benjilafouine
Well-Known Member
What is the difference between a Rotax 717 and 720 engine?
Thanks.
Benji.
Thanks.
Benji.
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717 vs 720 engine
- Thread starter benjilafouine
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clmboating
Member
The numbers after represent "CC".
benjilafouine
Well-Known Member
So we have to assume that these engines are slightly different?
glsmohio
Well-Known Member
Your right on there....same motor...the only difference is if there is a "x" after it. Not sure if there even is a 720x motor tho. I know there is a 787x and a 657x.
benjilafouine
Well-Known Member
My ski broke down and the dealer ordered a rebuilt motor from BRP. Still not sure but the new motor was slightly different from the original (subtle differences). And the rotary valve was set for a 717. Now they suspect that they got a 720 instead and that there may be differences after all. The ski is running bad so they are now trying to understand the differences. But this is not confirmed. This is why I was asking.
Benji.
Benji.
glsmohio
Well-Known Member
Keep me posted on what comes out of this. Could be a lot of things why it's running bad. Not knowing your symptoms it's hard to say.
benjilafouine
Well-Known Member
You can see the symptoms there: http://www.seadooforum.com/showthre...sue-with-rebuilding-a-2003-GTI-LE-single-carb
I am so much at a complete lost... and my wallet is bleeding bad.
Benji
I am so much at a complete lost... and my wallet is bleeding bad.
Benji
Benji a "dealership" :facepalm: that does not know that a 717 and a 720 are the same thing is no place to take the ski and open your wallet. That single carb 717(720) is a very simple engine and the right guy would go right to the issue and solve it. They are gonna just want to try replacing things at your expense until they stumble across the problem by process of elimination. Be firm with them and chop that bill down to the part of it you actually needed. It just hurts to see a member get soaked by a clueless shop.
benjilafouine
Well-Known Member
Actually, the story is a bit different. They are scratching their heads with the problem and they noticed last night that there were subtle differences between the old engine and the rebuilt one. So they are searching what is wrong and they might even replace the engine again if it proves to be defective.
I don't think they will bleed me more for that as they seem to have accepted responsibility (warranty that came with the job). They have also looked at the rotary valve to see if the adjustment is the same.
Basically, a 717 and a 720 should be the same thing but the motor they got back has slight differences. I know nothing about this but they said the motor had "two pulse" rather than one and that one pulse was deactivated. My motor had only one pulse.
This is why I was asking the question.
Benji
I don't think they will bleed me more for that as they seem to have accepted responsibility (warranty that came with the job). They have also looked at the rotary valve to see if the adjustment is the same.
Basically, a 717 and a 720 should be the same thing but the motor they got back has slight differences. I know nothing about this but they said the motor had "two pulse" rather than one and that one pulse was deactivated. My motor had only one pulse.
This is why I was asking the question.
Benji
bush
New Member
The boats have the pulse line on the other side of the motor compared to the pwc in my experience.
Brp is probably just making one replacement for both.
I sorta understand the dealers issues. My dealership won't even work on anything older than 7 years because the techs just don't know them. Sometimes the local shops are better for older tech than a dealer.
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Brp is probably just making one replacement for both.
I sorta understand the dealers issues. My dealership won't even work on anything older than 7 years because the techs just don't know them. Sometimes the local shops are better for older tech than a dealer.
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benjilafouine
Well-Known Member
They have two top (older) techs. Now both are working on it. And as you mention, they don't like to work on older machines like if they were tossing out their most faithful clients with older stuff. We had a discussion (a bit heated) on that yesterday and at least some employees think that BRP should stick more to its old stuff.
There are lots of 2-stroke ski-doo's left out there and they must understand that you can't just leave a client like that on his own. I own a Ford Focus 2003 SE Sport, standard transmission, in super shape (doesn't run in the winter anymore for several years) and I still go to Ford for major repairs. Imagine if they would start telling me to go somewhere else.
