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4evafishin
26-09-2005, 03:17 PM
Recently I purchased my dream boat (what I could afford anyway) a V17L the boats in very good condition -- the motor is very good nick as well -- the only thing is it seems to starve for petrol sometimes ie: surges or the revs die off -- I give more throttle and it comes good again for a while, the other problem is that it is a pig to start when its tilted all the way down in the water. If I lift the motor out of the water it will start easier. I had a service on it and cleaned the carby bowls. I'm used a motor that will start first pop every time.

Are all Jono's like this ??

If anyone has any ideas (preferably the easy things first), I dont want to start ripping it apart unless i really need to.

FNQCairns
26-09-2005, 04:07 PM
Be careful! those engines are almost bulletproof you might have blown it up by now! - if it were a more temperamental engine! when they surge like that it's best to come back in at a speed where it is running very smooth and happy, or at displacement speeds or get a tow (probably best).

Your problems are not engine brand related but maintenance and tuning/service related.

IMO find a mechanic that can service the carbs properly and checkthat the fuel system is up to the task at the same time and do a 'link and sync'.

After that has been done work on the starting if it is still a problem (it might not be).

Consider finding a mobile mechanic or an owner is the mechanic type of outboard repairers, too many dealers are parts replacement shops these days because it makes more money but the mechanics never learn how to fix/tune/diagnose well in those shops.
cheers fnq

4evafishin
26-09-2005, 05:38 PM
Thanks mate -- no I havent blown it up yet

More info

The surging ie: reduction in revs usually occurs about 20 mins into a run. I give it more throttle and it surges until I get it under control again. Then the rev reduction will continue and same senario will repeat at shorter time durations. I think getting a tow is a bit drastic.

I do not bring it out of the water to start it everytime, only when it gets hard to start probably after the fourth or fifth attempt.

Other than it goes like a rocket I am very happy the performance, I'm not 100% confident with it while it is not operating well off shore.

My outboard mechanic did the service just after I bought the boat -- he gave the same review as you about these motors. However it was his opinion (it might be wrong?) that you could not tune these motors because they were self tuning.

Thankyou for your information
Regards
Kezza



Be careful! those engines are almost bulletproof you might have blown it up by now! - if it were a more temperamental engine! when they surge like that it's best to come back in at a speed where it is running very smooth and happy, or at displacement speeds or get a tow (probably best).

Your problems are not engine brand related but maintenance and tuning/service related.

IMO find a mechanic that can service the carbs properly and checkthat the fuel system is up to the task at the same time and do a 'link and sync'.

After that has been done work on the starting if it is still a problem (it might not be).

Consider finding a mobile mechanic or an owner is the mechanic type of outboard repairers, too many dealers are parts replacement shops these days because it makes more money but the mechanics never learn how to fix/tune/diagnose well in those shops.
cheers fnq

Spaniard_King
26-09-2005, 07:28 PM
Check ta tank breathers and ya water seperator. Failing that look for a fuel leak/leaks, could be air leaking into the fule system

Garry

Brejen
26-09-2005, 07:42 PM
4everfishin. MAte for starters nice boat. I have the same with a 1990 175 Johno on the back. No problems with it TOUCH WOOD. MAte where are you at.

Brett

Pwoida
26-09-2005, 11:48 PM
Had the same motor, same or similar problem, for me it was a bad power pack. Sounds like yours is more fuel related as yourself and others have stated. If your not running the VRO, then bear in mind the fuel mixture, those engines don't like oily plugs after a long idle (from what I've been told).

FNQCairns
27-09-2005, 12:25 AM
Ok the extra info you gave makes it more of an intermittent problem, thats always a bugger. I would listen to Garry he is the real deal I am just a hack with an interest.

But I cannot help myself so here goes ;D

Tilting the engine up can do two things for certain, one is to decrease backpressure the other is to change the height of the carbie floats and the fuel in bowl level. The backpressure is a red herring because you say the engine internals are in good condition.
So it is time to go through the fuel system from tank to filter etc as Garry says then if no joy keep going until the carbs are in bits and internally spotless(replace the needle and seat and get the float height spot on [smiley=2thumbsup.gif]).

Here is why

2 stroke outboards almost never wear out 95 times out of 100, they get blown up either as a complete shock to the operator or the operator pushed it while it was playing up.
Whenever the engine is at 1/3 to 1/2 throttle onwards it is also also at maximum spark advance, every time it plays up (assuming it is leaning out etc) your engine is right on the edge of blowing up - every time!
Just be careful when you test it, come back to the ramp on the slow speed jets (displacement speeds) to be safe if no better.

I think what your mechanic meant and he is right was that the midrange and high speed jets are fixed and cannot be adjusted short of pulling them and replacing with a different size.
There is a fair bit more that can be tuned hence the link and sync I mentioned above.
Good luck with it and let us know what happens, just dont push it to the edge too many times finding out.

cheers fnq

blaze
27-09-2005, 12:47 AM
sucking air some where would be my guess
cheers
blaze

stingermuz
27-09-2005, 07:08 AM
Hi 4evafishin, just an outside possibilty - (it happened to me) - there may be something floating around in your fuel tank that's getting stuck on your strainer. I had a peice of paper (!) in mine and the result was similar to your description.

