Starting probs with older Mariner 15hp 2str

ferryden · 02 August 2011, 00:32

I've been starting the engine to warm up relatively easily, then tilting up to wheel the SIB (QS 340) and engine to launch ramp down the road, after tilting down I then find it difficult to restart again...
Can anyone tell me what problem the tilting is causing and whether I should re-choke or not to get going asap...I've had it run for a short time as I slowly reverse out, then conk out again once out in the bay... can be an embarassing pain in the ass.
After a while I have eventually got going (knacked!) and not then had a problem once warmed up, so I don't think there is any real issue with the engine as it CAN run ok...
Any clues?...
Cheers folks!
x
F

kubcat · 02 August 2011, 05:30

On mine I need to work the choke in and out continually for a minute or so till it's warm enough. Full choke floods it as it is too rich for the climate in Sydney.

I have no idea if any others are like mine but my marine mechanic assures me it is okay and to just live with it.

Fenlander · 02 August 2011, 09:44

Going back a couple of years I had a 20hp Mariner from the mid 80s on my GRP boat. It was in great condition but the one thing that could catch it out was to start it, run for a very short while, stop and shortly restart. It was never clear if it needed choke or not for the restart and could take 20+ pulls to get it going by which time you had to have the choke right in as it became flooded.

As it would start really well 2nd pull from cold and 1st pull from hot I just avoided the circumstance you are creating.

9D280 · 02 August 2011, 09:58

I assume you are warming this up on muffs? Could it be that your idle is set for zero exhaust back pressure and so when it is in the water needs just a touch more idle throttle?

problem with outboard chokes is they are usaully either "on" or "off" - there is no halfway unless you guddle it a bit. Since the rebuild my Merc now needs a couple of mins with the fast idle lever just slightly up to warm up - it used to "just fire & go" - the fast idle lever was the quickest way to stall it.

if you have to take the trolley / trailer back to the car could someone sit with it by the pier warming it up in the water?

ferryden · 02 August 2011, 14:00

Thanks guys... As I'm on transom wheels, I have been warming up in neutral for a while before cruising out...then seems to stall when put into forward gear, following which the frantic tugging starts!
I've also not been sure whether it then has a need for more chor less choke..so will go for the part-choke option! :-)
It's at least comforting to know I'm not the only one!!
Cheers
F

9D280 · 02 August 2011, 14:17

Also just struck me - if it's premix, your long spell at idle with a cold engine will likely be coating your sparks plugs with a nice layer of unburnt oil........

willk · 02 August 2011, 14:32

Quote:

Originally Posted by ferryden

I've been starting the engine to warm up relatively easily, then tilting up to wheel the SIB (QS 340) and engine to launch ramp down the road, after tilting down I then find it difficult to restart again...

I read this to mean that you start the engine away from the water to warm it. 9D280 asked the question for me - do you run it on muffs or in a barrel?

ferryden · 08 August 2011, 21:34

..In a barrel mate...

ferryden · 08 August 2011, 21:36

I think I may have been keeping the choke out a bit long before putting back in... been reading a good article on Starting Outboards in a boat mag at the weekend...
Thanks guys...
:-)

m chappelow · 08 August 2011, 23:17

On some older engines yamaha/mariner ,when pull out the choke knob as well as choking the carb with a flap it also squirts some fuel into the carb which can make things harder after a short cold start .

when you tilt its probley the float in the carb thats passing fuel .
Bit extreame but
i suppose you could do what the RNli do with the atlantics and have a drum of water and a hose to the engine on some muffs whilst your launching

Festinghouse · 09 August 2011, 07:04

Quote:

Originally Posted by ferryden

I've been starting the engine to warm up relatively easily, then tilting up to wheel the SIB (QS 340) and engine to launch ramp down the road, after tilting down I then find it difficult to restart again...
Can anyone tell me what problem the tilting is causing and whether I should re-choke or not to get going asap...I've had it run for a short time as I slowly reverse out, then conk out again once out in the bay... can be an embarassing pain in the ass.
After a while I have eventually got going (knacked!) and not then had a problem once warmed up, so I don't think there is any real issue with the engine as it CAN run ok...
Any clues?...
Cheers folks!
x
F

my guess is that tilting the engine is causing fuel to syphon back into the tank, leaving just a small amount in the carbs for it to run briefly, but causing an air pocket in the pump - which only works with fuel in it!
next time, once youve lowered your engine into the water re prime it until the builb is rock hard. i am certain this is what is causing my problems as repriming seems to sort it for me.

Scrottocks · 17 August 2011, 11:03

Quote:

Originally Posted by ferryden

I've been starting the engine to warm up relatively easily, then tilting up to wheel the SIB and engine to launch ramp down the road, ...............
F

Err, no mention of muffs or a barrel. You weren't warming up with no water were you? (!?)

Arthur

ferryden · 17 August 2011, 13:51

Quote:

Originally Posted by Scrottocks

Err, no mention of muffs or a barrel. You weren't warming up with no water were you? (!?)

Arthur

4 posts back mate!
,-)