717 rebuild

[cncsignman]

Will need to rebuild the 717's in my speedster soon. What is the best way to go? Is it better to buy a rebuilt and swap out or rebuild myself? Is there a complete kit available for top and bottom end? Looking for the least expensive way to go.

 

[dcia3231]

What leads you to believe they need a rebuild? have you checked compression? Those 717 engines will last nearly forever. Ive had several with 100's of hours on them. (i install hour meters and run CHEAPO walmart twc3!!! HA premix and oil injection fyi) Who knows how many hours my speedster sk has as the hour meter gave up over winter.

Sbt engines are decent but not always a cost effective solution. The only way you will be able to see wear/tear on those 717 engines is to disassemble them but i would not if the compression is over 120. Once they are apart you can inspect the bottom end. If the rods do not have up/down play or side to side then i would not replace the crank unless it has damage on the rotary valve or other bearings. Rods always have a little play but if they move side to side more than 2 penny's thickness or have up/down play..its time to replace.

Check your compression. Its more important to have similar readings on the same engine than it is to have high compression. If your left engine reads 140/145 then your good. If your right engine reads 120/120 your still good. But if your right engine were to read 120/90 then it needs to be disassembled. Either your carbs are not adjusted properly or your oil injection is not set properly.

Check your compression to start.

Other members can chime in as well.

 

[cncsignman]

Have not checked the compression yet. The guy I bought it from said compression was at 125. I've heard that that is low. The boat runs great and has plenty of power. I will check it this weekend hopefully. Trust me... A rebuild is the last thing I want to do. Thanks for the good advise!!

 

[howie099]

I just go for the rebuild. If you need more than a topend it is the way to go unless it is the middle of the season and don't want an SBT engine rebuild it yourself, but the cost is very close to sending it out. It comes back all pretty, fresh paint, and with a warranty. My 2 engines now are on their way back soon from Fullbore. My boat really didn't need them yet but since they are 18 years old and have about 150 hours on them I got some rebuilt. What I did was buy 2 pretty beatup 1996 GTi's w/717's and sent them off just is case my engines got delayed or I blow one up I can still use my boat. The cost was only $400 for the 2 skis and I will put my working engines back in them and sell them off. Either way the electrical, pumps, and body parts are good so I can make my money back either way.

 

[dcia3231]

Honestly speaking if it runs good don't touch it. I know this has been said 100 times before but "if it aint broke, don't fix it".

125 is fine. I would rent a tester from autozone (if your local az does it) or buy one from harbor freight ( super cheap ) then you can test the compression yourself.

Some people say 125 is low, others say its fine. Is that 125psi with the engine hot or cold? If its cold then your compression will be different hot. The engine needs to warm up 100% to get an accurate reading.

When i had my 1995 seadoo speedster the compression was 110 in all 4 cylinders and it ran great for years. i never once touched it. At the time of sale, i had put 300 hours on it. Engines were original. I took real good care of it. Rebuilt my carbs each year, ran fuel filters, premixed the gas and ran the oil injection.

My current 99' speedster sk has 130psi accross and i do not plan on touching it till one of the engines blows up, starts knocking or gets real hard to start. At which point i will find someone selling a 90's seadoo with a 717 for cheap and pull the engine from it. In my opinion...for the cost of sbt engines it will outweigh the value of the boat. Run the boat till it loses an engine then rebuilt it or find a 90s do with a 657-717 and install it.

 

[hotrodssnova]

Did the previous owner ever do any work on the boat? If so, paperwork to prove? The good news is if one engine dies on the water, you still have the other.
I am getting ready to rebuild my 657x, and parts alone are around 400.00. With a used boat, it's really hard to know the true history. Being miles out and having something go wrong makes for a miserable day.
I have seen top end kits and rebuilt cranks. The top end kits come with the pistons, jugs, and gaskets. The cranks are drop in and that's pretty much all the bottom end is. You can replace the rotary valve shafts if you want cheap enough. That's about all there is to a rebuild.
Do the carbs, and test the oil pump while it's apart.

 

[dcia3231]

Hotrodssnova. Your right thats one of the best parts of having a speedster. They have a "spare" engine! HA

 

[Fat Tony]

I second the fullbore engines, both of mine are from them and have about 70 hours on them now. The PO wasnt much for maintenance from the looks of the boat when I bought it, but both of them read dead on 150 in both cylinders when I checked them at the end of last season.

 

[cncsignman]

Thanks all for the good advise. We took too the water over the weekend and it ran great. For now, I'm going to go with "if it ain't broke don't fix it". Lol

 

[dcia3231]

Check the compression after running it for a day. If the boats been sitting for a few months the compression might go up. When I checked the compression in my speedster last weekend it was low, after running it for an hour it's back to normal. The rings can get a little stuck. The compression is also different when the engines are hot. Like I said, if you blow up an engine find yourself a cheap 717 seadoo and pull the engine from that and drop it in the boat. Cheap replacement. My boats at 443 hours according to the Mpem, all original on this particular model. ( purchased new in 99') I don't plan a rebuild anytime soon.