Yesterday I had to re-winterize my 2001 Yanmar 2GM because of a hard freeze. The engine must have a high heating threshold because it took 20 minutes of idle and 20 minutes of 2000 RPM to get the pickup line to take in raw water.
I have a T-valve installed after the jar to pour the antifreeze in by funnel. As before, the antifreeze doesn’t go in readily, yet the engine continues to perk along.
I experimented by opening the raw water valve halfway, and sure enough the anti-freeze went in, albeit diluted further.
This raises several questions.
1. How can engine run 40 minutes without sucking in raw water?
2. Why doesn’t the anti-freeze go in once the engine is warm?
3. Could it be that my anti-freeze was going out the thru-hull?
Thanks in advance for your advice.
I have a T-valve installed after the jar to pour the antifreeze in by funnel. As before, the antifreeze doesn’t go in readily, yet the engine continues to perk along.
I experimented by opening the raw water valve halfway, and sure enough the anti-freeze went in, albeit diluted further.
This raises several questions.
1. How can engine run 40 minutes without sucking in raw water?
2. Why doesn’t the anti-freeze go in once the engine is warm?
3. Could it be that my anti-freeze was going out the thru-hull?
Thanks in advance for your advice.
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