Top End Rebuild- Need an experienced evaluation!!

[Khammy87]

Hey guys,

Well, with the 130psi compression on my cylinders, I decided it would be a good idea to rebuild this thing. Taking it apart was A LOT easier than I anticipated. I guess getting it back together will be the challenge! Haha. Anyways, I took pictures along the way, and would like someone to evaluate these for me and give me their opinion on what should be done. Also, the cylinder bolts into the crankcase had no kind of consistency on tightness- Is this normal? Shouldn't they have been torqued to a certain amount?

Thanks for the input everyone!!

http://s77.photobucket.com/albums/j79/kellenthemage/1994%20SeaDoo/

 

[boattechguy]

time for a top end rebuild. the rear piston shows signs of scuffing due to heat and or lack of lube. buy a topend end kit (sbt or wsm platinum) and have cylinders bore to fit them. as for the torque go by the book and torque all the bolts to spec and in the manual it will tell u where to use loctite. also another helpful word is to find why u got the lack of lube. check all oil lines and then go through the carbs to ensure u dont damage a new set of pistons due to a lean condition. also try to pull the motor as it will aid u in removing the carbs and checking out the tiny oil lines feeding the engine. dont skimp on the kit and dont buy a wiseco kit as it will cause u problems with a possible cold siezure .

 

[Khammy87]

I figured as much. I just rebuilt the carbs in hopes of that being my problem. I don't want to remove this engine if I don't have to.

I've contemplating on bypassing the oil pump and just mixing my own gas, thoughts?

 

[seadoodoopartsofcf]

Do it!!:agree:

 

[Khammy87]

Alright, I was told to do 16:1 for break in, 32:1 for normal, is that correct? Also, do I need to do anything special with the oil pump and such? Cap it off? Can I remove that reserve tank?

 

[El Toro 33809]

The Seadoo oil pumps are very reliable. If the cable fails they will put in too much oil from going to the full-on position. I believe that 40:1 is the proper ratio if you do remove the pump. There is a block off plate available, but you will still need the oil tank and some oil since it lubes the rotary valve shaft.

 

[Khammy87]

Hmm, then perhaps I will keep it lol

 

[brock1]

just test the pump and check its output....mixing sucks ....i went premix for about 2 weeks and it was such an inconvience to me...remove the pump and the white gear and hook the shaft to a drill and spin it counterclockwise and measue the oil output,,,your manual will tell you what it is supposed to be

 

[seadoodoopartsofcf]

Sometimes peace of mind is something worth a little extra work when it comes time to premix gas. Besides it's a better alternative due to having more control over what amount of oil your jet ski consumes...Think about it...your relying on a mechanical part to never go bad...not to mention having to buy a inline oil filter, the bottoms of the tanks have rubber grommets that leak and go bad...if this is something that has not happened to you then you may take the high road and think that the pumps will last a lifetime...good luck with that.

 

[brock1]

think of it this way though....if you run 40:1 then your running basically the same mixture that the pump runs at wide open...so that means even at idle your ski is running too much oil and will load up...and as far as the gromets on the tank...oh well you need the tank in there anyways to lube the RV so if the gromet goes bad you still gotta replace it...... an inline oil filter is about 10 bucks and 30 seconds to install.............when you say having better control of how much oil your ski consumes..I will GUARANTEE you that if you premix your gas in a 800 and i ran my oil pump i promise you that after a day of riding you will have used more oil than me

 

[seadoodoopartsofcf]

Who says I run 40:1? Thats a good mix for breakin period. 50:1 is what I typically run. And you don't need the tank in there to lube the rotax shaft. We run a looped oil line with an oil fill with clear hose. All about preferences seems like too many on here have jumped on the non premix gas bandwagon...just my opinion though.

 

[Seadoobuddy]

Sometimes peace of mind is something worth a little extra work when it comes time to premix gas. Besides it's a better alternative due to having more control over what amount of oil your jet ski consumes...Think about it...your relying on a mechanical part to never go bad...not to mention having to buy a inline oil filter, the bottoms of the tanks have rubber grommets that leak and go bad...if this is something that has not happened to you then you may take the high road and think that the pumps will last a lifetime...good luck with that.

You still need the tank and bottom grommets EVEN if you go premix.
Plus with injection you use less oil....with premix you use 40:1 all the time. With the pump you use 100:1 at idle then go up from there probably to about 40 or 30:1 at WOT


PS, I didn't see Brock's post or your reply when i posted this. I vote oil injection. Just my HO.

 

[seadoodoopartsofcf]

I knew this was s sticky subject when I replied...almost like rutting for the Packers in the New England section of the stadium...your just not going to get a warm reception...

 

[Khammy87]

Haha, well, I guess it's just personal preference for the pump.. I'm still in the air about it and I suppose that I will have to make a decision with enough research and time. Thanks all! Any other input is appreciated!

