4-6hp 4strokes

gjgm

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The tanks seem to be about a litre..any one give me a clue how long that lasts on a four stroke... 30 mins, and hour, a week !
And what sort of difference would there be between 4+6 hp..negligible of 30 pct or ...
Some block,same weight..just wondering why get the lower output (price, maybe)
 
The tanks seem to be about a litre..any one give me a clue how long that lasts on a four stroke... 30 mins, and hour, a week !
And what sort of difference would there be between 4+6 hp..negligible of 30 pct or ...
Some block,same weight..just wondering why get the lower output (price, maybe)

4-5-6HP Mercury, Marina and Tohatsu are the same engines. Different coat of paint for each make/model and a different carb for each HP. So, they all weight the same. Had a Suzuki with the tiny tank and wasn't happy with how long it lasted. Had a Merc or Mariner (forget which now, but think it was a Mariner) with the separate tank and that lasted ages. Just sold a Mercury, that had the small tank and a fitting for the external tank, so best of both Worlds.
 
The tanks seem to be about a litre..any one give me a clue how long that lasts on a four stroke... 30 mins, and hour, a week !
And what sort of difference would there be between 4+6 hp..negligible of 30 pct or ...
Some block,same weight..just wondering why get the lower output (price, maybe)

This will depend on your duty cycle, WOT or puttering?
 
This will depend on your duty cycle, WOT or puttering?
Well, yes obviously !!
I just wondered if someone who had one could tell me if a litre lasts an hour or couple of hours or 3 hours...
I have a 3.5 2 st, and you cant get very far on the internal tank...so just how much more fuel efficient is a 4 stroke... or, how useful is the external tank connection option, in reality, on a small o/board. Is it something to go for...?
 
Hi Gavin

I have a 3.3 2 stroke with an internal tank and a 6hp four with an internal tank. The little two stroke I think goes through fuel quicker than the 6hp. The thing is it really depends if you pootle in your tender or if you get it upon the plane, or even worse, plough it through the water just off the plane. Proper pootling will see an internal tank last quite a while, maybe a few hours, ploughing or planing may give you under an hour. Very difficlt to be precise, but I have never felt the need to use an exyternal tank on a small outboard and I like to explore in my dinghy as much as possible. I have taken a spare 5 litres with me but I can't actually think of a single time I have needed to top up with it before returning to the boat.
 
Hi Gavin

I have a 3.3 2 stroke with an internal tank and a 6hp four with an internal tank. The little two stroke I think goes through fuel quicker than the 6hp. The thing is it really depends if you pootle in your tender or if you get it upon the plane, or even worse, plough it through the water just off the plane. Proper pootling will see an internal tank last quite a while, maybe a few hours, ploughing or planing may give you under an hour. Very difficlt to be precise, but I have never felt the need to use an exyternal tank on a small outboard and I like to explore in my dinghy as much as possible. I have taken a spare 5 litres with me but I can't actually think of a single time I have needed to top up with it before returning to the boat.

We have a Suzuki DF6 and as neale states it does have both internal and external tank capability, we just use the internal tank and the furthest we tend to go in our dinghy is from Bucklers Hard up to Beaulieu Village and back...or up the Yar to Freshwater so probably a 40 minute trip in total and it does that on circa 1/2 tank from memory so I reckon 1hr 30mins probably would be about the max at 1/2 to 3/4 throttle with a dinghy weight of around 35kg with 2 adults & 1 child.

Our Honda 2hp (watercooled 4st) has a smaller internal tank and probably runs for around 1hr before re-fill with similar throttle and pushing same weight..

....But we always take a spare can of fuel if adventuring far!.... (and a couple of kit-kats if things really get rough...)
 
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We have a Suzuki DF6 and as neale states it does have both internal and external tank capability, we just use the internal tank and the furthest we tend to go in our dinghy is from Bucklers Hard up to Beaulieu Village and back...or up the Yar to Freshwater so probably a 40 minute trip in total and it does that on circa 1/2 tank from memory so I reckon 1hr 30mins probably would be about the max at 1/2 to 3/4 throttle with a dinghy weight of around 35kg with 2 adults & 1 child.

Our Honda 2hp (watercooled 4st) has a smaller internal tank and probably runs for around 1hr before re-fill with similar throttle and pushing same weight..

