Yamaha In Boston Whaler

[Ramtour2]

I bought a Boston Whaler Rage with a Yamaha 650 engine. The numbers on the engine plate are J650C 6R8 021181. Are there different versions of the Yamaha 650. I've seen 62T, X etc. Does anyone know what version I have and what engines are compatable with the 650? Can I put a 701 into the boat instead? Would I need the complete electrical box with the 701. The one I have is a single carb. Also does anyone know if the jet drive is the same as in the PWC's. Thanks !!!!

[Technical Support]

There is only one 650. No you can't swap blocks, the external parts are different.

[Ramtour2]

Is there a 650 with dual carbs called a super 650? What is the 62T vs X stuff?

[Technical Support]

62T is a 701. There is only ONE 650 block.

[torquenut]

You can put anything in the place of the 650 as long as it is a two cylinder.
SBT Guy is right on that parts from a 62T to a 6M6 are not interchangable. But yor electricals can be used on a 61X and even a 62T. Your next problem will be the pump. You are correct in that the pump is a stock 650 pump. you would need to change to pump for any big Hp as say a 62T in the 701 or 760.
I hope this helps. I see your in NC so am I if you want drop me a line I will soon have a 62t out of a PWC you can check it out to see if it will easyly work. The exhust is another problem as the 6M6 and the 61X blocks use the forward side orientation of the exhuast and the 62t went straight left side and back. :D

[Chester]

Your best bet is to put a 701 (61X) engine in place of the 650. It's a very simple swap and you can use all your original electrics. The exhaust manifold and the carb will bolt right on but you have to use the 61X intake manifold & reeds. The carb will have to be re-jetted and you should change the impeller (they both use the same diameter pump). The exhaust ports on the 701 engine are larger than the 650 and therefore, won't match up perfectly. If you like, you can grind out the manifold to match the ports on the cylinders but it's not necessary, be very carefull not to grind too much. I've done over a dozen of these swaps in Super Jets and Wave Runners and it works out great.

Chester

[Technical Support]

...and in the end you will have bought hundreds of dollars in parts, done hours work, for a gain of...a *couple* MPH at best, and worse fuel ecconomy. a 5-10 HP gain doesn't respond the same way in a boat than in a tiny stand-up or small runabout.

Sometimes people lose sight of the fact that just because an idea is a good one on paper doesn't mean it's worth it. The additional cost to do such a swap is litterally the value of the vehicle in some cases.

I can spend $10,000 and put a 4tec engine in a 1996 Venture if I really wanted to, but it wouldn't be worth it.

[Chester]

If you don't port the exhaust manifold, it's the same amount of labour as replacing the engine with another 650. The 701 (62 HP) has much better porting than the 650 (50 HP) and is a way better engine to add modifications to later on. The 12 horsepower (24%) increase is very noticeable. If you have to replace the engine anyway, put the 701 in.

Chester

[Technical Support]

That's WITH the 701 pipe, intake manifold, carb, and then you still have to buy and install the impeller.

You switch the block alone without the ignition and pipe, and all you are getting is a slightly bored out 650.

[Chester]

Actually, most of the horsepower increase is from the difference in porting. The intake manifold and reeds come with the new engine. The carb is the same with different jets.
Take one of your 650 cylinders and measure the exhaust port height & width, then compare it to the 701. huge difference.

[Technical Support]

OK, my mistake, I misread one line - that he already has a 701. I read it as if he said he already had an electrical box.

If he already has the block, intake and carb, yeah go for it - although there still won't be a dramatic difference in a Boston Whaler - but it will get it back on the water!

[Ben]

I have experience with the Whaler with the 701. My best advise, honestly, live with it like it is or better yet.. get rid of the craft.. it is too heavy.. 2 adults .. 1 needs to move back and forth to fore and aft to get it on plane quick and it wants to fall off plane. meeting other boats and wakes , it is just a constant hassle. My neighbor loved my wv700 and wv1100 but wanted one for his family and got the whaler.. he was sorely disappointed.. like I said.. just to heavy.. good luck..