Mariner 90hp 2 stroke

CJL · 29 January 2012, 23:21

Evening all,

We have a 90hp Mariner on the back of our Ribcraft and it works perfectly at low to medium speeds. We've recently fitted a new battery and being used frequently its got "fresh" fuel in it.

We keep the oil in the engine oil tank low to stop it dripping when tilted up but not in the alarm range.

However at high speeds a buzzer sounds in the throttle box. Any ideas what it could be? I'd rather rule out all the basics before splashing the cash with a marine mechanic!

Thanks in advance.

Chris

Searider · 30 January 2012, 09:53

Buzzer is for overheat as well as low oil iirc.

Not getting hot is it?

jezza2011 · 30 January 2012, 09:55

Is it the 2 stroke?
if so could be the alarm unit, head temp sensor, broken wire ,poor connections, broken wire to the remote ( like mine) or doddgy connections in the remote, or key switch.
Bad battery conectoins ( had this and made the alarm go a off )
simple way is to disconnect the apropreate cables to sensors/switches and test.

Mines the other way round a the moment. beeps like crazy at low revs and at high its fine.
no cooling issues at all.

is it watering ok? could be the impella not cooling it at high revs.

9D280 · 30 January 2012, 10:22

Not knowing what flavour of engine it is (2/ 4 / etc stroke) The high level observation I would thorw in here is that on older machines the alarm was usually trigered by a switch (e.g bimetallic strip type thing on the temp, on / off on the oil float) and so for it to be squealing (if it is an older 2- stroke) I'd be guessing a short or an uncalibrated sensor. Modern ones controlled by the engine management I'll leave to the experts!

You say you keep the oil level low - does topping it up help? I have had a couple of car fuel gauges in the past which had a sticky float mechanism, and didn't register I had filled it until the first pothole / speed bump loosened the float. Is your oil level float sliding properly, or is it stuck at "warn" and doesn't move when you drop the engine? If the float is towards the rear of the tank it will register "low" as you tilt & the oil moves forward.....

uncle al · 30 January 2012, 15:34

is the buzzer constant or intermitant?one is water and the other is oil, look in your owners h/book fot which is which.We have had in the past (swing that light) on the two strokes where the temp sender is corrosion or flakes of paint setting of the o/heat alarm, remove clean and refit with silicone grease, if its oil is the float in the oil tank rising and falling as it should?is it a wiring problem, note the oil should not leak out of a full tank when tilted up bad seal on the oil tank cap, the little valve under the breather knackered? tank cracked?

yoyo · 30 January 2012, 15:39

Quote:

Originally Posted by jezza2011

Is it the 2 stroke?

There may be a clue in the title. Mariner 90hp 2 stroke

jezza2011 · 30 January 2012, 17:40

YOYO yep saw that after I sumitted the reply .. :-)

CJL · 30 January 2012, 17:51

Quote:

Originally Posted by Searider

Buzzer is for overheat as well as low oil iirc.

Not getting hot is it?

Surely if it was getting hot the buzzer would sound and continue to sound until it cooled not just until you backed off the throttle?

Chris

CJL · 30 January 2012, 17:54

Quote:

Originally Posted by jezza2011

Is it the 2 stroke?
if so could be the alarm unit, head temp sensor, broken wire ,poor connections, broken wire to the remote ( like mine) or doddgy connections in the remote, or key switch.
Bad battery conectoins ( had this and made the alarm go a off )
simple way is to disconnect the apropreate cables to sensors/switches and test.

Mines the other way round a the moment. beeps like crazy at low revs and at high its fine.
no cooling issues at all.

is it watering ok? could be the impella not cooling it at high revs.

Got a good strong impellor.
Batt new with clean connectors on to it.
Not sure about sensors sound like a mechanic test to me!

chewy · 30 January 2012, 17:57

Not something shorting out in the control box is there?

CJL · 30 January 2012, 18:01

Quote:

Originally Posted by uncle al

is the buzzer constant or intermitant?one is water and the other is oil, look in your owners h/book fot which is which.We have had in the past (swing that light) on the two strokes where the temp sender is corrosion or flakes of paint setting of the o/heat alarm, remove clean and refit with silicone grease, if its oil is the float in the oil tank rising and falling as it should?is it a wiring problem, note the oil should not leak out of a full tank when tilted up bad seal on the oil tank cap, the little valve under the breather knackered? tank cracked?

Constant buzzer. Unfortunately not got a manual for it. Any ideas? Its a 1998 engine
Tank OK. Rubber seal on tank just old so becoming perished I suspect.
Oil float must be OK as it works at all angles and fill states.

CJL