....But we always take a spare can of fuel if adventuring far!.... (and a couple of kit-kats if things really get rough...)
OK thanks.
I think the only time I wondered was use on the Dart when I relaised the guzzling two stroke wouldnt get up river very far. As I am thinking of another small purchase, I was just wondering about which engine. By the sound of it, a four stroke and a 5 litre spare is likely to be enough for most eventualities.
I only use the two stroke on the tender, and I doubt I get through much more than 5 litres a year. The next venture might be used somewhat more though.
 
OK thanks.
I think the only time I wondered was use on the Dart when I relaised the guzzling two stroke wouldnt get up river very far. As I am thinking of another small purchase, I was just wondering about which engine. By the sound of it, a four stroke and a 5 litre spare is likely to be enough for most eventualities.
I only use the two stroke on the tender, and I doubt I get through much more than 5 litres a year. The next venture might be used somewhat more though.

Gavin, if you happen to be considering a Suzuki DF6, FWIW ours been very reliable, one thing to consider when buying a 6hp is whether to go single cylinder or two cylinder, Suzuki and Mercury & I assume Mariner are single and therefore lighter (circa 25kg's) than the smoother in performance twin cylinder Yamaha but the weight of the Yami is 37kg.... now that is a weight! . TBH I struggle sometimes with our DF6.... and unless you have bulked up since I last saw you that may be something worth thinking about before you buy.
 
Gavin, if you happen to be considering a Suzuki DF6, FWIW ours been very reliable, one thing to consider when buying a 6hp is whether to go single cylinder or two cylinder, Suzuki and Mercury & I assume Mariner are single and therefore lighter (circa 25kg's) than the smoother in performance twin cylinder Yamaha but the weight of the Yami is 37kg.... now that is a weight! . TBH I struggle sometimes with our DF6.... and unless you have bulked up since I last saw you that may be something worth thinking about before you buy.
I have bulked up, but I think that was Xmas ...
I just think 3.5 might be a bit too feeble.
I'll give it to the wife to carry, so I wont have a problem with it ;)
 
If you go with one that has the integral tank and the fitting for the external tank, you could use the integral tank for short tendering and an external one for longer trips (we sometimes used our tender for Mackerel fishing, for instance, where we were out for a while).

That said, i never really felt safe with the integral tank, except for the shortest of trips, unless i was carrying a 5lt can. I figured if i had to carry a 5lt can most of the time, i might as well use the external tank.
 
when I looked at 4 6 8 10 outboards I came to the conclusion I may as well have a 10 with a separate tank.

I managed to get a 9.8 2T outboard that was the same weight as a 4hp with a full tank of petrol.

A separate 10L petrol tank and decent outboard solves the problem of carrying a light outboard full of petrol which is just as heavy anyway.

Just a thought, you have a nice boat, seams a shame to spoil the enjoyment with an underpowered tender .
 
when I looked at 4 6 8 10 outboards I came to the conclusion I may as well have a 10 with a separate tank.

I managed to get a 9.8 2T outboard that was the same weight as a 4hp with a full tank of petrol.

A separate 10L petrol tank and decent outboard solves the problem of carrying a light outboard full of petrol which is just as heavy anyway.

Just a thought, you have a nice boat, seams a shame to spoil the enjoyment with an underpowered tender .

With current four strokes the 4/6 is much lighter than an 8 or 10. If you need to carry it or take it on and off the 4/6 is about as big as you can comfotably go. I agree that the 9.8 2T is just about the best tender engine you can get for power:weight but they are getting very difficult to get hold of now.
 
when I looked at 4 6 8 10 outboards I came to the conclusion I may as well have a 10 with a separate tank.

I managed to get a 9.8 2T outboard that was the same weight as a 4hp with a full tank of petrol.

A separate 10L petrol tank and decent outboard solves the problem of carrying a light outboard full of petrol which is just as heavy anyway.

Just a thought, you have a nice boat, seams a shame to spoil the enjoyment with an underpowered tender .

This is for something with flappy bits....there isn't room in the well for more than a 6,but they say from 3.5 is enough
Nonsense of course...
Mind you I don't know why our tender is so slow...everyone zooms past us
on 2.5hp
 
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