JOHN WALSH
New Member
Are the blocks the same on all the two cylender rotary valve timed two stroke rotax seado motars and are the electronics interchangeable?
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Motors
- Thread starter JOHN WALSH
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JOHN WALSH
New Member
Seadoo -rotax blocks
So do the 717 and the 587 share the same block
So do the 717 and the 587 share the same block
JOHN WALSH
New Member
Bolt patern tbo side
Do any of the higher horse power two stroke 2 cylinder share the same tbo bolt pattern as the 587
Do any of the higher horse power two stroke 2 cylinder share the same tbo bolt pattern as the 587
JOHN WALSH
New Member
engine blocks
it's a matter of a gear reduction that I'M TRYING TO RETAIN FOR THIS PROJECT
it's a matter of a gear reduction that I'M TRYING TO RETAIN FOR THIS PROJECT
Dr Honda
Well-Known Member
OK... stop talking in riddle. Seadoo's don't use gear reductions.
Are you talking about an ultralight engine? If you are... that's a little different, but most of them are air cooled, and are reed valved.
Tell us exactly what you are trying to do.
You are asking vague questions, so you are getting basic answers.
Are you talking about an ultralight engine? If you are... that's a little different, but most of them are air cooled, and are reed valved.
Tell us exactly what you are trying to do.
You are asking vague questions, so you are getting basic answers.
JOHN WALSH
New Member
Engine blocks
Ok doctor honda .you almost got it sorry about beating around the bush .i'm looking to use it for q light sport float plane replacement .rotax -seadoo uses rotary valve 582 or 587 same thing it's water cooled with a radiator .iv'e been flying that motor for 6500 hours . But as the saying goes you can never have enough power on a float plane .and a four stroke conversion would be a weight penalty .as well as a financial burden compleatly destroying my profit margin.well there it is in a nut shell ,hopefully i have shed some light on my madness .
Ok doctor honda .you almost got it sorry about beating around the bush .i'm looking to use it for q light sport float plane replacement .rotax -seadoo uses rotary valve 582 or 587 same thing it's water cooled with a radiator .iv'e been flying that motor for 6500 hours . But as the saying goes you can never have enough power on a float plane .and a four stroke conversion would be a weight penalty .as well as a financial burden compleatly destroying my profit margin.well there it is in a nut shell ,hopefully i have shed some light on my madness .
JOHN WALSH
New Member
Project pics
It's a working machine the project is to find an affordable solution to my rotax delema.google tocheck out m squared sprint 2
It's a working machine the project is to find an affordable solution to my rotax delema.google tocheck out m squared sprint 2
Dr Honda
Well-Known Member
OK... if you have a 587 rotary valve lower half... and you are the brave type... you could fit a set of 720 jugs to your case. Basically, the deck hight is going to be wrong. I've never tried it... but yes, they are of the same "Family" type. Since I don't know the rod length, and pin hight off the top of my head... it will be a project in properly setting the port timing, and squash band.
FYI... your engine will be 676cc.
Personally, I would just send your jugs out to have a big bore done. (push them up to 82mm)
Finally, most of the gear boxes I've seen unbolt from the power half. (including the Rotax units) It may be easier to adapt the gear box to a real 720 engine.
FYI... your engine will be 676cc.
Personally, I would just send your jugs out to have a big bore done. (push them up to 82mm)
Finally, most of the gear boxes I've seen unbolt from the power half. (including the Rotax units) It may be easier to adapt the gear box to a real 720 engine.
Dr Honda
Well-Known Member
The flange on the dri-pipe will block off the water outlets.
not follow'n it, chief.
I can see, install'n a mini radiator, looping the system, having a waterpump..etc, but the exhaust side, got me?
