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Top end rebuild

piper84

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Is it posable to rebuild the top end with eng. In boat LS 2000
 

4x15mph

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Sorry @piper84 , I haven't rebuilt yet but had the same question. Do you have to do 1 engine or can you do both? I would consider a cheap engine lift from harbor freight and pull them out. A lot easier to work on, paint the workbench white so you don't lose parts, and enjoy the fun. Keep me posted and PM me if we can talk through the steps. Great boat!
 

piper84

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Sorry @piper84 , I haven't rebuilt yet but had the same question. Do you have to do 1 engine or can you do both? I would consider a cheap engine lift from harbor freight and pull them out. A lot easier to work on, paint the workbench white so you don't lose parts, and enjoy the fun. Keep me posted and PM me if we can talk through the steps. Great boat!
The. Port eng has a low cyl. So I need to pull the top half inspect and replace what is needed minamum three pistons and have the cyl s. Bored.
 

DCB-270

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You can do it in the boat. It is just uncomfortable to be leaning over for a long time. If you strip most of the stuff off the motor can be lifted by hand.
 

piper84

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You can do it in the boat. It is just uncomfortable to be leaning over for a long time. If you strip most of the stuff off the motor can be lifted by hand.
Good to know that It can be done. Worked on helicopters for 18 years but marine engs. Are a little different. Use to working upside down sometimes! Going to give it a go.
 

DCB-270

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You will be good. It is a very simple motor. Did you find the cause for failure?
 

piper84

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You will be good. It is a very simple motor. Did you find the cause for failure?
Not yet but I bought the boat knowing one eng. Needed some work. I suspect it was an over heat issue. The exhaust riser and water jacket was almost plugged up with scaling restricting water flow. I made sure the motor did turn over, started and ran before l bought the boat. Want to be as less evasive as posable with the job as I can. Will keep you posted.
You will be good. It is a very simple motor. Did you find the cause for failure?
You will be good. It is a very simple motor. Did you find the cause for failure?
 

the MfM

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How low is low?


For me I think I’d rather pull the engine. Doesn’t seem too hard. Be a lot easier working on a bench then going in and out of the boat/engine compartment a hundred times. Less mess etc.

Plus you’ll be easily able to replace the oil lines while one engine is out.
 

boudin

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That's the 1200 NPV motor, and is pretty easy to rebuild with an SBT kit. I would pull the motor, and you'll want to rebuild the carbs as well. Look around in the Yamaha sections on greenhulk.net and you should find lots of help.

-Greg
 

4x15mph

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@piper84 - please take pictures and do a write up! Everyone will thank you for this. Following this thread and can't wait to get started. PM me if I can be of any help - haven't done the rebuild but I have been into the carbs, exhaust, etc.
 

M@__

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Uhhh, don’t get anything but OEM gaskets and quality pistons.

You could do it in the boat, but imagine trying to get three pistons with rings to line up at the same time as you lower the cylinder bank down together ensuring you don’t snag a ring...

If you can imagine how that would work then you won’t be cussing louder than pulling the motor.

I would pull it, but I would replace the crank seals too.

Best luck. Green hulk is the spot just search 65u or gp1200
 

piper84

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I pulled the head off inspected cyl. Walls and tops of pistons. No visible damage our excessive ware. For almost 20 year old motors thay are in good condition. I did note the head bolts came out very easy and the head gasket came off in three peace’s. It delaminates. The gasket may have been leaking compression causing the low compression test. Going to replace it and give it another go. Does anyone know the torque value and torque seaquence of the head bolts? Thank for all info.
 

M@__

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Download the manual for the LS2000. If you cant find that then look for 97 gp1200. Same motor.
 

the MfM

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ADC7F16B-597F-476F-A5A1-A7899B31E38C.png
 

piper84

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Download the manual for the LS2000. If you cant find that then look for 97 gp1200. Same motor.
Thanks did find the link and downloaded the manual. I figured the head had a spasific torque sequence and in few stages.
 

piper84

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Steering cables replaced by connecting the old cable to the new one using a pice of clear tubing and two hose clamps. Was able to pull old cable with new cable trailing. Just a little challenging to make the bend at the aft end. A little
Faness with a broom handle and in it went!
 

the MfM

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Did you take the chance to measure squish?


I haven’t been into mine yet but I recall reading on green hulk that there is some room for improvement. ;)
 

4x15mph

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I also think the torque sequence for the head bolts is printed on the head itself.
 

piper84

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Now that I have the service manual there are a few more things to check befor I reasmeble the Eng. Head worpage can be a couse of low compression our a cracked head as well. There is moderate scaling in the water jacket short of removing the cyl. Case to glass bead it I’m going to try a solushion of CLR to see if it can desolve some of the scaling deposits.
 
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