Aux engine

[Poly]

Originally Posted by beamishken

Id have thought an old school 2 stroke like that would be ideal for infrequent use. Far less likely to suffer running problems due to carb issues from little use and easier to fix if it does.
Never seen a oil injection at that size but carrying a dedicated fuel supply isnt a bad idea if fuel contamination is the issue with the main
That yam is very light for a 2 cyl 8 and a gutsy little engine
I'd have that over a 4 stroke any day for an aux
4 stroke carbs are far more complex and therefore more prone to fuel issues. For the purpose simple is best Imho

I was always lead to believe that premix fuel had a short shelf life - not idea for something sitting largely unused. I was also taught that it was very important to run premix carbs dry to stop them gumming up. If you start the aux every time to check it is working - you are going to have to run it for about 10 mins to clear the carbs out after each day. Less of an issue if it is getting used on a tender too.

Originally Posted by paulb33

I’m curious about an electric Torqeedo that can serve both the tender and RIB. That helps with weight and fuel issues. Putting cost issue aside (for now) what are views? https://www.electricoutboards.eu/cru...ts-c2x22282972

Search forum for Torqueedo. John Kennett had one. He didn't keep it long. That may answer your question about using one on a tender. The only purpose I can see it serve as an aux, is a comfort blanket for the missus so she thinks you have one!

[beamishken]

Originally Posted by Poly

I was always lead to believe that premix fuel had a short shelf life - not idea for something sitting largely unused. I was also taught that it was very important to run premix carbs dry to stop them gumming up. If you start the aux every time to check it is working - you are going to have to run it for about 10 mins to clear the carbs out after each day. Less of an issue if it is getting used on a tender too.

Its even more important to drain the carb of a 4 stroke especialy with modern fuels or it gums up the tiny orifices in the carbs
So if its harmfull for a 2 stroke its even more so for a 4 stroke

A few ltrs of pre mixed fuel in the main tank wont hurt even an injected engine
Alternatively the oil could be stored in measured doses to be added as required when needed

[Nos4r2]

Originally Posted by Last Tango

You could.....but it might smoke a bit.

I was wondering about it fouling sensors.
At 100:1, the 2 strokes barely smoke. Mixed at 1000:1, you wouldn't even notice it coming out of the exhaust of a 4 stroke.

[paulb33]

The only purpose I can see it serve as an aux, is a comfort blanket for the missus so she thinks you have one!

[emoji23]

[Pikey Dave]

Originally Posted by GuyC

Looking at it slightly differently.

I have a 3.4m Zodiac SIB that I'm planning on using as a tender for my RIB. It has a 15HP Mariner engine which will also double up as an aux engine should I need it.

The Torqueedo (electric) motor would be an interesting option. A quick look on line suggests they do a 8HP version which might be enough for what you need. It's pretty expensive but relative to the boat and the kids, probably not too bad. I'm sure it could be kept charged via the main engine and it's half the weight o an equivalent petrol engine.

8hp@12V = 500A [emoji15][emoji15][emoji15][emoji15]bring on the Duracell bunny[emoji6]

Ps just checked, it runs at 48v but that's still 125A or thereabouts & the battery weighs 50kg min[emoji15], & whats (no pun intended) "more power per Watt" all about. Watts are a measure of power, a Watt is a Watt. "Ye canna change the laws o'physics Jim"