Which 4hp 4-stroke outboard?

RobW

RobW

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Hi folks,
At the start of the season I find myself in the rather fortunate position of being able to go out and buy a nice new shiny outboard for our 20ft copland harrier trailer sailer.

There was nothing much wrong with our old outboard - a faithful old Mariner/Yamaha longshaft 5HP 2 stroke dating back to the early 1990s. It was starting to show its age a bit, but will go on for a few years to come I am sure (now sold).

The order to replace it came from an unexpected source - the wife! A bit of a green, tree hugging type - she saw the colour of the water in the wheelie bin as I was running/flushing the engine out at the end of last season. After her initial horror and a bit of a rant about what we were pumping into the sea, I was told to get a 4 stroke! So, who am I to argue!

Now for the bit I am stuck at - which one!!!!

I have decided that 4HP is probably enough following a trial with a friends motor at the end of last season - the boat is lite and easily driven.

It must be:
longshaft
Have F-N-R gears
An external tank and charging circuit are desirable, but not essential.

From looking at websites, I have gathered the following info.....
Suzuki and Johnson outboards are exactly the same.
Mariner and Mercury are exactly the same, and tohatsu has the same powerhead.

I was initially tempted by the Mariner/Mercury 4MLH/4 sail version which offers charging and a special prop, however two dealers who sell them said things that made me question build quality? Has anyone got any experience of this motor?

I was also very tempted by the Yamaha F4 Longshaft. Its a couple of KGs lighter than any of the others which is great, it also has the connection for an external tank, but no charging possibility and I am told it is considerably less powerful than other 4hp motors, particularly when compared to the Johnson / Suzuki? 112cc v 138cc. Does anyone have any experience of using this motor on a similar boat? Is it powerful enough?

I have no experience of the Johnson/ Suzuki so interested to hear from owners?

Over to you - what would you buy?

With thanks

Rob
 
nice to see someone willing to back up their principles with their cheque book. /forums/images/graemlins/cool.gif

We have used a 2003 Suzuki 4stroke DF 4 for 2 seasons now .This is exactly the same as the Suzuki DF 6 but with a throttle stop fitted to reduce the revs.

It has been reliable except one occasion last year when it stopped due to overheating. i stripped down the powerhead off the drive leg to clean out the waterways but it turned out to have been unneccesary,the blockage had cleared itself.

It is fairly heavy to carry at about 25 kg but not much different to other makes it has a good carrying handle.It has a charging coil to top up the battery.We use the built in tank but you can use a seperate tank. It has FNR gears

The Suzuki 4 hp pushes our Anderson 22 at about 5 knots It has plenty of thrust in forward and reverse for manouvering onto pontoons etc. The 1.5 liter built in tank runs for over an hour.

personally I dont think theres much difference in the different makes.See what deals you can get on the price.
Cockpit.jpg
 
I have a Mercury 5 hp (same motor as 4 with smaller carb) on my Parker 21 with "sailing" prop. Works very well and once pushed us all the way back from Cherbourg on 12 litres (15 hours!). But, having only one bang every other rev, it does vibrate more and make more noise than the Mariner 5 2-stroke it replaced.
 
I've had problems with my Suzuki 6hp (similar design to their 4h). Mine was delivered in April 2005 and have had fuel problems, rough running. At the annual service last year bad corrosion problems were found. It is still with the dealer for this year's service will try to remember to update this thread when I know how it went.
 
Sorry to hear your problems.We are luckier than most in that we lock into a freshwater bay to get to our mooring so the motor gets a good flush with fresh water everytime we come back to the mooring.

What was corroded on yours?
 
Merit, my Copland Foxcub, came with a 3 year old Mercury 4hp, which I was quite pleased about, however we have had problems. Firstly we discovered that the rotation locking key has lost it's thread and now the spring which hold the pitch bar is slipping which means that it could, in theory, pop up if I go into reverse too hard.

I have tried to get in touch with Mercury about replacement partys but thus far, my emails have not received the courtessy of a reply. (Any Mercury reps on here, feel free to PM me).
 
As far as the Tohatsu range goes, I dont think there is a 4 with all the bits you need as standard - to make one up with an external tank option and charging loop it would be 850.00. For that same money you could get a Saildrive 5HP.

The basic 4HP four-stroke with internal tank is 680.00, by the way.
 
I have the Yam 4 and it's a cracking motor. Smoother and quieter than the Honda 5 I had before. Plenty of grunt for my Foxcub. I never have to use full power.
I adapted the gearchange with this extended handle (just two bolts through the small plastic stub lever) and it transformed the gearchange, very positive now.

Outboardgearlever2.jpg
 
We had rusted exhaust, but some screws fell off the internal tank mounts and it has never run well. Went back to the original dealer twice and they said it's normal. Reminds me of the first low emission cars of the early 1980s - they adapted the old designs with loads of modifications and they were terrible until new designs came along. Is this what has happened with four stroke outboards (of just Suzukis)?
 
