Ryanmash
Recruit
- Joined
- Jun 11, 2018
- Messages
- 5
Hi all,
Long time lurker, first time poster. I must admit I find a great deal of information and answer within this forum however I have become absolutely stumped. Wanted to reach out to this community to see if I can generate an answer.
About the boat - 1995 26ft Thompson 5.7l Mercruiser EFI, Alpha one gen II. Long story short had a blown head gasket at the end of the season water leaked on top the piston rusted the cylinder walls bent connecting rod. Now that we cleared that up, went out bought a new Mercury long block pre-vortec roller cam, removed necessary components from the old engine to the new. Replaced old distributor rotor and cap, have it pointed to no.1 cylinder TDC. Dropped engine into the boat and it turns over great get just enough fuel to burn and then shuts down. I can pour gas into the throttle body to get the engine to run, I can also see the injectors "misting" fuel. I can continue to add gas to keep the engine running however when I stop the engine will die.
My initial thought was the fuel pump was not delivering enough fuel so took the line off the throttle body and started the engine with gas and pumped the fuel into a bottle. This tells me the fuel pump is working properly as it filled the bottle in a matter of seconds. Next step I thought the injectors were dirty, so I pulled them off bought the rebuild kit and put it back together, no dice same problem. Got to reading on here and saw a post about a TPS and IAC sensor. So again I started the motor with gas, and disconnected the TPS sensor and the engine would go up to 3000 rpms but it would continue to run. So I figured ok TPS sensor is shot, went to parts store bought a new sensor, installed it, and same results.
At this point I have a day used up trying to find a solution. Found a link on this forum on how to create own test kit to determine engine error codes. Followed the instructions and pulled code 21. TPS voltage high. I am not exactly sure what that means or how to solve.
This is really strange as the old engine worked great never had any issue and now swapped it over to a new long block and i cannot get this thing to run at all. Hoping someone here can give some insight.
Thanks in advance,
Ryan
Long time lurker, first time poster. I must admit I find a great deal of information and answer within this forum however I have become absolutely stumped. Wanted to reach out to this community to see if I can generate an answer.
About the boat - 1995 26ft Thompson 5.7l Mercruiser EFI, Alpha one gen II. Long story short had a blown head gasket at the end of the season water leaked on top the piston rusted the cylinder walls bent connecting rod. Now that we cleared that up, went out bought a new Mercury long block pre-vortec roller cam, removed necessary components from the old engine to the new. Replaced old distributor rotor and cap, have it pointed to no.1 cylinder TDC. Dropped engine into the boat and it turns over great get just enough fuel to burn and then shuts down. I can pour gas into the throttle body to get the engine to run, I can also see the injectors "misting" fuel. I can continue to add gas to keep the engine running however when I stop the engine will die.
My initial thought was the fuel pump was not delivering enough fuel so took the line off the throttle body and started the engine with gas and pumped the fuel into a bottle. This tells me the fuel pump is working properly as it filled the bottle in a matter of seconds. Next step I thought the injectors were dirty, so I pulled them off bought the rebuild kit and put it back together, no dice same problem. Got to reading on here and saw a post about a TPS and IAC sensor. So again I started the motor with gas, and disconnected the TPS sensor and the engine would go up to 3000 rpms but it would continue to run. So I figured ok TPS sensor is shot, went to parts store bought a new sensor, installed it, and same results.
At this point I have a day used up trying to find a solution. Found a link on this forum on how to create own test kit to determine engine error codes. Followed the instructions and pulled code 21. TPS voltage high. I am not exactly sure what that means or how to solve.
This is really strange as the old engine worked great never had any issue and now swapped it over to a new long block and i cannot get this thing to run at all. Hoping someone here can give some insight.
Thanks in advance,
Ryan
