yamaha 55 hp query

madmart · 18 April 2008, 15:11

Hi a newbie here , live in spain so find it hard to get info on engines and stuff. I have a small boat cannot remember the make fitted with a yamaha 55 hp two stroke , the code on the engine is 55 be with 663 underneath . Anybody know anything about these engines ie;how many cylinders reliability any known problems etc . Any help would be great thanks

Locozodiac · 18 April 2008, 19:25

Quote:

Originally Posted by madmart

Hi a newbie here , live in spain so find it hard to get info on engines and stuff. I have a small boat cannot remember the make fitted with a yamaha 55 hp two stroke , the code on the engine is 55 be with 663 underneath . Anybody know anything about these engines ie;how many cylinders reliability any known problems etc . Any help would be great thanks

Photos of the interior, exterior will help a lot...

madmart · 18 April 2008, 19:41

It is just the outboard I am interested in getting info for at the moment stuff like plugs number of cylinders , year etc

Poly · 18 April 2008, 21:32

Quote:

Originally Posted by madmart

It is just the outboard I am interested in getting info for at the moment stuff like plugs number of cylinders , year etc

easiest way will be to take the lid off and count the number of cylinder/plugs/HT leads.

Jizm · 19 April 2008, 13:40

pic and serial no. of the motor would help.

madmart · 19 April 2008, 22:09

I do not have the full serial number of the outboard but it appears to be a 2 cylinder it is also a 2 stroke which runs on 100-1 premix the engine code is 55BE and underneath it has 663 stamped on the plate. It does appear to be very similar to a mariner engine I looked at on ebay,but I have no real experience of outboards so please any help would be great

Jizm · 21 April 2008, 16:30

does it look like this , but with yamaha on on the hood?

external:

Jizm · 21 April 2008, 16:31

internal:

Jizm · 21 April 2008, 17:28

same as this perhaps?

http://cgi.ebay.co.uk/yamaha-55-outb...QQcmdZViewItem

madmart · 22 April 2008, 00:32

Thanks Jizm , it is definitely the 2nd motor the one on ebay , though to be fair the first one also looks identical. do you know anything about these motors ? they seem to be popular in the states , not sure about europe . Sorry I took my time to get back to you I had a family problem . the one on ebay has very similar serial numbers and looks identical. Please any more info would be great Martin

9D280 · 22 April 2008, 18:18

Hi Madmart, welcome to Ribnet!

OK, sounds like you have something very similar to what I have hanging on the back of my boat. - Even down to the "663" series chassis number. The "663" means you have a 1979 vintage machine, BUT I would question the 100:1 mix. mine is rated for 50:1. Do you have something on the engine (official plate or similar) that confirms that? I say that because if you do in fact have a 50:1 engine and only give it 100:1 you will seize it in a matter of minutes!

Anyhow, back to your questions:
Definetly 2 cylinders - quite long stroke so very torquey. Also very noisy! (well, compared to the shorter stroke 3 cyl that replaced it) As for reliability, mine's still running nearly 30 years after it was built, so they can't be that bad! So far any problems I've found are the sort of things you'd get on any engine of that age - i.e. mostly corrosion related, but I know the vast majority of it's time before I bought it was spent moored in salt water. It now has a new set of anodes as the old ones had been doing their job quite well and one or two electrical "bullet" connectors have been replaced, but apart from that it starts & runs OK.

One thing I would say about the Ebay one - the lid is on back to front!

Hope this helps!

madmart · 22 April 2008, 22:58

Thanks for getting back to me , there is a sticker on engine saying 100-1 premix ,anyway have run it at that and no problems , what about the plugs ? easy to buy ? any other problems that you know of ? gearbox oil ? and how thirsty ? so far it seems to be quite heavy with petrol but I will put up with that if reliable can you still get piston rings / pistons etc thanks any help deeply appreciated

Nos4r2 · 22 April 2008, 23:40

What plugs are in it?

madmart · 23 April 2008, 01:55

I do not know what plugs are in at the moment, in Uk with family problems. Whatever plugs are in work ok but are over 2 years old !! Just do not trust spanish mechanics to get the right plugs , they start and run it ok but want spares as well, as I have a 10 mile licence and with premix do not want to take any chances with those distances . ( a hang over from my puch moped days !!)

9D280 · 23 April 2008, 11:21

MAdmart,

I'm going from memory here 'coz I'm away with work, but mine uses NKG B8/HS10 or Champion ?78C (I can't remember what the "?" is, but if your dealer has the book, you should be able to work it out). It's an M14 short reach. I had a prroblem finding the NKG one, so bought two of the Champion ones and was assured by the chap in the motor factors that it was a popular size. I suspect the NKG is probably still sold,but with a different "name".

Having said that, your engine may be specified with a different plug if you have a 100:1 variant....... My suggestion would be to when you next see it, look & see what's witten on the plugs!

I have no idea about the fuel consumption yet, as I discovered very quickly that my propeller is way wrong sized for the boat, so I am not running above about 2/3 throttle at the moment so I don't blow the engine up. It's reasonably economical like that! I'll need to get back to you on the thirst when I get a more appropriate prop........

Nos4r2 · 23 April 2008, 18:16

If you've got B8HS10 or BR8HS10 in there then you can use normal B8HS or BR8HS in there (cheaper and easier to find-bike shops sell them). All you have to do is regap them to 40 thou. (which is what the 10 suffix means).

9D280 · 25 April 2008, 13:45

I have found the paperwork - it's a Champion L78C - I got two for a fiver!

Cheers for the info Nos, that was what we couldnlt figure out from the "official" stuff in the Motor Factors...... Maybe 'coz they are designed as bike plugs?

madmart · 10 May 2008, 19:45

Thanks for the info guys very helpful and can get the plugs sorted before I return , but just one more question that totally slipped me does the engine have points or some sort of cdi unit ? and if points any idea what the gap is or where to get them cheers Martin

9D280 · 12 May 2008, 11:22

It's a CDI so no points to worry about. From memory the "timing coil" under the flywheel has some adjustment, but as mine seems to be set up OK I've not been in to play with it!

AHH#pG# · 11 August 2009, 11:27

Hi folks stumbled onto this thread looking for info i know its so last year but maybe someone around from the original posting ,ok i got a 55 HP Yamaha similar to the ones above its a 663 but its a BM ,now i have done a load of digging on the net and all i done is confused myself , says 663 is 1974-1979 but 55BM is 697 1979 .
http://continuouswave.com/whaler/ref...odelGuide.html

now acording to this there is a letter stamped on the plate (circled) S
http://continuouswave.com/whaler/ref...odelGuide.html
here it says the motor is 1980 last of the line maybe ??
anyway any help to id the proper year and model and how many parts are compatible with new 2000+ motors cheers