I have heard other people say about corrosion on Suzukis but have to say when I stripped ours down last year it was all pretty much as new. The motor has been kept on the boat for 2 years but possibly the previous owner kept it ashore which may have helped preserve it.



I do the servicing myself which basically is just top and bottom oil change plug change little bit of grease here and there and wipe over with oily rag.

Im quite dissapointed to hear about your probs only time will tell if its a general prob or specific to one batch of motors perhaps.
 
Bought a Mercury single cyl 4 stroke albeit 6hp but v. similar to 4 hp. Noise and vibration became such an issue that it had to go. Bought yamaha - cost plenty - would spend it again tomorrow though. Beautifully smooth and never, ever an problem to start or run.
 
Hi Lemain

What a bummer. I have a 6hp DF Suzuki too but she has been 100% reliable since I bought her 3 years ago.

I don't bother with a dealer service but change the oil and plugs and grease the nipples and linkeages myself. I do flush her out after each use which has probably stopped any corrosion problems and am delighted with the performance. I think its a smashing engine but would be very interested knowing what the problem is once your dealer has serviced your engine.
 
/forums/images/graemlins/confused.gif Do you use it as your stern anchor as well??Just wonderd why the heavy garden chains attached? Or dose it risk falling off the bracket?

Looks good though! From all this im not sure 4 stroke is more economic than 2 stroke?

My 1986 Evinrude runs smoothy quitly? and starts first time. Id be very sorry if i had to find £900+ to change, i hope i can go on useing mine for years to come.

The thought of haveing to drop my beloved reliable O/B overboard in the interest of ecologly is illogical as 2 strokes last longer dont need oil changes, use less fule per HP so a smaller lighter less thirst 2 stroke can be used if chosen carfully.

In eco contries ive seen very small boats with 45 hp 4 strokes when in France would have 25 hp 2 strokes. /forums/images/graemlins/cool.gif

While on the eco subject: Why, when its so walm and sunny everyday like an English Summer, are the nights like Swedish summers freezing! I think the nights are colder this year than last even when the days were a cooler last year??

When its walm everday, why cant the nights be a bit(lot)walmer???When i stay out it costs a fortune to heat!Ive paid for a place untill April but when the weathers so glorius you cant stay put just becouse the power for the fan heaters included!!
 
The chain serves a dual purpose.
One, to discourage scrotes from pinching it and
Two, to, as you suggest, secure it from the 200 ft plunge to oblivion.
 
[ QUOTE ]

We have used a 2003 Suzuki 4stroke DF 4 for 2 seasons now .This is exactly the same as the Suzuki DF 6 but with a throttle stop fitted to reduce the revs.


[/ QUOTE ]

Thanks for your post and excellent photo.
But just for info, is the throttle stop the only difference between the Suzi 4hp, 5hp and 6hp four-strokes? Are there no other differences: eg restrictors in the intake, different jets, gear ratios, prop pitch, etc? Just wondering.
Best wishes
 
[ QUOTE ]
eg restrictors in the intake, different jets, gear ratios, prop pitch, etc?

[/ QUOTE ]

im not 100% sure about all the above. On the Suzuki website there is a chart showing all the details of the different engines and the 4,5and 6 have identical engine size ,ratio and props only the revs are different.

.I dont think there is a restriction on the intake (but Im not positive).i have been told that by ordering the throttle stop for a 6 and swapping it for the one on my carb the revs go up and it becomes a 6.I wont be doing it though as I dont need the extra power and I like the idea of it being governed down a bit.

If you need a 6 it would seem you could save a couple of 100 pounds by getting the 4 then changing the throttle stop arm.

Suzuki Spec page
 
[ QUOTE ]

If you need a 6 it would seem you could save a couple of 100 pounds by getting the 4 then changing the throttle stop arm.


[/ QUOTE ]
Thanks for the reply. And that's quite a saving just for a throttle stop! Seems amazing...
Best wishes
 
I dont know how they can justify it.I just looked at the Suzuki price list the difference is nearer £300 .

DF4s is £625 The DF6s is £919.

The throttle stop is a bent piece of stainless about an inch long with one screw holding it on. If you new the exact length required you could make one in 20 minutes. /forums/images/graemlins/confused.gif
 
I bought the Mercury 4hp 4 stroke last year - very impressed, quiet, very reliable and seemed well made. Only issue I had was it had less of a range of settings for latching up in shallow water than my old engine. Other than than - fantastic bit of kit...
 
Hi, thanks for your reply - I am very tempted by the Yam 4hp 4 stroke longshaft, previous experience of Yam build quality has been very good - it does however have less CC than other 4hp models - do you think it would have enough grunt to push along the Harrier 20?

Cheers

Rob
 
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