New Motor Going In - Have Question

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desjardins2020

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Ok, so finally got the old sized engine out of the boat and as I though my piston were sized in the jugs it turned out to be the bottom end connecting rod bearing sized up... so I have two questions - as I bought a new engine ( used out of a running machine )

1) is there anything I need to do to this engine when I get it to prep it for install? lube anything?, drop some oil down the spark holes get some oil in there? anything?
2) obviously something happen, the boat sized now could my oil AND cooling system have been working fine but the bearing just failed OR would you suspect that either it wasn't getting oil or water...

I did remove the seat cover when it first stalled on me in the water and touched the exhaust and it was hot - i thought these things run cold due to having water rushing through them? so that made me believe that it wasn't getting water... but mine is oil injected and I don't have clear oil lines so hard to tell if oil pump system is working...

any thoughts and help would be appreciated - I don't want to sieze it again
 
You need to rebuild the carbs and fuel system if this is a carbed ski.
I would change the oil in the balancer if it is a 787.

What ski and engine is it?
 
You mentioned not having clear oil lines, redoing the oil injection lines and a filter would be a must for me in addition to what's stated above for a new motor.
 
1999 Seadoo GTX RFI 787 -

Motor came out of a running machine same model same year same engine. I have to rebuild it??? oil lines yes I was plainning on doing this... balancer is the little hole at the bottom and it;s what 4 oz or something like that? of what 2 stroke oil?
 
1 oz (30 ml) SAE 30w motor oil. Drain from the allan plug on the bottom and fill from the filler cap. Page 02-04-3 of the 1999 service manual.

No carbs to rebuild but I would for sure change the int tank fuel filters.
 
ok fair enough I'll look into that - but regarding the second half the question as to what might have caused this in the first place - can you shed some light on this for me... if that exhaust was hot when it shut down on me and sized would you believe it wasn't getting water... or would this be more floating toward no oil if it was running lien..
 
If it overheated or was out of oil the pistons would be shot too.
The exhaust odes get tot to the touch but it shouldn't burn you.

Blow out all the coolant hoses with compressed air.

Change the oil and filter for peace of mind. Your oil hoses should all be clear, why are they not? What oil are you running?
 
the oil lines look painted - I'll buy some new ones. We were speaking me and you before I showed you a picture of the piston they were toast metal shavings inside when I took heads off.. I attached again here. So with the connecting road sizing and the pistons looking this way what you think happen? I'm changing all the lines and filters to be safe
 

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I would say running lean from lack of fuel. I would suspect the injectors unless you know the oil injection wasn't working.

Make sure you replace the little 3/32" oil lines too. Verify you are using API-TC full synthetic oil and do not premix in an injected ski.
 
A lean engine will run better than it ever has moments before seizing. A lean mixture makes the most power but also more heat and loss of lubrication.
 
The fuel lines are fine and don't blow them out. Just replace all filters. If it was me I would be sending the injectors off to be cleaned and tested. DO NOT buy cheap aftermarket injectors.
 
I'm new to riding and can you tell me something when I get this machine back out on the water and I'm riding what signs am I looking for that I'm running to lien or too rich how do you know this? right now I watch for the pissing in the rear to ensure I'm getting water..

also I've been trying to figure something out - when I setup the garden hose to the port in the rear is this the same place the water comes in when in the lake?
 
The only way you can tell if it is rich or lean is to check the plugs often and there is nothing to tune on an injected ski.

The port on the back is actually back flushing the system so when in the lake water actually comes out of the garden hose hole. Do not block it or leave any adaptors in it. It needs to be fully open.

Also when on the hose the order is very important.
1. Engine on Hose off.
2. Turn hose on, engine on.
3. Turn hose off, engine still on.
4. Turn engine off.
 
So if I'm running too lien the plugs would be black right... this was the plug when I pulled it out... if that relates to lien and there are no adjustments then what is one too do - blow it again?

is it possible this all happen because the bearing in the connecting rod just went and that's that... does it have to be a water intake or oil issue?
 
If it is black or brown it is rich to good. If it is white it is lean. THere is nothing you can do on an injected ski but verify your fuel pressure and injectors are good along with the oil injection system.

Yes it is possible you just had a random crank bearing failure.
 
i'm on the seadoo parts site and trying to find the fuel filter in the schematics can you show me a picture of what it looks like? is there just one?
 
Search here on the forum, there are compatible ones with part numbers for the auto parts store. Search RFI fuel filter.
 
I have a question now that I have the old engine out and I'm waiting for the new one I was hoping to clean the inside - there is alot of oil and dirt and was curious if I was to angle the thing almost upright and spray it down with a pressure washer med pressure is there an issue with that as far as electronics go?
 
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