 

[racerxxx]

In my 99 Speedster I ate 3 MAG pistons. The previous 2 guys who rebuilt the engine for me probably never pressure tested the the engine. So that's when I lost all trust in anyone but myself to work on my boat. When I rebuilt the engine I found the air leak----but just to be sure it wasn't an oil supply issue I ditched the oil pumps on both engines and never looked back. Premix is so easy a cave man could do it. I pull up to the pump tank up to an even gallon amount, then get out my fancy ratio bottle that I bought for about $8, pour my oil in to X gallons(I usually have to multiply since the bottle isn't big enough to hit 30 gallons of gas) then dump it into the tank. Now I know for sure I have the oil in there. $5 in plugs is cheaper then rebuiling a 787. I go thru tons of no wake zones for 5-10 minutes at a clip, I might get a bog but once the throttles are pasted at 7K I never know the difference. Haven't fouled a plug in a few years since converting. Now on the 96 XP I'm redoing I'm on the fence to inject or premix, probably pre mix. If I do a complete fill up in the Speedster 40 gallons and 1 gallon of XPS-II I'm tipping the scale at $200+ for a fill up--not cheap, but again--I know the oils in there. It's all personal preference, and the sky is green in my world!

 

[ocod]

In my 99 Speedster I ate 3 MAG pistons. The previous 2 guys who rebuilt the engine for me probably never pressure tested the the engine. So that's when I lost all trust in anyone but myself to work on my boat. When I rebuilt the engine I found the air leak----but just to be sure it wasn't an oil supply issue I ditched the oil pumps on both engines and never looked back. Premix is so easy a cave man could do it. I pull up to the pump tank up to an even gallon amount, then get out my fancy ratio bottle that I bought for about $8, pour my oil in to X gallons(I usually have to multiply since the bottle isn't big enough to hit 30 gallons of gas) then dump it into the tank. Now I know for sure I have the oil in there. $5 in plugs is cheaper then rebuiling a 787. I go thru tons of no wake zones for 5-10 minutes at a clip, I might get a bog but once the throttles are pasted at 7K I never know the difference. Haven't fouled a plug in a few years since converting. Now on the 96 XP I'm redoing I'm on the fence to inject or premix, probably pre mix. If I do a complete fill up in the Speedster 40 gallons and 1 gallon of XPS-II I'm tipping the scale at $200+ for a fill up--not cheap, but again--I know the oils in there. It's all personal preference, and the sky is green in my world!

Its more complicated w/9 gallon tank.
I stopped adding oil to tank thinking it only needs 5 gallons and it be short one.
I just take 2 x 5 gallon jugs and mix the 16oz. Then any thing left I put into a spare 2 gallon tank and take it with me in the bin.


edit: I support premix and so does buckwheat

 

[seadoodoopartsofcf]

Man..I'm likin' the new avatar... O'tay

 

[ocod]

Man..I'm likin' the new avatar... O'tay

Heyyyyyyy,

Can't be to mad I stole my avatar

 

[Khammy87]

Alright, so I am pretty much sold on going to pre-mix. It's not that hard to throw oil into the gas, and you know for sure it's there. So what if it bog it a little when getting out of the no-wake? It's better than starving it for oil and screwing up your freshly rebuilt machine. That being said, is there a good thread you guys recommend on how to make the conversion??

 

[ocod]

1.Take off intake by 4 bolts. Carb may have to come to make handling easier. Leave linkage connected
2.Then the 6 or 8 hex bolts on carb intake
3. Remove nut holding nylon gear
4. Remove two hex bolts holding pump.
5. Install block off in now open space of intake
6. Reassemble
7. Leave big line w/o filter attached to feed rotary valve.

That should be it.

Premix at 40:1

 

[racerxxx]

Not trying to throw gas onto the fire but here is the bottle I use,for other to see. On the 40:1 ratio it goes up to 8.5 gallons, so you just fill it to the line according to how many gallons of gas you just pumped it--straight forward, no math. If you run 50:1 just rotate the bottle to the right and follow that 50:1 gallon graduation. Like I said I always fill to an even gallon or half, I always watch how full my tank gets visually anyway, don't want any spillage. It's a SeaSense 2-Cycle Oil Mixing Measurement Bottle 50091443 can be bought at most boat dealers, overtons, ebay, amazon, etc...

 

[Khammy87]

Well that seems easy.. Lol.. Now since that line has to be there anyways for the RV.. How often does that tank have to be filled, typically?

 

[Khammy87]

Also, thoughts on what ratio should be run for my break-in period? For how long? Can I go full-throttle and rip the hell out of this thing immediately?

 

[ocod]

Not trying to throw gas onto the fire but here is the bottle I use,for other to see. On the 40:1 ratio it goes up to 8.5 gallons, so you just fill it to the line according to how many gallons of gas you just pumped it--straight forward, no math. If you run 50:1 just rotate the bottle to the right and follow that 50:1 gallon graduation.

That definitely makes measuring easy especially with odd number of gallons pumped.
Just add oil to right level.
Better than other types of measuring cups I've seen.

Ingenuous!

 

[racerxxx]

That tank will stay at what ever level you fill it to--just keep an eye on it. If you were to blow a crank seal it would start to use the oil, or if a line were to pop off and drain out.

I'd break it in at 40:1 and just cruise around with varying throttle speed for about a half tank of gas(never full throttle, then after that the world is your oyster. On my new skis in 96 I ran thru half a tank and then had at it, never had one issue with those ski's.