First outing fail - Page 3

sunsport350 · 15 November 2020, 10:07

I'll try and find out, the problem is that the store is closed and the guy who is there for a couple of hours a day isn't the mechanic. I think the mechanic comes in when needed at this time, I'll see what I can do.

beamishken · 15 November 2020, 11:03

Quote:

Originally Posted by sunsport350

I'll try and find out, the problem is that the store is closed and the guy who is there for a couple of hours a day isn't the mechanic. I think the mechanic comes in when needed at this time, I'll see what I can do.

I wouldnt stress too much, in all likelihood the tech found a little bit of casting flash that was preventing a seal seating properly. Chances are all the carbs have a similar defect that doesnt get noticed by the person on the assembly line whos doing 100's per day hence the reason for pdi's & warranty to pick up little issues like this.
Hope it goes well for you

sunsport350 · 15 November 2020, 11:17

That's what I thought it would be to be honest, the carbs aren't made at the same factory as the engine so probably a QC issue, I'm pretty confident it will be fine now.

sunsport350 · 28 November 2020, 17:31

I have ran the OB a couple of times, runs sweet. Started on third pull when cold and first pull when warm.

smallribber · 06 December 2020, 07:41

Quote:

Originally Posted by sunsport350

I have ran the OB a couple of times, runs sweet. Started on third pull when cold and first pull when warm.

Looks like it is now all sorted. Have you managed to use it out on the water yet

sunsport350 · 06 December 2020, 08:15

Quote:

Originally Posted by smallribber

Looks like it is now all sorted. Have you managed to use it out on the water yet

Hi, no not yet, probably wont until the new year now.

Turbodiesel · 12 December 2020, 23:32

My only thought is why was the fault not picked up on the PDI?

sunsport350 · 13 December 2020, 08:47

It ran ok for about ten minutes when I went out on it then I could smell petrol and the OB started running rough. I don't know how long they run it for on the PDI

kaman · 18 December 2020, 10:18

I recently purchased a new 9.8hp Tohatsu 4 stroke (same unit as Mercury 9.9hp).
After running it in a bucket for an hour or so it too started leaking petrol from the carb bowl gasket.
On phoning the dealer I purchased it from they knew straight away of the problem.
Apparently Tohatsu were supposed to have recalled the engines that have been fitted with the defective gasket which supposedly is missing a brass ring around the fuel feed.
I'm being sent a new non defective carb to swap over myself.
I've had a 2008 Tohatsu 20hp from new.
It has thousands of hours under its belt and never skipped a beat!
Hopefully this is a 1 off!

sunsport350 · 18 December 2020, 10:26

I was told there were a small batch of OBs with this problem how small I don't know but mines hopefully sorted now and yours will be, the fact they were both not picked up at PDI check could mean they run ok for a while before the problem shows I'm no mechanic I expect someone here will correct me if I'm wrong. Have a good xmas

kaman · 18 December 2020, 10:50

Hi Sunsport.
On removing the carb bowl to check the float wasn't sticking due to crud in the petrol I could see the rubber gasket on the bowl had deformed where the fuel enters from the pump.
The gasket circles around a small domed filter on the bowl.
This is where the leak was (directly below the over flow).
Mines ran fine for a short period at idle and then started leaking when increased the revs to around 1/4 throttle so it doesn't take much to induce the leak.
Hopefully nobody gets caught out when out on the briney stuff.
This sort of thing really shouldn't be happening though - all defective units should have been recalled.
The new outboard is my Xmas pressie so hopefully the new carb sorts out my pre Xmas woes.
Have a merry one .

sunsport350 · 18 December 2020, 11:04

I did get caught out, had a bit of row against the tide wasnt fun, luckily I hadn't gone too far out, I'd gone along the coast line, but I was knackered though.

Fenlander · 19 December 2020, 23:53

Thanks for that info Kaman.

If it's the same design as in the image below of a slightly earlier Mercury 9.9 I can understand how that might allow the gasket to leak. It isn't a great gasket design as it's rubber, round in cross section and sits in a groove on the float bowl flange. Even a new gasket from the maker can be just a bit out in shape and as you bring the two parts together at the final moment you loose sight of the gasket and it can spring a fraction from its seating as you close together.

I guess yours had an issue with one of the places where fuel passes through the flange??

kaman · 21 December 2020, 07:37

Hi Fenlander.
That looks near identical to my Tohatsu carb.
It appears to be leaking from where the fuel enters the bowl.
Hard to see when the carb is mounted on the engine.
A couple of squeezes on the primer bulb when the carb is off and in your hand and you can see fuel ouzing out from this area.