jslu
Seaman
- Joined
- Jul 31, 2010
- Messages
- 74
1987 merc 35hp SN 0b177575, which I've had for 2 years now.
I've been wondering about this for some time.
Why did Merc elect not to install a thermostat for this engine???. A part #.is not listed for one.
To me it makes sense that a gasoline engine has an optimum temp operatimg range for best performance.
I live in Maine and my boating/fishing season starts early at ice out, trolling for salmon. water temp around 35 to 45 F.
This engine does not like to be fed water that cold.
Similarly, years ago, I purchased a brand new, right out of the crate, 1970 Johnson 60 Hp which at initial shakedown cruise was also a poor performer in cold water. Then, as now, I suspected thermostat problems. When I removed the thermostat housing cover, I was amazed to find that either by design or assembly screw-up, a thermostat was not installed. This thermostat had a part #. and after installing it, the lack of cold water performance went away. That engine gave me good service for 39 years and is still running today.
Now back to the Merc. I realize the enriching the low speed idle jet might help, but not easy to do with a long screwdriver and a pitching boat. Would be nice if it had an external idle adjust. The problem I've described is also noticeable througout the boating season to a lesser but still annoying degree.
I have located an aftermarket thermostat kit for this engine.
Anyone out there, your thoughts. Would this be a good idea??
Thanks
jslu
I've been wondering about this for some time.
Why did Merc elect not to install a thermostat for this engine???. A part #.is not listed for one.
To me it makes sense that a gasoline engine has an optimum temp operatimg range for best performance.
I live in Maine and my boating/fishing season starts early at ice out, trolling for salmon. water temp around 35 to 45 F.
This engine does not like to be fed water that cold.
Similarly, years ago, I purchased a brand new, right out of the crate, 1970 Johnson 60 Hp which at initial shakedown cruise was also a poor performer in cold water. Then, as now, I suspected thermostat problems. When I removed the thermostat housing cover, I was amazed to find that either by design or assembly screw-up, a thermostat was not installed. This thermostat had a part #. and after installing it, the lack of cold water performance went away. That engine gave me good service for 39 years and is still running today.
Now back to the Merc. I realize the enriching the low speed idle jet might help, but not easy to do with a long screwdriver and a pitching boat. Would be nice if it had an external idle adjust. The problem I've described is also noticeable througout the boating season to a lesser but still annoying degree.
I have located an aftermarket thermostat kit for this engine.
Anyone out there, your thoughts. Would this be a good idea??
Thanks
jslu