JOHN WALSH
New Member
The blocks
That's what i was planning to do the whole time the rebuilt 717 are infinately cheaper and have 20 more horse power i'm expecting to use the same carbs and exhoust and radiat system = gearbox and all the other thing that don't acompany a short block.please let me know if you have any idea of the carb jetting changes neededror
That's what i was planning to do the whole time the rebuilt 717 are infinately cheaper and have 20 more horse power i'm expecting to use the same carbs and exhoust and radiat system = gearbox and all the other thing that don't acompany a short block.please let me know if you have any idea of the carb jetting changes neededror
JOHN WALSH
New Member
Engine block
it's called a radiator lot's of machines use them that don't stay on the water .and no i'm not the americas most wanted guy compleatly different clan.he's been down here didn't have the do dads to fly with me
it's called a radiator lot's of machines use them that don't stay on the water .and no i'm not the americas most wanted guy compleatly different clan.he's been down here didn't have the do dads to fly with me
I'll disregard the "sarcasm" there, but the question is, inwhich i'm sure you know, that the exhaust pipe/muffler has water exiting out of them, from the motors' system. ? was, how you gonna achieve that, with it airborne, or is it a capacity water tank, on board that will keep feeding the cooling system?
Dr Honda
Well-Known Member
He won't be using a "Wet" pipe. On the liquid cooled, non-marine Rotax engines... the exhaust manifold will block off the water jacket going into the pipe. Also, the pipe doesn't need to be cooled since it's out in the open air. But that will effect the question below.
I guess I should start by asking... what kind of carbs are you using? If you are using anything other than the SBN carbs we use... jetting is going to be up to you. The last time I did engine work on an experimental aircraft (with a carb) we used a Posa carb with a mix control... so it was adjustable in flight. The other thing... I don't know how well the SBN carbs will work as altitude changes. So, I don't recommend using them.
If you are flying from MSL, and going over 3000 or 4000 ft... I would say you are going to need an adjustable carb.
JOHN WALSH
New Member
Engine blocks
Sorry about the sarcasm seadooya the block off plate and not having to cool the exhoust is the answer.dr honda i will be using the bing 54 .the temp n my aerea stays around mid 80's and i rarely fly over 2000' so it is not necessary for altidude compensating carbs .i will probably refer to what they used on the rotax 618 rave valve twin two stroke .
Sorry about the sarcasm seadooya the block off plate and not having to cool the exhoust is the answer.dr honda i will be using the bing 54 .the temp n my aerea stays around mid 80's and i rarely fly over 2000' so it is not necessary for altidude compensating carbs .i will probably refer to what they used on the rotax 618 rave valve twin two stroke .
Seadooya,
The water cooled Rotax engines made for aircraft (and snowmobiles) do not have a water cooled exhaust. It's not necessary.
John,
None of the Sea-Doo cylinder jugs (587, 657, 717, 787) are interchangeable. The cylinder bolt spacings are all different.
Chester
The water cooled Rotax engines made for aircraft (and snowmobiles) do not have a water cooled exhaust. It's not necessary.
John,
None of the Sea-Doo cylinder jugs (587, 657, 717, 787) are interchangeable. The cylinder bolt spacings are all different.
Chester
JOHN WALSH
New Member
engine blocks
CHESTER I WAS NOT LOOKING TO CHANGE THE JUGS .BUT TO CHANGE THE WHOLE MOTOR AND WAS HOPING THE 717 HAD THE SAME PTO BOLT PATTERN AS THE 582 SO I COULD USE MY ALL IMPORTANT GEAR REDUCTION AND HAVE A MOTOR WITH ANOTHER 20 MORE HORSEPOWER .IT'S NOT ABOUT SPEED IT'S ABOUT GETTING OFF THE WATER IN HIGH TEMP HIGH HUMIDITY WITH FAT ASSES ABOARD
iggy:
CHESTER I WAS NOT LOOKING TO CHANGE THE JUGS .BUT TO CHANGE THE WHOLE MOTOR AND WAS HOPING THE 717 HAD THE SAME PTO BOLT PATTERN AS THE 582 SO I COULD USE MY ALL IMPORTANT GEAR REDUCTION AND HAVE A MOTOR WITH ANOTHER 20 MORE HORSEPOWER .IT'S NOT ABOUT SPEED IT'S ABOUT GETTING OFF THE WATER IN HIGH TEMP HIGH HUMIDITY WITH FAT ASSES ABOARD
iggy:
