I am considering replacing my 25 year old Yanamr 2GM, with a new Beta BD722. My boat is a 30' Seafarer, (book disp. 8600lbs, crane said 10,000 bs loaded) A couple of questions: 1. Can the beta be ordered to fit the existing 2GM mount dimensions. I see the width is similar, but iz think the BD722 mounts are farther apart, front to back.
2. The engine beds are slightly angled, but the Yanmar is angled more, as the rear mounts are adjusted at least an inch lower than the front mounts, so that the shaft lines up. When considering a BD722, would you recommend a straight transmission, and angle the engine to match the old one, or use an angled transmission, and keep the engine relatively flat. I do not know the angle off hand, but will try to measure the current bed angle, and proper the shaft angle, against something flat, like the settee births, etc. I can't measure against a level, as the boat is not level!
You are making a very wise upgrade. When one repowers a boat, some of the necessary criteria are that the width of the mounts are the same (or very close to), the width of the mounts of the older engine, and that the same type of transmission (straight out, drop center or down angle) is used. If you have the mounts right and the same type of transmission, you will have a relatively easy install.
From past experience the BD722 fits on the same engine beds as the 2GM and 2GMF Yanmar. Expect to have to drill a few new holes because the flexible mounts are of a different size to the Yanmar ones but otherwise the new engine will fit on the same engine beds. You need to be careful with the transmission because if you have a standard drop center transmission, you need to go back with the same style. Yanmar were available with both and if you let me have the exact transmission model of your engine, I can make sure that the new engine will be compatible.
The Seafarer has a very easily driven hull and you can use the BZ602 (Beta16) and still have more power than the old 2GM had when it was new. The BD722 (Beta20) has much more power than the old 2GM and a little bit more than the 2GM20.
If you can send some photographs of your current installation, I may be able to see exactly what you have and then can advise you accordingly.
I look forward to hearing from you, Best wishes Stanley
Thanks for taking the time. I have 1 pic of the empty engine compartment, which does show the space, beds, etc, but may not be much help.
Th trannie is not in front of me now, but is the very common, KM2 - It's been a while since I looked at it. I will verify that next week. I will have limited computer access next week, but will be back after that!
I can email you the pic, but where do I send / attach it?
Email the photo to me at the office. My email address is stan@betamarinenc.com You can also post photos on this forum. The KM2P was the straight transmission and the 2GM20 with this transmission is comparable to the BD722 with the standard TMC40 transmission.
I will also be away most of next week. I am headed to the Maine Boatbuilders show and will be back in the office on March 19th. Lisa and Bob will however remain in the office.
pics of the engine beds. I was wrong, they are near level, but the rear bed mounts are stepped down (lower) than the front ones. In additions, the rear mounts lower nuts were set about an inch lower than the front ones.
I think that they used the stepped mounts to create the down angle that the boat builder needed to effect a good alignment. This will cause you no problem with your repower as the new engine will fit about the same as the old one.
Looking at the photos, I think that this will be a fairly easy repower. Regards, Stanley
Stanley - Thanks for the input. Yes, they did use the stepped down rear beds, to get the down angle. The beds are about 1/4" metal plates, glassed into place, and have threaded holes, to bolt the existing mounts to. I don't think it would be too much work to line -up a new engine, with the mounts just sitting on the beds. I could then mark the new bolt hole locations, drill and tap the matel plates, and bolt the engine down.
