-
This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.
787 rebuilt motor not going over 4000rpms
- Thread starter irish88
- Start date
- Status
Smoking...?
Is it smoking? When you do break-in, you really should not be trying to hit max RPM anyway. After a few hours on the motor, you can goose it, take it wide open throttle, then back it back down.
But, even now, you should be able to hit 7200 rpm. Like above, I just would not recommend doing it for a few hours.
The timing in the 787cc engine is pretty much preset. You bolt it on and it's ready to go. The rotary valve on the other hand, works similar to timing. When you did the rebuild, are you sure you put the rotary valve on correctly. This valve plate is not asymetrical. There is a front side and back side. If you line it up on the wrong side, it will be off by 1/2 tooth, per se. Flip it over and it will be exact on your degree wheel's marks.
Check your compression, check your RAVE valves. If you are only goosing it and it's bogging at 4k, it could very well be the RAVE valves. The manual says to run them down but there was a supplement that came out a bit later that said to run the red adjustment cap even to the rim of the black cap. If you have to much spring tension on the slide valve, it may be trying to stick closed on you.
I would def do a compression test, since you just did a rebuild. Check the RAVE valves and if all is good, you might think about your rotary valve plate.
Balance shaft oil? Did you put the 1oz of oil in your balance shaft on rebuild?:cheers:
Is it smoking? When you do break-in, you really should not be trying to hit max RPM anyway. After a few hours on the motor, you can goose it, take it wide open throttle, then back it back down.
But, even now, you should be able to hit 7200 rpm. Like above, I just would not recommend doing it for a few hours.
The timing in the 787cc engine is pretty much preset. You bolt it on and it's ready to go. The rotary valve on the other hand, works similar to timing. When you did the rebuild, are you sure you put the rotary valve on correctly. This valve plate is not asymetrical. There is a front side and back side. If you line it up on the wrong side, it will be off by 1/2 tooth, per se. Flip it over and it will be exact on your degree wheel's marks.
Check your compression, check your RAVE valves. If you are only goosing it and it's bogging at 4k, it could very well be the RAVE valves. The manual says to run them down but there was a supplement that came out a bit later that said to run the red adjustment cap even to the rim of the black cap. If you have to much spring tension on the slide valve, it may be trying to stick closed on you.
I would def do a compression test, since you just did a rebuild. Check the RAVE valves and if all is good, you might think about your rotary valve plate.
Balance shaft oil? Did you put the 1oz of oil in your balance shaft on rebuild?:cheers:
- Status
