bar none III
New member
I have twin 1986 454 model 350's with Rochester quadrajets. Both engines start on first crank and idle smoothly at about 800 & 1000 rpm. Not extremely confident in Tachs. I can run them in neutral at the slip for 45 to 60 minutes at various rpm's no problem. Whenever I attempt to go for a cruise, running at 1200 rpm for 15-20 minutes, trying to get out of the harbor, the engines die and will not restart immediately. There is no sputtering, the engines just cutout. After 15-20 minutes the engines will restart, but will only run 5-10 minutes under load and die again.
Sounds temperature related, maybe vapor lock. However, I have re-plumbed the entire fuel delivery system and installed the lines away from the block on the port engine and the issue still exists. There are no temperature issues with either engine.
Could the vapor lock occur within the mechanical fuel pump? This is obviously mounted on the engine block.
I have also installed electronic ignition and new coils as someone suggested heat could effect coils.
I thought I had read/heard that there are safety sensors installed for coolant temp, oil pressure and transmission temp, but they only provide an alarm. They will not shut down the engine. Is this the case?
Haven't been out yet this year. Anxious and aggravated.
Thank you in advance for any recommendations.
Sounds temperature related, maybe vapor lock. However, I have re-plumbed the entire fuel delivery system and installed the lines away from the block on the port engine and the issue still exists. There are no temperature issues with either engine.
Could the vapor lock occur within the mechanical fuel pump? This is obviously mounted on the engine block.
I have also installed electronic ignition and new coils as someone suggested heat could effect coils.
I thought I had read/heard that there are safety sensors installed for coolant temp, oil pressure and transmission temp, but they only provide an alarm. They will not shut down the engine. Is this the case?
Haven't been out yet this year. Anxious and aggravated.
Thank you in advance for any recommendations.