Hello, I have been working on my 37c that has yet to go into the water since I bought it. It was originally Jolly Roger in Melbourne Florida. Anyway, I am in Green Cove Springs North Florida and almost immediately upon putting her in the water I must get to Brevard County. The boat is equipped with the 3qm30 and a three-blade prop. I'm wondering what a reasonable cruising speed is so I can plot fuel and time. I don't want to run it as fast as possible but I don't want four knots either. Can someone give me a reasonable idea, not pushing the motor too hard, what kind of speed I should be able to make in calm water? Thanks much!
37c motoring speed
- Thread starter Cocoa Beach Sailor
- Start date
On my old H37 with a 3QM30 and a two-blade Michigan Wheel prop, I used to make about 6.5 knots at approximately 2200 RPM. That seemed to be the sweet spot for me. Speed went down by up to a knot with opposing wind and seas or a dirty bottom.
Agree with Jim. My experience is 7 statute miles per hour at less than 0.7 gallons of diesel per hour.
if you are going to motor “hard” for some hours on end it is essential to ensure that the raw water system is in good shape. This is intake strainer pump heat exchanger exhaust manifold and mixing elbow.
if you are going to motor “hard” for some hours on end it is essential to ensure that the raw water system is in good shape. This is intake strainer pump heat exchanger exhaust manifold and mixing elbow.
Thanks much! I was planning on 6.5 statute miles per hour with a brand new clean bottom and little to no wind. Hopefully it will be windy and I can shut the silly motor off and go out offshore and sail down but as a backup I've got to figure out my motoring situation. It is been Dead Calm for 4 days. It would really be irritating to have to motor 150 Mi or so after having put so much time and money into this boat! One other question, assume a beam reach, what kind of wind speeds would I need to hit six and a half miles per hour or I guess that would be 5 and 3/4 knots or so. Assume stretched out sales that someone who can trim pretty decently, not a pathological string puller but pretty close
I forget where I am on that subject. I have read so many different things about the subject. Unfortunately most people talk about what engine they have, which is not relevant. It is about the transmission. I have a zf45-1 which I believe is better left in reverse.
Neutral is never a bad decision. Some transmissions tolerate reverse, and your Hurth might be among them, but that’s more drag than neutral anyway.
On the subject of not wanting to push the engine too hard - most marine diesels recommend running around 80% of full power continuously. Counterintuitively running them too gently causes more problems by allowing carbon buildup instead of keeping everything hot enough to stay clean.