Hi Pwoida, I don't want to highjack this thread but I have an '88 Johnno 90 with the VRO disconnected and often when starting again after a run out to a spot it can take a while and it blows quite a bit of smoke. When you say "bear in mind the fuel mixture" what do you mean? Also guys, do you know why so many VROs are disconnected?

maxis
27-09-2005, 08:18 AM
had the same problem of dying of in the revs when in constant throttle for a while . push the stick down and it would respond as if nothing wrong, but would die off again after a while in constant throttle. Did nothing about it just went away by itself. Put it down to bad fuel,or maybe slighty loose fuel hoses.
Keep ya chin up yull find it, cheers

Pwoida
27-09-2005, 08:43 AM
Stingermuz,
By fuel mixture I just mean make sure you've got 50:1 caus if you've over oiled your fuel it won't hurt anything but that bit of extra oil on the plugs, particularly after a bit of trolling or sounding out a spot, will make it hard to start again. I used to give it a bit of a rev in that situation just before turning it off. Try running through a couple of litres of 60:1 then go back to a fresh tank of 50:1.

noluck
27-09-2005, 11:40 AM
i m with pwoida bad power packor your engine floding every time u lift motor the fuel cam back from caby and it is ezy to start for it i would check that 1st (chock or nidle and seal in caby change fuel filter b4 i do power pack )
cheers no_luck

bigmack
27-09-2005, 12:56 PM
Hi All - the boat we fish out of had exactly the same problem. Would surge - lose power and then come right. Sometimes on the way out to see and sometimes on the way back! We thought it was heat related after the motor warmed up a bit. Anywa - the First outboard mechanic replaced the power pack. Problem still the same. Found a mobile outboard guy to go in the boat and check it and it was the main Jet in the middle carb. Problem fixed - this is an old suzuki two stroke. As part of the process the fuel lines and filters were changed for new.

4evafishin
27-09-2005, 02:28 PM
Good on ya mate -- Thanks for the info and the advise

I'll give the fuel system a a check as you suggest, and then see how it goes.

regards
Kezza



Ok the extra info you gave makes it more of an intermittent problem, thats always a bugger. I would listen to Garry he is the real deal I am just a hack with an interest.

But I cannot help myself so here goes ;D

Tilting the engine up can do two things for certain, one is to decrease backpressure the other is to change the height of the carbie floats and the fuel in bowl level. The backpressure is a red herring because you say the engine internals are in good condition.
So it is time to go through the fuel system from tank to filter etc as Garry says then if no joy keep going until the carbs are in bits and internally spotless(replace the needle and seat and get the float height spot on [smiley=2thumbsup.gif]).

Here is why

2 stroke outboards almost never wear out 95 times out of 100, they get blown up either as a complete shock to the operator or the operator pushed it while it was playing up.
Whenever the engine is at 1/3 to 1/2 throttle onwards it is also also at maximum spark advance, every time it plays up (assuming it is leaning out etc) your engine is right on the edge of blowing up - every time!
Just be careful when you test it, come back to the ramp on the slow speed jets (displacement speeds) to be safe if no better.

I think what your mechanic meant and he is right was that the midrange and high speed jets are fixed and cannot be adjusted short of pulling them and replacing with a different size.
There is a fair bit more that can be tuned hence the link and sync I mentioned above.
Good luck with it and let us know what happens, just dont push it to the edge too many times finding out.

cheers fnq

4evafishin
27-09-2005, 04:29 PM
Fellas

I think I've solved one of the problems -- checked the fuel system over and found that one of the phillips head screws on the bottom LHS carbies bowl nearly fallen out. There was a alot of petrol in the carby cover -- guess this was the rev reduction / surging problem? I could smell raw fuel on occasion and I didnt think anything of it -- probably should of taken a look hey! I am going to go over the fuel lines and replace them -- I wont bother with looking for leaks. This is more for my own peice of mind rather the practicailty of it.

Hopefully things will improve from here on in.

Kezza

FNQCairns
27-09-2005, 11:23 PM
Nice find :) That was what I was getting at above. I tryed to tie in what was happening when you tilted the engine up to start it and a possible cause of the problem at speed.

To me it pointed towards the float levels and/or the needle and seats, in short a problem with your fuel bowl fuel level someway/somehow. But over the net it just a big guess.

Hope you have found the problem although it may take more than one screw to cause a problem although it may not with a new gasket that was never tight to begin with (you said the mechanic had his way with it earlier).

But really if you work toward keeping the fuel system in tip top shape chances are the old girl will go for ever.
Good luck with the test run.

cheers fnq

Al_Macka
28-09-2005, 10:49 PM
My thought`s .... B LOOK`N 4 A NEW OUTBOARD MECHANIC ......

>:( >:(