Ian Davies
New Member
I am changing the old md2 in my macwester 26 to the later more powerful md2b . Can anyone tell me if I need to change the prop ? I know that the 2b will rev faster which may give me the extra speed I seek.
Volvo penta md2 upgrade to md2b
- Thread starter Ian Davies
- Start date
Tranona
Well-Known Member
Enter your boat's data into a propeller calculator such as Propcalc on www.castlemarine.co.uk
AntarcticPilot
Well-Known Member
Doesn't work on OS more recent than Windows XP!
Tranona
Well-Known Member
Yes, I know, but I always assume that impoverished owners of old boats have old computers (like me)!
AntarcticPilot
Well-Known Member
I use mine to earn contributions towards marina fees, so I keep up to date
Ian Davies
New Member
Ta for that. I have windows 10. How do I find out details of the prop which is on my boat. Is the spec stamped on it somewhere?
Tranona
Well-Known Member
Yes, it is usually stamped on the hub, but maybe on a face which requires removing the prop.
Try www.vicprop.com which is a similar programme. I use Propcalc because I have had good experience with it and it is installed on my ancient Compaq. Alternatively give Castle Marine a call. They are competitive on new props or re-pitching existing.
Topcat47
Well-Known Member
Over 10 years ago, some parts for the MD range were unobtainable. I swapped my MD1b for a Yanmar. I hope you're confident about the replacement engine's condition.
PhillM
Well-Known Member
Same with my md7a - except I replaced with a beta 14.
scottie
Well-Known Member
Check engine footprint is the same
I have a suspicion that the 2 has narrower bearers
And if you are changing gearbox the securing bolt for the rear crankshaft carrier on the RB box has an oil jet hole
I have a suspicion that the 2 has narrower bearers
And if you are changing gearbox the securing bolt for the rear crankshaft carrier on the RB box has an oil jet hole
Ian Davies
New Member
Ta for that. , never thought to check the mount width as they look the same. You may have prevented a potential hold up. PPPPPP if you know what that means. I did see the oil hole when I stripped the spare I have.
Ian Davies
New Member
I bought two engines one for spares. I did the same with the old md2 and was very glad I did. I had great difficulty obtaining head gaskets and had some made. The 2b gaskets are still on sale. I shall prep a spare cylinder and head assembly to keep on the boat as head gasket blows seem to be common and it is a quick job to do if you don't have to prepare the gasket surfaces and slide on the complete assembly. Thanks for the heads up.
