GT it max's at 5250rpm (175hp)

[Nasher]

Thanks Guys, its a GT VRO 150 and its only reving to 5000 RPM with a 17inch prop which everyone is telling me is too small anyway.
Tried a 21inch which held it back to 4000RPM

Need to go away and think about this one.

Nasher

[Alan]

Nasher, my memory is fading these days but I think we ran a 17inch pitch prop on our GT150 on the Deep Sea 21. I seem to recall we couldnt spin a 19 at full revs. I know we played around with props to try and maximise fuel efficiency and then came to the conclusion that it made b*gger all difference as the blimmin thing drank gallons of unleaded whatever we did

[Nasher]

Alan

Hi, it certainly does drink petrol.

I've been trying to keep it going on the cheap whilst also atempting to replace it with a new tech 2-stroke at a bargin price, more of that another time.

Didn't realise my GT150 was actually a 175HP, makes the performance even more dissapointing.

Nasher