re-power CC Roamer Offshore (38ft)

Not displacement hull

The Roamer Offshore hull is not a displacement hull. It is very flat aft but with a sharp entry. It should be fine for outboards (other than size and weight).

Flat Aft

Bow turns into keel

http://www.marineenginedigest.com/specialreports/multiplicity.htm

Excerpt:
"Today Proline, Dakota, Midnight Express, Contender, Deep Impact, and Angler all build 30 to 40 foot boats specifically engineered for triple installations. Some of them also offer quadruple outboard powered boats. Obviously the chief attraction of multiple engine installations is extreme high performance. Triple and quadruple powered 30 - to 40- footers blister the water at speeds of 60 to 70 mph. Cruising speeds typically register in the 40 mph range. Clearly these boats are not intended for the feint of heart. One builder joyously boasts that when the Gulfstream lays flat like glass, his boats can make a Miami to Bimini run in 41 minutes flat. When seas are rough, it takes only a little while longer."

Obviously you're not looking for speeds like that, but you aren't looking for triples, either.

http://www.duckworksmagazine.com/04/s/columns/max/23/index.cfm

Excerpt:
Along with the technical paperwork comes an occasional gem, and I have posted one here; a 1961 promotional write-up concerning a 40 foot wooden Elco cruiser that was repowered with twin 75 hp Johnson outboards. Although repowering an older inboard boat with outboards is common now, it was something unusual back then.

The author points out that the outboards not only delivered higher speeds than the 135 hp gasoline inboards that they replaced, but burned less fuel as well.

Email sent. Let me know if you cannot open them. I can reprint the majority of the article as text here. They aren't that big.

Yamaha makes 350HP o/b's, but that would be well over the traditional power that you currently have. I would think 300's would be more in line with your need, but who can complain about more power? If you have nothing but cash to burn, Seven makes a 556HP O/B, but I think it's ranging about $75,000 apiece right now. It's a Cadillac Northstar engine that's used in the CTS-V autos.

Failures

Repetitive blown engines ?? Something's not right. Are you wide open all the time?

I agree, something is wrong there. Anyways, Outboards are easy on maintanence, fuel efficient and quiet if you go with 4 strokes, and you can get long warranties on them.

Overpropped and bad gas?

Yes, but there is a huge difference between a good rebuilding shop that specializes in automotive and one that specializes in marine. What compression ratio did they rebuild the motors with? Also ignition timing being too high could be another big problem if the gas you're using is high octane and the engines are not overpropped.

What RPM did you get at WOT? Or was that WOT?

It sounds like simple bad luck. With the latest engine mods and factory rebuilt V-drives you are not exactly stuck with antique worn out machinery. So what if the engines and the drives were designed 50 years ago? Your propeller technology has been around for about 200 years and it still works. "Old technology" isn't necessarily bad, it's just been around long enough to be proven. Bad technology doesn't last long enough to get old. Cast iron actually improves with age and new parts are new parts.

I would send the V-drives back to Walter for overhaul and testing. Rebuild or replace the blown engine and spend the savings on gas and good food for the next few years.

Convert Article

I thought the article was excellent and I can totally appreciate your love/hate feeling on the Roamer Offshore. In nearly 5 years of ownership, I also do not feel that I have gotten full use of the boat because of mechanical reasons. too much down time, too much expense after 20+ years of easy living with diesel sailboats. There certainly is an attraction with outboards.