Identification of old Yamaha outboard Model P250

[Monte NZ]

Hi everyone.
Could any of you very knowledgable chaps please help with the above……I have "run out of puff" as the saying goes
A friend of mine has picked up an old Yamaha outboard that had been dumped in an inorganic rubbish collection.
The only description and can give you is that at a guess, it would be about 15hp to 25hp going on the size of it.
It is painted white on the outside and red on the power head and rewind start unit.
We think that it would be about 30 years or more old.
The little I have found using Google doesn’t help establish the year or the hp.
There was mention that some models are started on petrol and then you switch to kerosene.
Any assistance would be greatly appreciated……….it turns over OK and there is spark

Thanks very much in anticipation.
MonteNZ

[thepetrolist]

Hi there!

I have one of those, its an early 1970’s model. They were made between the late sixties and early seventies. I haven’t found any real info about them, seems to be quite uncommon.

The P250’s can be run on both gasoline and kerosene. They have two carbs, one for gas and one for kerosene. The orignal gas tank that I have is split in two different compartments, because of earlier mentioned feature.
There seems to have been no examples sold in US as new, so if you are located in the US it is probably imported by someone for private use.

As for output, the engine is rated at 15 hp. Some sources claim that it makes 18 hp on gas and 15 on kerosene, but I can’t confirm that.

As for technical specs, it is two stroke, twin cylinder, most probably 250 cc’s (therefore the model name). Regular F-N-R gearbox.

This engine is certainly not made from any lightweight aluminum. It seems to be all cast iron, since it weighs just about as much as a full size ocean liner 😯 😆

Here’s my p250

Fuel switch: pull for gasoline, push for kerosene.

[Monte NZ]

Hi thepetrolist.
Thanks very much indeed for your prompt reply.It is great news to hear that you actually have the same motor,except this one here in New Zealand
is a petrol only one……not kerosene.
It certainly looks the same and thank you for the excellent photos!!!!. My friend is wondering what petrol/oil ratio to use. I think 24 to 1 would be a safe bet. What are thoughts?
Do you have a hand book, and if so, would you be able provide specifications, such as points gap and spark plus info?

While looking at your website I noticed that you have a 1970s 5hp Tohatsu Sea Swallow. Believe it or not ,my neighbour has just had one given to him and has managed to get running nicely. He has the owners handbook for it and I have just spoken to him and he would be delighted to send you a copy if you would like one.

Thanks again for your very helpful reply and thanks to you other AOMCI members for all your help to other outboard enthusiasts round the world!!!
Best wishes
MonteNZ

[kees]

Funny !
A guy from New-Zealand find answers through this forum from a guy in Finland !
very well, I only can say;
It took a bit of time but this new forum works great
thumbs up for the moderators.
regards from the Netherlands
🙂 🙂

[Monte NZ]

Hi Kees
Thanks for your post.
Yes, the moderators are to be congratulated on a great set up!
It’s a great site…….my friend couldn’t believe it when I told him that I had received a reply from thepetrolist in Finland.
And it’s great that I might be able to help him with his 1970s 5hp Tohatsu Sea Swallow and what a coincidence that both thepetrolist and my neighbour
have what appears to be fairly rare outboards…….especially in USA.

Cheers
MonteNZ

[phil]

There is some info at http://www.oddjobmotors.com

I think the owner there is very knowledgeable about the Yamahas of that vintage, also a club member.

http://www.omc-boats.org
http://www.aerocraft-boats.org

[thepetrolist]

Oh silly me, should have noticed the NZ in your nickname!

I have found an inscprition on the engine that says the points are set at 0.20". The gas tank has a fuel mixing instruction sticker on it, and it says "premix gas and oil at 24:1".

Nice coincidence about the Tohatsu. It’s a real odd little engine but cool in its own quirky little way. I would love a copy of the manual since I havn’t got one!

Neither do I have a manual of the Yamaha but I would be delighted to help you guys out in any way I can.

quote kees:

Funny !
A guy from New-Zealand find answers through this forum from a guy in Finland !
very well, I only can say;
It took a bit of time but this new forum works great
thumbs up for the moderators.
regards from the Netherlands
🙂 🙂

Haha, true that Kees! The internet makes the world quite a small place! And to make it even funnier, my brother has a friend who went on an exchange program to New Zeeland from his university, and my brother went on a similar exchange program to Amsterdam in the Netherlands! Went there to visit him last december. Loved the city!

[Monte NZ]

Hi Phil.
Thanks very much for your input…….it looks an interesting site. There was nothing on the P 250 but the 1967/68 P35 Yamaha shown, were very popular here in New Zealand.

Thanks again
MonteNZ

[Monte NZ]

Good morning thepetrolist.
Thanks very much for the info…..very helpful,especially as my friend was going to try running it on 50 to 1 ratio and (heaven forbid!!!) 100 to 1.
I thought it might be 24 to 1, so am very thankful for your reply confirming my thoughts!!
I would be very pleased to send you a copy of the 5hp Tohatsu Sea Swallow manual.
How would you like me to forward……. by airmail or scanned to an email address ?

I have taken photos of my neighbours Tohatsu to forward to you, but still being new to computers, I don’t know how to post them on this website, but I do know how to forward them to an email address.

I have offered to repaint the Tohatsu for him and I have managed to get the correct coloured spray cans, so it should come up just like new.

Best wishes
MonteNZ

[thepetrolist]

Hi there MonteNZ, glad I could help.
I think it is easiest to send it by email. I’ll send you my address in a PM.
I’d be glad to take a look at the pics of your buddys Tohatsu, so feel free to send me those too!

Cheers

[Author]

Posts