I am buying a 1996 Hunter 430. Engine is a 50 HP Volvo Penta. Previous owner changed the original 2 blade proppeller to a 3 blade. Bottom and proppeller is clean. However motoring speed during sea trials at 2,500 RPM was only in the 4,5 - 5 knt range, which I think is a bit too low. What kind of speed do other Hunter 430 owners do at that RPM. I may need a new original 2 blade prop. What dimensions is the shaft??
Hunter 430 motoring speed
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2500 seems low as a cruising rpm.
My Yanmar 56hp on my 2002 Hunter 410 has a max rpm of 3600 according to Yanmar. I understand 80% is a appropriate cruising rpm. Cruising at 80% = about 3000 rpm and I get 7 kts. with a fixed 3 blade prop. Check on the max rating for your engine
My Yanmar 56hp on my 2002 Hunter 410 has a max rpm of 3600 according to Yanmar. I understand 80% is a appropriate cruising rpm. Cruising at 80% = about 3000 rpm and I get 7 kts. with a fixed 3 blade prop. Check on the max rating for your engine
Hi Peter, we have a fixed three blade...
on our 1991 P42 with a 57 HP turbo Yanmar and a 1 and 1/4 inch prop shaft. When I cruise with the engine I normally keep it at 1,800 to 2,000 RPM which pushes the boat at seven to eight knots. The 4JH2TE in our boat has a rated maximum of 4,250 RPM without and around 3,800 under load. Some will say our cruisng RPM is too low. They will claim the lower RPM will glaze the cylinder walls, carbon desposits will build up and all sorts of horrible things will happen. As long as the engine reaches its normal operating temperature, none of these things should happen according to my diesel engine sources. Whether you have a two or three blade prop your engine should be able to push your boat to hull speed, I'm guessing between six and seven knots. If you try a higher RPM, say 3,000, that might get you to hull speed. Terry
on our 1991 P42 with a 57 HP turbo Yanmar and a 1 and 1/4 inch prop shaft. When I cruise with the engine I normally keep it at 1,800 to 2,000 RPM which pushes the boat at seven to eight knots. The 4JH2TE in our boat has a rated maximum of 4,250 RPM without and around 3,800 under load. Some will say our cruisng RPM is too low. They will claim the lower RPM will glaze the cylinder walls, carbon desposits will build up and all sorts of horrible things will happen. As long as the engine reaches its normal operating temperature, none of these things should happen according to my diesel engine sources. Whether you have a two or three blade prop your engine should be able to push your boat to hull speed, I'm guessing between six and seven knots. If you try a higher RPM, say 3,000, that might get you to hull speed. Terry
430 Hull Speed
Our Hunter 430 also has the Volvo engine, but a 2 blade 18" prop. We cruise at 2300 rpm and our speed is 7.3 kts with the dinghy and 7.6 kts without it. Have you checked the knot meter or checked the speed on a GPS? Max rpm for the Volvo MD22L is 3000, recommended max is 2700 rpm. At that rpm we can cruise at 8 kts, but I don't like all the noise. At 2300 rpm its very quiet and smooth. Under sail the boat can easily cruise at 7-8 knots. The shaft size is 1.25 inches. Peter Milne S/V Blue Heron
Our Hunter 430 also has the Volvo engine, but a 2 blade 18" prop. We cruise at 2300 rpm and our speed is 7.3 kts with the dinghy and 7.6 kts without it. Have you checked the knot meter or checked the speed on a GPS? Max rpm for the Volvo MD22L is 3000, recommended max is 2700 rpm. At that rpm we can cruise at 8 kts, but I don't like all the noise. At 2300 rpm its very quiet and smooth. Under sail the boat can easily cruise at 7-8 knots. The shaft size is 1.25 inches. Peter Milne S/V Blue Heron
motoring speed
Peter, were you going against the tide? We have only had our 1995 H430 for a year, but in the SF Bay area sometimes there is a huge difference in our speed depending on tides. The other thing I have noticed is the speed will drop when we are going "up hill" Coming up the coast against wind & waves slowed us down as much as the tide under the Gate. We have the Yanmar 50hp with a three blade feathering prop, and smooth slack water will give us 7.5 to 8+ at 2800 to 3000 rpm. Try running a measured mile in one direction and then reverse course and go back, and check your speeds with a gps also. If you are going that slow see if there is a bucket tied on to the keel before you buy her.
Peter, were you going against the tide? We have only had our 1995 H430 for a year, but in the SF Bay area sometimes there is a huge difference in our speed depending on tides. The other thing I have noticed is the speed will drop when we are going "up hill" Coming up the coast against wind & waves slowed us down as much as the tide under the Gate. We have the Yanmar 50hp with a three blade feathering prop, and smooth slack water will give us 7.5 to 8+ at 2800 to 3000 rpm. Try running a measured mile in one direction and then reverse course and go back, and check your speeds with a gps also. If you are going that slow see if there is a bucket tied on to the keel before you buy her.
A few clarifying questions:
How did you determine your speed of 4.5 - 5 knots? Using a GPS or speedo? If you were using a speedo, is the speedo clean? Could it have a bunch of gunk/growth on the paddle wheel? If you were using a GPS, are you sure it was set to knots, verses KPH, or MPH?
How did you determine your speed of 4.5 - 5 knots? Using a GPS or speedo? If you were using a speedo, is the speedo clean? Could it have a bunch of gunk/growth on the paddle wheel? If you were using a GPS, are you sure it was set to knots, verses KPH, or MPH?
speed update
Went out on the Bay last week-end. At 2900 to 3000 rps we were at +/- 7 knts/hr heading into an incoming tide in the Oakland estuary (not stiff). It looked like we could drop from 3000 to 2550 and only slow down 3/4 of a knt/hr. Out on the Central Bay the tide slowed us down by 1 1/2 knts and more, without really heading into the tide, sort of crossing the Bay. When we got off the City front we turned around and put her at 2600 we were charging along at +/- 8, and my bottom is only so-so on the dirty side. Sure glad I don't have a twin screw fly bridge cruiser to buy fuel for.
Went out on the Bay last week-end. At 2900 to 3000 rps we were at +/- 7 knts/hr heading into an incoming tide in the Oakland estuary (not stiff). It looked like we could drop from 3000 to 2550 and only slow down 3/4 of a knt/hr. Out on the Central Bay the tide slowed us down by 1 1/2 knts and more, without really heading into the tide, sort of crossing the Bay. When we got off the City front we turned around and put her at 2600 we were charging along at +/- 8, and my bottom is only so-so on the dirty side. Sure glad I don't have a twin screw fly bridge cruiser to buy fuel for.
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