87 Formula thunderbird
Recruit
- Joined
- May 26, 2009
- Messages
- 1
Hi there - hope someone can help!
Have an 87 Formula Thunderbird with twin 350 Mercruisers Alpha 1....Went out for the first run of the season - everything ran great. Second time out we noticed a substantial vibration on take off...throughout acceleration up to about 3000 rpm... also noticed that the engine rpms were not in sync. Port side was revving slightly higher than starboard. The vibration eased off some above 3000 rpm. Engines sound great - smooth at idle. No unusual noises just the vibration under acceleration. Thought we possibly spun the port side prop. Removed and inspected (fixed hub style quicksilver) and can't see any visible damage within the hub...although we did see some ground rubber pieces. Inspected and marked the shaft and the prop - reinstalled it and took it out and gagged it to see if there was any slipping. The marks are lined up. Have purchased a new prop just in case...haven't put it on yet...trying to do that tomorrow and hopefully it will work and I will send the existing out for repair to keep as a spare. However, a couple local guys have said that if the marks line up (which they did) then the problem is further up in the drive. Speculation had gone from the prop issue through the drive to a mount at back of engine.....Please help. Don't want to go on bank breaking wild goose chases. Is there anything else we can check? Thank you!
Have an 87 Formula Thunderbird with twin 350 Mercruisers Alpha 1....Went out for the first run of the season - everything ran great. Second time out we noticed a substantial vibration on take off...throughout acceleration up to about 3000 rpm... also noticed that the engine rpms were not in sync. Port side was revving slightly higher than starboard. The vibration eased off some above 3000 rpm. Engines sound great - smooth at idle. No unusual noises just the vibration under acceleration. Thought we possibly spun the port side prop. Removed and inspected (fixed hub style quicksilver) and can't see any visible damage within the hub...although we did see some ground rubber pieces. Inspected and marked the shaft and the prop - reinstalled it and took it out and gagged it to see if there was any slipping. The marks are lined up. Have purchased a new prop just in case...haven't put it on yet...trying to do that tomorrow and hopefully it will work and I will send the existing out for repair to keep as a spare. However, a couple local guys have said that if the marks line up (which they did) then the problem is further up in the drive. Speculation had gone from the prop issue through the drive to a mount at back of engine.....Please help. Don't want to go on bank breaking wild goose chases. Is there anything else we can check? Thank you!