A few questions

[Graham E]

Just joined and fairly new to boating, but have owned our current boat for 3 years now and have been improving it all the time.

 

However after this years trip the engine has given us a problem.

 

It's a Mercury 2 stroke 9.9.

 

The problem is it has trouble ticking over and if I can get it to tickover it won't drive without the choke, if you push the choke in it will stall. Have removed the engine cover and taken a look but not seeing much. I am quite willing to fiddle around with the engine but never worked on a boat engine before.

 

We have decided to carry out a few jobs on the boat ready for next year, New paint, graphics and a few other things so it looks even better as the inside is complete.

 

We are thinking of a new engine but if we can't afford one then we will have to keep this one.

 

Anyway my questions........

 

 

What is wrong with our engine? Is it worth repairing? Is there a better engine? (I know there is but which one)

 

What is the largest fuel tank we can fit?

 

What is the best paint for glassfibre?

 

Thanks in advance

[benfordboy]

Just joined and fairly new to boating, but have owned our current boat for 3 years now and have been improving it all the time.

 

However after this years trip the engine has given us a problem.

 

It's a Mercury 2 stroke 9.9.

 

The problem is it has trouble ticking over and if I can get it to tickover it won't drive without the choke, if you push the choke in it will stall. Have removed the engine cover and taken a look but not seeing much. I am quite willing to fiddle around with the engine but never worked on a boat engine before.

 

We have decided to carry out a few jobs on the boat ready for next year, New paint, graphics and a few other things so it looks even better as the inside is complete.

 

We are thinking of a new engine but if we can't afford one then we will have to keep this one.

 

Anyway my questions........

 

 

What is wrong with our engine? Is it worth repairing? Is there a better engine? (I know there is but which one)

 

What is the largest fuel tank we can fit?

 

What is the best paint for glassfibre?

 

Thanks in advance

 

Graham

 

Not been able to PM you as you are a new member.

 

At the risk of offending all on the forum (Not my intention!) there is an excellent Norman dedicated site at www.normanboats.co.uk

 

Here you may find answers to all your questions.

 

Of course there are many boaters here that can & will help.

 

Mods - sorry if this is offensive posting to another forum....

 

& in answer -

 

Tickover - Maybe a fuel starvation prob , blocked idler jet poss or smeg in carb leading to no tickover.

 

Engine - a 20hp stroker will be thirsty at revs , a 4 stroke ob will be a better choice - We have a Honda BF15 which copes well with tidal rivers , rivers & canals on our Norman 22.

 

Paint - International / Blakes Pearl White is a good match to the aging Norman gelcoat. Preperation is everything when painting a GRP boat.

[Graham E]

Thanks for reply, will have a look at that website.

 

Did think fuel problem and had a rumage around but nothing obvious.

[JDR]

benford boys got it. I dont know this engine but general principle is: is fuel coming out of tank ok? Is there a filter between tank and carb-is it transparent? Are you getting fuel through line to carb input? Try tapping side of carb to release a sticking jet/fuel float valve.If that doesnt work try draining carb float bowl.Next step is to take carb apart.Sometimes spraying carb cleaner into air inlet will break down blockage.Once you fix it empty tank to make sure there isnt any debris in the bottom.You can buy stuff to pour in tank to seal any rust debris (Pettseal?)Good luck.

[Graham E]

Thanks for that.

Checked fuel strainer thing in tank and is clean.

Plastic fuel bowl thing has petrol and you can see petrol going in after I emptied a bit out but there did seem to be some bits in it.

Fuel getting to carb as it sprayed my face when I pulled pipe off.

Will try some carb cleaner and see what happens.

[JDR]

When you operate the choke all you are doing is restricting the air flow to make the air/fuel mix richer and more combustible from cold.If it only ticks over with choke applied that indicates the pilot jet is unable to supply enough fuel and you are compensating for the lack of fuel (running lean) by reducing the air flow to a point where a usable air/fuel mix is established.The only other thing which would make an engine run lean is too much air-unlikely given what you've described but worth checking the air filter does not have any tears/holes.

[Graham E]

Didn't notice an air filter, unless it is not fitted to the inlet bit of the carb like it would be on a car.

 

Carb inlet (I assume) where the butterfly flap is, is sideways on my engine or would it be under the pull cord thing.

 

Sorry don't know the names of the parts yet.

[JDR]

Can you bypass the filter to test if that is restricting the flow. In an ideal world you would want to use fresh fuel and a non contaminated container.The carb is getting some fuel or it would not run at all.

[Graham E]

It has fresh fuel and tank is clean, will try and bypass the plastic filter thing and see if that helps.

 

It was ticking over quite nicely for ages by itself without the choke but when we went into drive it cut out and would then only run with the choke out and as time went on you could feel it getting slower not that it was going fast before.

 

Thanks for help

[JDR]

Carbs aren't complicated there isnt that much that can go wrong.If you try everything suggested there is only the float/float height,float fuel valve and pilot jet to check.An almost invisible particle of dirt in the wrong place can stop a carb working.

[JDR]

One final thought-throttle cable.Is cable connected direct to a twistgrip or is there a cable run to inside of boat? Outside bet but definitely worth checking.Twistgrip should snap shut.Is there an external throttle linkage for carb? There should in theory be a small amount of slack before cable operates carb.

Edited August 24, 2011 by JDR

[Graham E]

No idea what you mean on your last post. But I was thinking the choke could be sticking.

On the side of the carb are some metal rod linkages. When I pull on the choke on the lever box it opens the choke a small bit but not as wide as the choke fitted to the engine.

The throttle opens things up quite a bit.

 

When I go up the boat next to have a fiddle around will get some photos to make things easier.

 

Thanks for your help.

[AlanH]

2 strokes are notorious for sooting up plugs when kept on tickover for longish periods. You would be far better off with a 4 stroke Honda or Yamaha. Both are reliable and will tick over all day. The Yamaha is quieter than the Honda.

[Graham E]

Thanks would prefer a 4 stroke as not seen another 2 stroke and it is quite noisy when running.

 

Plugs were in a bad way and ave fitted new to see if that was a cause for the bad running but it wasn't.

 

Are 4 strokes better on fuel as I seem to use quite a lot.