So it is confirmed that the motor seems a bit different than the original (as it came with two pulse lines instead of one). Now they have to find if all specs match (timing, carb, etc.). And if everything matches, it could be the new motor itself not being sealed properly. For that, they told me they would have to take it out of the ski and test it (worse case scenario).
The engine is under warranty but this is a huge loss of time.
Benji.
There are lots of 2-stroke ski-doo's left out there and they must understand that you can't just leave a client like that on his own. I own a Ford Focus 2003 SE Sport, standard transmission, in super shape (doesn't run in the winter anymore for several years) and I still go to Ford for major repairs. Imagine if they would start telling me to go somewhere else.
So it is confirmed that the motor seems a bit different than the original (as it came with two pulse lines instead of one). Now they have to find if all specs match (timing, carb, etc.). And if everything matches, it could be the new motor itself not being sealed properly. For that, they told me they would have to take it out of the ski and test it (worse case scenario).
The engine is under warranty but this is a huge loss of time.
Benji.
bush
New Member
In the skidoo world we test for leaks in the machine if it runs... Just spray ether or carb cleaner around the suspect leak zones while it idles. If the idle raises you know there is a leak.
Of course there is no substitute for a true leak test.
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Of course there is no substitute for a true leak test.
Sent from my SGH-I747M using Tapatalk
benjilafouine
Well-Known Member
I know. It has been dragging for more than three weeks. In total, my ski has been broken for one month. Lost almost half of the summer.
Benji.
Benji.
To clear up the 717 vs. 720 issue as Matt eluded to they are the same engine. The actual displacement is 717 cc and for whatever reason seadoo rounded up to 720 cc for advertising. Just like they called the 787 a 800 class engine. The only differences was that the single carb ones have a pulse line on the front of the side of the intake manifold area and the twin carb ones have the pulse line on the rear or vise versa, can't remember. When they are rebuilt I am sure seadoo just sends one with both pulse lines open and plugs the ones not needed.
It the old guys at the shop don't know that the 717 and 720 are the same they shouldn't be working on it. They also should be doing a proper leak down test on any engine before it goes back into the ski, even a fresh one from BRP since it doesn't come with the head and should be checked.
I still say you have a carb issue like in your original thread.
Also what is the compression on the new engine?
It the old guys at the shop don't know that the 717 and 720 are the same they shouldn't be working on it. They also should be doing a proper leak down test on any engine before it goes back into the ski, even a fresh one from BRP since it doesn't come with the head and should be checked.
I still say you have a carb issue like in your original thread.
Also what is the compression on the new engine?
benjilafouine
Well-Known Member
They never said that they didn't know if there was a difference between the two engines. I am the one who asked it! However, the engine was slightly different to start with these two pulses rather than one.
I should have more information later today but I am prepared to spend my fifth week without my ski (except for three days where it ran with this issue so I could not go anywhere far from my home).
Benji.
I should have more information later today but I am prepared to spend my fifth week without my ski (except for three days where it ran with this issue so I could not go anywhere far from my home).
Benji.
reedsposer22
New Member
I am confused now on this thread. so is 717 the exact same thing as 720? I have a 717 motor per the ID number on top of the magneto housing. Thanks for clarifiying
If you guys want me to combine the threads I can do that. I know I have suggested one thread to other guys before and caught heck for it from the poster(not you Benji), but one ski, one thread for me makes a ton of sense (for me) and easy for everyone participating to help out. But for now just carry on guys and try and help Benji out. To me the dealer sounds shifty.
benjilafouine
Well-Known Member
Yeah, this thread was only intended to shed light on people using 720 and other people using 717 to describe the same engine and it has been answered in this thread. I have another carb thread but this was solved as well although I was ripped 1,000.00$ by the dealer... I still have a compression question pending in my winterizing/battery thread and then I am all done for this year!!!
Benji.
Benji.
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