Logo
FULL SITE MENU

Twin 270HP crusaders help

S

shamlesteberg

New member
I have a 33' 1977 Carver M

I have a 33' 1977 Carver Mariner with twin 270 crusaders. Top speed was about 27 mph by GPS. Boat sat for about 2 months and now only tops out at about 13 mph. Engines run well with no load but bog down when opened up. Thinking transmissions but both at the same time? Maybe fuel quality? No clue here.
 
"Check fuel filters along with

"Check fuel filters along with fuel quality. Are you mandated to use an ethanol blend fuel? This absorbs moister.

I don't know were you are, but after sitting two months it could also be a lot of growth on the bottom."
 
"Leinieman: minimal growth on

"Leinieman: minimal growth on bottom, checked July 4th. Started doing this a few days before. I'm in Washington. Not sure if the gas was E10 or not, haven't gotten to go back to pump to check. How else can I check fuel quality?

Victor: Me too. It does not backfire under load. Does it even when I bypass fuel filters.

Thinking bad gas, something clogged both carbs, or some bad gas fouled plugs (but all 16?)"
 
"I'm just trying to find s

"I'm just trying to find something common to both engines and I should have my culprit. Each has it's own electrical, electric fuel pump, fuel filters, fuel pump pickup in gas tanks etc..."
 
"OK, so I used some carb clean

"OK, so I used some carb cleaner with no real results. I then used a 5 gallon jerry can connected to the inlet of each electric fuel pump and got maybe one mph more. I pulled a plug and it was pretty black so my next step will be changing the plugs out."
 
"So I checked the carbs, ran s

"So I checked the carbs, ran some seafoam all seems well on the fuel/carb side. Went out today and got only 15 kts. Rev'd engines seperately and STBD is fine in forward and reverse. Port maxes out about 3000 rpm. Getting fuel fine so I'm thinking the port transmission is going. No sign of slippage just can't rev up under load. Any ideas?"
 
"Shane,

Did you figure this

"Shane,

Did you figure this out? I took my twin 220's out last night and I have the same problem. Starboard engine won't get to 3000 rpm under load. Rev's up fine when not engaged."
 
Back
Top