pine island fred
Lieutenant Junior Grade
- Joined
- Dec 20, 2002
- Messages
- 1,144
Just finished helping a friend replace his engine. Old set up was a 290 DP with a 305 with a 4 barrel. Old engine seized due to saltwater incursion about 1 maby 2 yrs. ago. ( UGLY). So he buys a new block, 350, minus the manifolds, distributer, carb and other accessories, with although speed is not supposed to be important to him, a roller cam.
So we drop it in the water and idle around for 2 hrs. never exceeding 1500 rpm. as per break in instructions. FRI. evening was the day for the big event so 6 of us pile on board with champaign for the big event. I had completely drained the tank, installed a new fuel filter, and added 40 gallons of fresh gas. No water on board, just 6 people on a 23 ft. chaparral. He opens up the throttle and the engine peaks out at 3800 RPM, on plane , motor sounds fine. Old engine turned around 4600 after we got it propped correctly, expensive operation, before it failed. We expected it to do the same or better with the new mill but 3800 was the best it would do.
I had set the timing at 8 degs. BTDC and did not hear any detonation. The old carb was off a 305, could the difference of 45 cu. be that important ? I figured a smaller carb would not increase the manifold pressure and since speed was not important to him, although he only goes idle speed manitee zone or WOT, we could save him a few bucks on this money pit by utilizing the old carb. Was I wrong?? The manifolds are off the old 305. Intake is original 1991 and exhaust has about 4 hrs. on them. Distributer is also very low hrs due to the centrifigul advance self distructing in the old one.
Can anyone give me some guidance? Boy I am glad it is not my boat, he has about 15K tied up in this thing, so much for a bargain purchase price. Also the outdrive 290DP is new along with the props. Also the old gas I removed worked just fine in all the neighbors vehicles as well as a friend suzuki. thanks FRED
So we drop it in the water and idle around for 2 hrs. never exceeding 1500 rpm. as per break in instructions. FRI. evening was the day for the big event so 6 of us pile on board with champaign for the big event. I had completely drained the tank, installed a new fuel filter, and added 40 gallons of fresh gas. No water on board, just 6 people on a 23 ft. chaparral. He opens up the throttle and the engine peaks out at 3800 RPM, on plane , motor sounds fine. Old engine turned around 4600 after we got it propped correctly, expensive operation, before it failed. We expected it to do the same or better with the new mill but 3800 was the best it would do.
I had set the timing at 8 degs. BTDC and did not hear any detonation. The old carb was off a 305, could the difference of 45 cu. be that important ? I figured a smaller carb would not increase the manifold pressure and since speed was not important to him, although he only goes idle speed manitee zone or WOT, we could save him a few bucks on this money pit by utilizing the old carb. Was I wrong?? The manifolds are off the old 305. Intake is original 1991 and exhaust has about 4 hrs. on them. Distributer is also very low hrs due to the centrifigul advance self distructing in the old one.
Can anyone give me some guidance? Boy I am glad it is not my boat, he has about 15K tied up in this thing, so much for a bargain purchase price. Also the outdrive 290DP is new along with the props. Also the old gas I removed worked just fine in all the neighbors vehicles as well as a friend suzuki. thanks FRED
