I've recently replaced the govenor spring on my '78/'79 C30's Yanmar single cylinder YSM 12horse motor. The new spring lead to a HUGE jump in engine preformance. The boats top speed has jumped from 5.5 - 6.5 knots to 6.5- 7.5 knots. I know its riduculous to say that a 3 dollars spring can make such a difference. Alas, man MUST except the good with the bad, and the additonal power has lead to and increase in engine heat. Which in turn is leading me to the water pump and cooling systems: Q: What is the top speed i should expect from this type of engine on a C30? Q: What type of water flow should I see from the exhaust when underway and at idol? (I currently have spurts spaced 1-3 seconds apart. Q: There seems to be a faint stream of steam coming from the exhaust. Is that uncommon? Q: Should I expect to always have heat issues if the engine is ran "wide open"? Any help is appreciated. Jax
Top Speed / Engine Heat
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I've recently replaced the govenor spring on my '78/'79 C30's Yanmar single cylinder YSM 12horse motor. The new spring lead to a HUGE jump in engine preformance. The boats top speed has jumped from 5.5 - 6.5 knots to 6.5- 7.5 knots. I know its riduculous to say that a 3 dollars spring can make such a difference. Alas, man MUST except the good with the bad, and the additonal power has lead to and increase in engine heat. Which in turn is leading me to the water pump and cooling systems: Q: What is the top speed i should expect from this type of engine on a C30? Q: What type of water flow should I see from the exhaust when underway and at idol? (I currently have spurts spaced 1-3 seconds apart. Q: There seems to be a faint stream of steam coming from the exhaust. Is that uncommon? Q: Should I expect to always have heat issues if the engine is ran "wide open"? Any help is appreciated. Jax
Quick thought
Are you pretty sure the impeller is not starting to come apart? A lot of those descriptions are pretty good signs.
Are you pretty sure the impeller is not starting to come apart? A lot of those descriptions are pretty good signs.
Quick thought
Are you pretty sure the impeller is not starting to come apart? A lot of those descriptions are pretty good signs.
Are you pretty sure the impeller is not starting to come apart? A lot of those descriptions are pretty good signs.
Impeller
The trouble could very well be the impeller. I am finding water "seepage" from the water pump. I plan to have the water pump rebuilt or replace this or next week. I am most concerned that there is a blockage in the water line. Jax
The trouble could very well be the impeller. I am finding water "seepage" from the water pump. I plan to have the water pump rebuilt or replace this or next week. I am most concerned that there is a blockage in the water line. Jax
Impeller
The trouble could very well be the impeller. I am finding water "seepage" from the water pump. I plan to have the water pump rebuilt or replace this or next week. I am most concerned that there is a blockage in the water line. Jax
The trouble could very well be the impeller. I am finding water "seepage" from the water pump. I plan to have the water pump rebuilt or replace this or next week. I am most concerned that there is a blockage in the water line. Jax
Exhaust riser
You might check the exhaust riser. I started my engine (Universal 11 hp) this season to experience some overheating and reduced water flow. After checking the impeller etc, pulled the riser and found it clogged so little water was injected. As you poke around this is another alternative.
You might check the exhaust riser. I started my engine (Universal 11 hp) this season to experience some overheating and reduced water flow. After checking the impeller etc, pulled the riser and found it clogged so little water was injected. As you poke around this is another alternative.
Exhaust riser
You might check the exhaust riser. I started my engine (Universal 11 hp) this season to experience some overheating and reduced water flow. After checking the impeller etc, pulled the riser and found it clogged so little water was injected. As you poke around this is another alternative.
You might check the exhaust riser. I started my engine (Universal 11 hp) this season to experience some overheating and reduced water flow. After checking the impeller etc, pulled the riser and found it clogged so little water was injected. As you poke around this is another alternative.
Top Speed
Hull speed for the C30 is 6.7 knots. If you are actually exceeding this speed by a full knot that could be some of your heating up problem. Are you exceeding the RPM limits of the engine?
Hull speed for the C30 is 6.7 knots. If you are actually exceeding this speed by a full knot that could be some of your heating up problem. Are you exceeding the RPM limits of the engine?
Top Speed
Hull speed for the C30 is 6.7 knots. If you are actually exceeding this speed by a full knot that could be some of your heating up problem. Are you exceeding the RPM limits of the engine?
Hull speed for the C30 is 6.7 knots. If you are actually exceeding this speed by a full knot that could be some of your heating up problem. Are you exceeding the RPM limits of the engine?
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