Plastic (and now broken) Yamaha outboard oil drain plug

[Daydream believer]

That is a bit far from Bradwell.
Of hand, I am not sure what plastic one would use with hot oil
Any model engineer could make one in a few minutes if they had a 16 * the correct pitch die.plus the plastic to hand
Bit longer if one had to cut with a single point cutter though.

 

[dankilb]

The previous owner of my Yamaha F5 managed to overheat it such that the plastic dipstick melted! (It was a beer token giveaway and runs fine so I wasn’t fussed)

 

[mikeywil]

Might this do it?
View attachment 135910

On the other hand the drain plugs on aluminium outdrives and on my outboard are stainless steel and nothing bad happens.

Thanks for the idea. Great price!! The page says: Maximum continuous working temperature 100°C.

I'm thinking that might not really be a high enough level?

 

[mikeywil]

That is a bit far from Bradwell.
Of hand, I am not sure what plastic one would use with hot oil
Any model engineer could make one in a few minutes if they had a 16 * the correct pitch die.plus the plastic to hand
Bit longer if one had to cut with a single point cutter though.

Absolutely too far! Although once I get this thing fixed, then a trip up there by water would be one of the trips I'd like to do.

 

[Chiara’s slave]

On the very (off topic!) topic of Pro Furl parts - check out this affront to reason and economics:

(16mm clevis pin - threaded M12 both ends with standard nylocs)

The price sticker isn’t evidence of a greedy swindlery either - the boatyard just use them as a way to record cost plus carriage and VAT for when punters come to pay up.

There were sharp intakes of breath and choice words from the boatyard staff as well as from me!

I recently paid £112 trade for a profurl pin for a multihull. Just 14mm, with S/S retainers instead of the plastic caps they give you as std.

 

[mikeywil]

The saga continues... I ordered a couple of new bungs - different designs as the profiles all vary. My plan was to get it sorted this weekend. They arrived yesterday and I checked them visually against the original. Somehow I'd gotten the measurement of the thread wrong as the thread is 17.5mm diameter. Seems like a very odd measurement... so am now going to try an M18 bung in there, but have some doubt as to whether it will fit without damaging the casing.

 

[Daydream believer]

The saga continues... I ordered a couple of new bungs - different designs as the profiles all vary. My plan was to get it sorted this weekend. They arrived yesterday and I checked them visually against the original. Somehow I'd gotten the measurement of the thread wrong as the thread is 17.5mm diameter. Seems like a very odd measurement... so am now going to try an M18 bung in there, but have some doubt as to whether it will fit without damaging the casing.

Not only diameter, but pitch. 18mm comes in 1.0 ,1.5 2.0 (13 TPI) & 2.5pitch. Being plastic I would imagine the coarser pitches
Could be 11/16 BSF (17.465mm) with 14 TPI. Lots of items are still made using the whitworth threads. A thread gauge would give you the pitch for starters.
Another reason I said that if I was doing it I would want to fit to the engine.

 

[mikeywil]

Not only diameter, but pitch. 18mm comes in 1.0 ,1.5 2.0 & 2.5pitch. Being plastic I would imagine the coarser pitches
Another reason I said that if I was doing it I would want to fit to the engine.

Yep - I'm fairly sure the pitch is 1.5... I can measure 6mm across four dips/five peaks.

 

[VicS]

The saga continues... I ordered a couple of new bungs - different designs as the profiles all vary. My plan was to get it sorted this weekend. They arrived yesterday and I checked them visually against the original. Somehow I'd gotten the measurement of the thread wrong as the thread is 17.5mm diameter. Seems like a very odd measurement... so am now going to try an M18 bung in there, but have some doubt as to whether it will fit without damaging the casing.

The plug should be available , There's no suggestion anywhere that it's not

You presumably have the part number .......... 6G8-13471-00-00, I believe

Try other dealers. Start with Wills Marine in Devon

Or Google the part number

 

[mikeywil]

The plug should be available , There's no suggestion anywhere that it's not

You presumably have the part number .......... 6G8-13471-00-00, I believe

Try other dealers. Start with Wills Marine in Devon

Or Google the part number

Yeah - it’s “available” in lots of places but those I’ve been in touch with say it’s not in stock and they’d need to get it in. A Yamaha dealer said it would have to come from Japan…

 

[QBhoy]

Off topic, but the spec for the 90's 9.9 Yamaha is identical to the 15, except for the two jets, which are cheap as chips and easy to replace.

I understand the reason for this is that in the land of the free, you need some sort of licence to drive a boat with more than a 10hp engine, so Yamaha jimmied the jets to decrease the HP rating

I’d say this might be the rarer 4 stroke 9.9 they made. Perhaps not the 9.9 2 stroke (given the description) that’s the same as the 15. They of course don’t have an oil drain…

 

[mikeywil]

I realise I never updated this. I sourced an OEM spare in NL (Honda Motorcycle Parts, Kawasaki, Suzuki and Yamaha Motorcycle Parts - ATV, Classic Bike, Dirt Bike Parts) which cost €25 including delivery to the UK.

Everyone’s advice here was super helpful.

Next up… a new thread soon to be added about the starter motor…