Please help me identify my boat engines

I am buying a 28' houseboat with this picture of the engines, any info would be much appreciated...in regards to this photo..any guess would be much appreciated. ie...what kind, horsepower, gpm etc etc is the thing on the left a generator. thank you snickers are o.k. too

Can't blow them up, the photo so can't see.

Try again.

volvo b30 or aq 170 engine

I have determined they are twin volvo car engines from the 60's about 175 horsepower ..now i am thinking about the fuel burn in a 28' x 8' fiberglass about 8,000 lbs i know the car did not do very well with mpg. >> any guess??
thanks

Thirty plus years ago Volvo 6 cylinder gas engines were factory marinized and hooked up to their outdrive. Assuming these are the marinized version they should do fine.

The fuel pump looks over the road though, exactly like one that I had on a car that IGNITED. Do a bit of research and talk to some Volvo marine old timers.

Probably 3liter or so, probably around 100hp. Burn rate with two running probably around 1-1.5gal/hr ea at hull speed of about 5-6kts. If boat can run at planing speed, probably about 5gal/hr ea at 3/4 power. Wild guesses, these, but probably close.

Gasoline engines have poor efficiency at low power settings (but of course burn less fuel at low setting, just convert less of it to hp), so if running low speed you might do better on one engine. I think the volvo outdrives can freewheel without restriction as they have mechanical clutches.

Fuel fire safety and carbon monoxide safety are critical with these. Us with diesel power can sort of forget how important this is on a gasoline boat with living spaces.

zinco said:

I am buying a 28' houseboat with this picture of the engines, any info would be much appreciated...in regards to this photo..any guess would be much appreciated. ie...what kind, horsepower, gpm etc etc is the thing on the left a generator. thank you snickers are o.k. too

Click to expand...

A normally aspirated automotive/marine gasoline engine typically produces around 10HP/Gal/hr. at WOT. That is a generalization of course, but it is a good starting point . Most I/O installations have actual fuel consumption a few percent below that number. In your case, at WOT, I would expect each AQ170/B30 to consume up to 17Gal/hr., but probably more like 15-16Gal/hr. as installed in a boat with the correct propellers and pitch. Since you would operate the engines well below their full rated power, it will be very dependent on the speed at which you choose to operate your boat. With twins operating at 50% power you would conceivably see around 16Gal/hr. At 33% power, 10-11Gal/hr. and so on. Without Volvo's published power curves, knowing the corresponding engine RPM's for those power settings will be anybody's guess.

Most, if not all AQ170s came from Volvo with Bosch marine alternators. As I recall, some were pretty small, around 35A or so. Aftermarket replacements are readily available though.

Hope this helps.

Larry
M/V Boomarang

My long time experience with a Mercruiser 165 (Chevy straight 6) was a burn rate of about 5 gph at 3000 RPM. I'd estimate these engines at houseboat speed of 2000 RPM to burn no more than 3 gph apiece.