62cruiserinc
Petty Officer 1st Class
- Joined
- Oct 30, 2009
- Messages
- 291
Hi everyone:
It's been a while since I posted.
I have a 1981 Sea Ray 260 Sundancer that I bought about 8 years ago. It has an MCM260 with alpha drive. The previous owner replaced the engine and the outdrive with an SE outdrive. The engine has an Edelbrock 4 barrel marine carburetor.
It was running well until last year my sonsaid the boat wouldn't restart a few miles offshore. He was towed in and I found water in the cylinders. Fortunately it ran fine after drying everything out. However, I suspected the exhaust shutters may have corroded away. There is a great local boat repair guy and I took the boat to him. He replaced the exhaust shutters and said the old ones were rotted away. He also put in new plug wires and plugs.
After the shutter replacement last year, it was late in the season and the boat only went out a few times by my son. He mentioned that it didn't seem to run as fast.
This year we did maintenance on the boat (gear oil, engine oil, etc) and we put in a new dash and did a lot of rewiring to clean up a messy wiring job. We put it in the water and now it tops out at 3K RPM and about 12mph.
It starts very easily and runs very smoothly, it just stops accelerating when it gets to 3K RPM.
The prop is the same one that has been on it all along and the hub is not spun.
The boat repair guy said to try pulling off one plug wire at a time at the distributor and see if the RPM drops. We did and the RPM dropped about the same for each of the 8 cylinders.
The boat has a Teleflex SL3 throttle and shift controller. One of the ideas was that maybe the throttle wasn't opening far enough at the carb. It does look like the carb throttle can more a little farther than the controller allows. However, it looks like the throttle range at the controller is less than the range needed to go from idle to full open throttle at the carb. When you push the button at the base of the SL3 handle to put it in neutral, the lever goes forward quite a distance before the internal mechanism starts to move the throttle lever. Adjusting the cable at the carb so it goes full throttle results in the throttle not going down all the way to idle and the "idle" is now at 1500 RPM. There doesn't appear to be an adjustment at the SL3 to lessen the "dead zone" in the lever from straight up to where it starts pulling the throttle cable.
I'm not even sure the throttle has anything to do with the 3K RPM "limit" I am having.
Any ideas would be greatly appreciated.
Thanks in advance.
Steve
It's been a while since I posted.
I have a 1981 Sea Ray 260 Sundancer that I bought about 8 years ago. It has an MCM260 with alpha drive. The previous owner replaced the engine and the outdrive with an SE outdrive. The engine has an Edelbrock 4 barrel marine carburetor.
It was running well until last year my sonsaid the boat wouldn't restart a few miles offshore. He was towed in and I found water in the cylinders. Fortunately it ran fine after drying everything out. However, I suspected the exhaust shutters may have corroded away. There is a great local boat repair guy and I took the boat to him. He replaced the exhaust shutters and said the old ones were rotted away. He also put in new plug wires and plugs.
After the shutter replacement last year, it was late in the season and the boat only went out a few times by my son. He mentioned that it didn't seem to run as fast.
This year we did maintenance on the boat (gear oil, engine oil, etc) and we put in a new dash and did a lot of rewiring to clean up a messy wiring job. We put it in the water and now it tops out at 3K RPM and about 12mph.
It starts very easily and runs very smoothly, it just stops accelerating when it gets to 3K RPM.
The prop is the same one that has been on it all along and the hub is not spun.
The boat repair guy said to try pulling off one plug wire at a time at the distributor and see if the RPM drops. We did and the RPM dropped about the same for each of the 8 cylinders.
The boat has a Teleflex SL3 throttle and shift controller. One of the ideas was that maybe the throttle wasn't opening far enough at the carb. It does look like the carb throttle can more a little farther than the controller allows. However, it looks like the throttle range at the controller is less than the range needed to go from idle to full open throttle at the carb. When you push the button at the base of the SL3 handle to put it in neutral, the lever goes forward quite a distance before the internal mechanism starts to move the throttle lever. Adjusting the cable at the carb so it goes full throttle results in the throttle not going down all the way to idle and the "idle" is now at 1500 RPM. There doesn't appear to be an adjustment at the SL3 to lessen the "dead zone" in the lever from straight up to where it starts pulling the throttle cable.
I'm not even sure the throttle has anything to do with the 3K RPM "limit" I am having.
Any ideas would be greatly appreciated.
Thanks in advance.
Steve