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  1. #1

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    coverting a slt750 fugi engine to a 780 (help)

    I was looking for some info on converting a 750 engine to a 780? I was told you could swap over the cylinders & pistons & it would work. If that's the case can you use the old carb off the 750 & adjust it to the 780 cylinders & is the exhaust manifold the same. any help would be great thanks.....


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    780 cylinders and heads, exhaust manifold with bolts, rejet the carbs to 780 specs or just buy 780 carbs, 780 CDI (not totally necessary, but recommended) and a 780 impeller would be what's needed

  3. #3

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    Is the pump config the same? Is there a wedge on the 780 pump? I just picked up a 96 slt 780 running excellent, very well maintained. Was just wondering the same...whats different between the 95 slt 750 complete vs. the 96 slt 780 complete machine?(other than previuosly stated)
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  4. #4
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    The 95 SLT 750 is a fibreglass hull, so it's actually a little lighter than the 780.

    The 780 makes 90+ HP while the 750 makes 80 HP

    The 780 has the extended jet pump while the 750 uses the short pump. (the additional parts can be added to make it a long pump, however it sticks quite a bit out of the back while the 780 is tucked under the boat more.)

    Some people claim the 750 porting is better on the bottom end and the 780 has a hard 2 stroke "hit". Not as easy to just cruise, it wants to run WOT.

    The 750 will do around 48 MPH and the 780 runs close to 52 MPH

    Lastly, the SLT 780 and SLTX hulls (they share the same design) seem to have a problem with cracking on the right hand side near the middle when ridden hard in rough waters. Our personal experience has encountered 3 cracked SLTX (all 3 right side in the middle below the rub rail) and the 780 is cracking on the right in the middle just above the rub rail.

    The 750 with the fibreglass hull is only showing signs of gelcoat cracking. The hull is solid even though it gets the same abuse as the others.

  5. #5

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    All good info thanks so much!. I have gelcoat cracking on the slt 750 right hand side top deck middle just above where your ankle would be when sitting...on the top of the footwell radius...not a big issue, been there for years. I am surprised that the 750 is heavier...assumed the fiberglass and gelcoat would be denser than the smc hull...wow! With that extended jet pump my dog will have a heyday...she tries to eat the jet everytime it is started....it's a little worrisome as we must endeavour to avoid sucking in her tail!
    A qwik question....can I reuse head gaskets after checking piston wash?...or is the borescope/endoscope method sufficient so that head removal is not required?

  6. #6
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    The 750 is lighter then the 780, not the other way around.

    Head gaskets can be re-used if you spray them with Permatex copper sealer. (not recommended, but many of us do it all the time)

    Using a bore scope or small flex light is usually good enough to view piston wash. Just make sure the piston you want to view is all the way at the bottom and you can see almost all the piston dome.

  7. #7

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    Ok thx...guess I will pickup some of that spray from NAPA just incase. I won't be able to use the endoscope until Saturday so I will report back with my findings then.

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