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Hi,
I have a Yamaha Superjet 701 fitted with a 701 SuperJet Limited pipe. This pipe is great!!!! I have had it on my ski for about 5 years.
I ride my ski in salt water.
Last year I had to rebuild my engine due to water getting across the exhaust manifold gasket and corroding the crank over the winter months. Huge salt deposits were up under the internals of the rear piston. Though the ski went ok. Unbeleivable I know!!! In hindsight, observation of clean plugs would have indicated that salt water was cleaning them.
Obviously due to the cost spent last year, I decided to have a look into the crank as a precaution before winterising by taking of the intake manifold :
OBSERVATIONS:
I observe that the rear web is rusted (tho not heavily) and the front Web is clean. There is no indication that a gasket has broke.
There is no salt in the crank.
When the plugs are removed from the head say ten minutes after riding, the are brown but with little beads of water. The ski starts no prob tho. Is this just condensation from the exhaust.
I am just wondering...
Could this rust be normal i.e due to condensation of water from the exhaust and therefore doing no damage, I.e. SUPERFICIAL RUST. But then why is the rear web exclusively the one with rust? Does the engine always stop exposing the rear exhaust port and hence letting condensation to the rear web in preference to the front one.
Or is the crank to be slightly oily only.
I do flush the ski and this rust that I refer to has happened over the summer months were the ski is rid each week and left to sit for 2 weeks recently.
WHAT HAS CAUSED THE RUST ON 1 of my webs in preference to the other???
Upon removal of head I observe droplets of water on top of pistons. No rust tho. Is this just condensation? How does water get here?
I now know how to winterize ok - 400ml of oil down each plug hole.
I have a Superjet 650cc with the normal Yamaha pipe and its crank is clean.
Is this just a small vulnerability of the FP system that is to be expected and not to worry about due to the obvious intention of the pipe i.e. PERFORMANCE RACING?
Other observations:
Riding the ski fast and shutting off the ignition immediately and observing the plugs indicates nice normal brown colour. This would imply that water is not getting into the combustion chamber this year unlike before.
Can you please advise.
Paul.
I have a Yamaha Superjet 701 fitted with a 701 SuperJet Limited pipe. This pipe is great!!!! I have had it on my ski for about 5 years.
I ride my ski in salt water.
Last year I had to rebuild my engine due to water getting across the exhaust manifold gasket and corroding the crank over the winter months. Huge salt deposits were up under the internals of the rear piston. Though the ski went ok. Unbeleivable I know!!! In hindsight, observation of clean plugs would have indicated that salt water was cleaning them.
Obviously due to the cost spent last year, I decided to have a look into the crank as a precaution before winterising by taking of the intake manifold :
OBSERVATIONS:
I observe that the rear web is rusted (tho not heavily) and the front Web is clean. There is no indication that a gasket has broke.
There is no salt in the crank.
When the plugs are removed from the head say ten minutes after riding, the are brown but with little beads of water. The ski starts no prob tho. Is this just condensation from the exhaust.
I am just wondering...
Could this rust be normal i.e due to condensation of water from the exhaust and therefore doing no damage, I.e. SUPERFICIAL RUST. But then why is the rear web exclusively the one with rust? Does the engine always stop exposing the rear exhaust port and hence letting condensation to the rear web in preference to the front one.
Or is the crank to be slightly oily only.
I do flush the ski and this rust that I refer to has happened over the summer months were the ski is rid each week and left to sit for 2 weeks recently.
WHAT HAS CAUSED THE RUST ON 1 of my webs in preference to the other???
Upon removal of head I observe droplets of water on top of pistons. No rust tho. Is this just condensation? How does water get here?
I now know how to winterize ok - 400ml of oil down each plug hole.
I have a Superjet 650cc with the normal Yamaha pipe and its crank is clean.
Is this just a small vulnerability of the FP system that is to be expected and not to worry about due to the obvious intention of the pipe i.e. PERFORMANCE RACING?
Other observations:
Riding the ski fast and shutting off the ignition immediately and observing the plugs indicates nice normal brown colour. This would imply that water is not getting into the combustion chamber this year unlike before.
Can you please advise.
Paul.
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