snsrider717
Recruit
- Joined
- Mar 20, 2013
- Messages
- 4
Thank you in advance for any help you can provide with this incredibly frustrating issue.
Boat: 1986 Sea Ray 21' Cuddy Cruiser
Engine: Original 5.7L 260 HP Mercruiser with Alpha 1 Gen 1
Problem: Engine runs perfectly for approximately 20 min at all RPM ranges, and then inexplicably starts to have timing issues. I should say I am 90% or more certain it is timing. After about 20 min the motor begins to struggle to maintain any RPM above 3000. It will however cruise steadily at about 2800.
After the motor completely cools off, say after a couple hours, it runs perfectly again.
I just replaced the Thunderbolt IV module thinking that it was going bad, but no change. It has new plugs from last year, and I replaced the sensor in the back of the distributor after I lost all spark about 4 months ago.
Other notes: Brand new Carb, new gas, new fuel filter, good compression and spark whenever I test it.
I'm desperate to get this resolved as I have a buyer who wants to take it for a test drive.
Thanks again for any advice you might have.
Boat: 1986 Sea Ray 21' Cuddy Cruiser
Engine: Original 5.7L 260 HP Mercruiser with Alpha 1 Gen 1
Problem: Engine runs perfectly for approximately 20 min at all RPM ranges, and then inexplicably starts to have timing issues. I should say I am 90% or more certain it is timing. After about 20 min the motor begins to struggle to maintain any RPM above 3000. It will however cruise steadily at about 2800.
After the motor completely cools off, say after a couple hours, it runs perfectly again.
I just replaced the Thunderbolt IV module thinking that it was going bad, but no change. It has new plugs from last year, and I replaced the sensor in the back of the distributor after I lost all spark about 4 months ago.
Other notes: Brand new Carb, new gas, new fuel filter, good compression and spark whenever I test it.
I'm desperate to get this resolved as I have a buyer who wants to take it for a test drive.
Thanks again for any advice you might have.