Newbee With Couple Question

[snoopy'sbitch]

Hey everyone, new to this forum, and its great. I just aquired a 96 sl 780 with no compression in last cylinder. I got used jug and piston and gasket kit from ebay, and got it running great. Now I want it 100% right cause I'm a nut. First off, any idea why one cylinder would crap out on me, and not the others. The guy I got it free from said he ran out of oil cause mfd didnt work, so he wasnt warned. Any issues with oil pump? i wonder if he really ran out of oil. After putting engine back together, i mixed the oil and gas just in case 2 stroke oil wasnt getting to last carb. So my questions are should I get rid of oil pump all together, or are those pumps built to last, and I should just repalce all the oil lines. Question 2 is does anyone have a good mfd. I checked fuse and its good. Display came on once, and the next day it was all over with. Can they be repaired? And last question is the trim motor. Can they be taken apart and fixed. Mine doesnt move and all wiring checks out. Power and ground go to motor, but she no move. Thanks for all your help.

[xlint89]

Welcome to the Hulk bitch!!!

For preventative maintanence, I'd do the oil block off. The oil pumps are a good design, but any failure will result in catastrophic failure.
If you keep it, change the oil lines for sure.

MFD are out there, but you can fix them. There's a thread on how to do it in the tech section. But first, try removing the connector from the back of it, clean and re-install it. Sometimes the pins don't make good contact.

Yes the trim motor can be fixed. You can open it up and service and/or replace the motor only. Usually it rusts, but you can clean it and it will come back to life.

[seaobin]

Xlint89 Please play nice with the noobie, at least until he is hooked on Watcon and Amsoil

Oh yeah, as for your ski WHAT HE SAID!

[ph2ocraft]

I'd also like to say WELCOME tothe Green Hulk Forums!!!

[xlint89]

Xlint89 Please play nice with the noobie

What? It's his shortened screen name...

[snoopy'sbitch]

Haha, you can bust my chops. I'm easy going. thanks for the good info. Is there a good website to get a block off, and has anyone ever tried to use the oil tank as an extra holding tank for the gas. Extra riding time would be great and what better place to hold more gas then an oil tank thats not being used.

[xlint89]

Just having fun with you, no offense at all.

Many places to score parts from. First comprise a list of ALL the parts you'll need. Being a 12 yr old ski, it's not a bad idea to replace/update the fuel system as that's the weakest link on these ski. (And possibly your original piston failure problem)

At the very least, you should get new fuel hoses (16' or so)
The oil pump block off plate
And possibly 3 Mikunin SBN 38mm carb rebuild kits. If you don't buy the kits, at the very least, thoroughly clean and inspect the carbs. There's a filter internally that may need cleaned.

[snoopy'sbitch]

Well, i believe i need a good mfd. I'm sure i can fix the trim motor, and i can replace all the lines. Now, can i use the oil tank for more gas, adn what websites are geared towards polaris parts for the blockoff. And when i premix should I be at 32:1 or so. I want good lubrication(thats what she said) to make sure this thing doesnt run lean on the oil, and not to much it kills performance. Any idea horsepower on a stocker, and speed i should get balls to the wall

[xlint89]

Some guys do use the oil tank as a reserve fuel tank. I think there's an issue with venting though.

Premix should run 32:1 at break in. Other than that 40:1 is recommended.

HP on a 780 is advertised as 92+ which should run you around 52-53 MPH ish? stock.

Best places for parts are Watcon.com, atlanticpowersports.com, atlanticjetsports.com, denniskirk.com, parkeryamaha.com, partsland.com. babbitsonline.com, and as always EBAY...

[snoopy'sbitch]

Thanks alot for the great info. i'll check out those websites. 52 mph sounds a bit slow for 90 horse, doesnt it. anyhow time to pull trim out and see if i can get it working again