Johnson 15hp 2-stroke. Post purchase checks & service.

[Fenlander]

Carb kit just arrived, a pattern one but it all looks good. Every single part you could want. As mine has no issues and was clean internally I'll just use the gaskets this time and save the rest.

Parts are a little harder to come by for this motor than the Mercury, Mariner, Yamaha, Tohatsu etc portable OBs of the same age but using one of the USA parts diagram websites and then Googling the part number has found what I need so far.

The carb kit came from an outfit called Outboard Spares Unlimited of Maidstone via their Ebay shop. They were helpful and quick to deliver, also commenting their stock for older/unusual motors was far greater than just the Ebay listings.

[beamishken]

Originally Posted by Easedalenovice

You could just keep a can of carb cleaner in the car. A few squirts of that in the air intake usually sorts many carb issues when on a day out

Squirting carb cleaner into the air intake will do nowt useful apart from maybe help the engine fire on the flammable liquid. Certainly wont be cleaning anything meaningfull

[smallribber]

Originally Posted by Fenlander

Technically incorrect. Anything sprayed in the air intake just goes through the 1" dia (or so) throat of the carb into the engine in a spilt second which is not the place blockages occur. It may help an engine start for a few seconds but will not resolve the problem.

Running issues that appear out of the blue are so often idle or main jet blockages from debris that has sat in the bottom of the float bowl or even varnish/gum build up from older fuel. Only taking off the float bowl, cleaning out and clearing the jets can sort the issue. Nothing sprayed into the intake gets through to these fuel flow paths.

It just resolved a problem on both my 9.8 and 15 hp so it worked for me.

[smallribber]

Originally Posted by beamishken

Squirting carb cleaner into the air intake will do nowt useful apart from maybe help the engine fire on the flammable liquid. Certainly wont be cleaning anything meaningfull

Interesting that they call it carb cleaner don’t you think.

[beamishken]

Originally Posted by Easedalenovice

Interesting that they call it carb cleaner don’t you think.

Yeh its used for cleaning stripped carbs, squirting through the jets to remove contamination. It might clean the venturi but it wont resolve any problems like dirty jets etc.
You keep thinking its resolved problems if you like but it aint doing anything sprayed into the air intake

[Fenlander]

I'm pleased for you BP but it does not go into the fuel passages unless you are using it with the carb removed and fully dismantled which is what it is made for. That is why it is called "carb cleaner".

As Ken says...

[beamishken]

Originally Posted by Fenlander

I'm pleased for you BP but it does not go into the fuel passages unless you are using it with the carb removed and fully dismantled which is what it is made for. That is why it is called "carb cleaner".

Wasting our time I think[emoji6][emoji106]
The guys Just looking for an argument.

[Tommy c]

Originally Posted by Fenlander

Carb kit just arrived, a pattern one but it all looks good. Every single part you could want. As mine has no issues and was clean internally I'll just use the gaskets this time and save the rest.

Parts are a little harder to come by for this motor than the Mercury, Mariner, Yamaha, Tohatsu etc portable OBs of the same age but using one of the USA parts diagram websites and then Googling the part number has found what I need so far.

The carb kit came from an outfit called Outboard Spares Unlimited of Maidstone via their Ebay shop. They were helpful and quick to deliver, also commenting their stock for older/unusual motors was far greater than just the Ebay listings.

I've used this website for years
https://www.marineengine.com/parts/j...&model=J15RSTD

[Fenlander]

Yep that's the one I'm using Tommy, really useful site.

Carb back together and fitted, looking clean.

A side job was the fact the tilt lock lever knob was missing and the lever itself was hard on old fingers. About £30 inc post from the USA for the knob and seemingly unavailable in the UK. A very capable lifetime sailor and fabricator neighbour offered a sheet of 20mm HDPE for me to make my own. Plastic crafting isn't an area of expertise for me but a combination of cutting, sanding and drilling then heating with a red hot nail to get the slot a snug fit for the OB's lever then finally fitting a grub screw and it looks/functions OK.

[willk]

Originally Posted by beamishken

The guys Just looking for an argument.

[Fenlander]

Water pump today. I bought a full OE pump kit. Logic being in its 20yr life probably only had the impeller changed each time. On this motor the OE pump baseplate is stainless with a teflon type coating which you can see has worn away under the impeller on the existing one. Also the grommet to the leg water pipe was worn oval and the pump top seal to the driveshaft had worn to a slightly greater diameter than the driveshaft hence lost its full seal. So plenty of reason to get it 100% sorted now.

Checking the new housing and its stainless liner on my flat marble slab for such testing it was fractionally bowed so would have a less than perfect seal. I brought it flat with 400 wet and dry lapping in on said slab.

The correct Johnson procedure for the pump assy requires sealant on the baseplate and housing plus the outlet grommet and a large O-ring on the pump top are to be glued in position. So I'll let that cure overnight, hence the stack of sockets weighing the O-ring down..

Used the workmate as the ideal lower unit support.

[Max...]

This is all bloody willk's fault...

Originally Posted by willk

There's gonna be at least:

1 A stripdown thread...

[Fenlander]

I know, but for Willk I was just going to spray it with carb cleaner from a distance then call it serviced.... and beware if the weather holds this Sat thread 2 is a serious possibility.

Edit: I see thread 2 is already covered above so it’s thread 3 next… right old pace this retired life.

[Fenlander]

Long and enjoyable day out. The Johnson propelled three adults along nicely at 15kts with a gutsy midrange pickup... then suffered terminal overheat failure. 1.5Nm paddle back in. These things happen... not messing about... it'll be dismantled for spares by Monday.

[Steve509926]

Hi Fenlander, when you say terminal? That's it, kaput, knackered?

[willk]

Crikey - that sucks. Good everyone made it back ashore with no losses other than sweat. Backups worked.

On a more personal note, I'm disappointed that your Johnson folded and we didn't reach the Natural Conclusion...

...resale

[69cmw]

Originally Posted by Fenlander

Long and enjoyable day out. The Johnson propelled three adults along nicely at 15kts with a gutsy midrange pickup... then suffered terminal overheat failure. 1.5Nm paddle back in. These things happen... not messing about... it'll be dismantled for spares by Monday.

I thought your sib was grey 🤷

[Fenlander]

Yep terminal in my book as the white paint on the head is burnt dark brown and it will pull over but not start, likely picked up on the bores.

These things happen albeit very rarely thankfully. Unusually I was carrying “guests” rather than usual crew. One of them had never been in a smallcraft before so their mind was concentrated. We managed 2.5kts paddling with 5ft oars. As the OB was new to me and inexperienced folks were on board I’d planned the outing for the prevailing wind to assist return in case of trouble… never really expecting to need that help.

Yes my Aerotec is grey, we happened to be sea trialling an older red one today.

[Steve509926]

Originally Posted by Fenlander

Yep terminal in my book as the white paint on the head is burnt dark brown and it will pull over but not start, likely picked up on the bores.

These things happen albeit very rarely thankfully. Unusually I was carrying “guests” rather than usual crew. One of them had never been in a smallcraft before so their mind was concentrated. We managed 2.5kts paddling with 5ft oars. As the OB was new to me and inexperienced folks were on board I’d planned the outing for the prevailing wind to assist return in case of trouble… never really expecting to need that help.

Yes my Aerotec is grey, we happened to be sea trialling an older red one today.

That really sucks David, back to the trusted Tohatsu!

[Fenlander]

Yep. Perhaps I should relax into that being where we are with the weight/power combo.