Throttle cable adjustment dimension 5.7 EFI

[khe]

What is the dimension between the barrel and the throttle cable end on a Mercruiser 5.7 EFI? Is the dimension from the barrel hole to the hole in the cable end or some other feature on the end of the cable?

 

[Bondo]

What is the dimension between the barrel and the throttle cable end on a Mercruiser 5.7 EFI? Is the dimension from the barrel hole to the hole in the cable end or some other feature on the end of the cable?

Ayuh,..... In neutral / at idle, the cable is adjusted to put slight pressure against the idle stop,....

 

[khe]

Thanks. I should probably post another thread that is more descriptive of the symptom. I am in the process of replacing my engine due "fire notching of the block and head which lead to a loss of compression on cylinders 3 & 5.

I followed the instructions with the remanufactured engine on how to break in the camshaft and changed the engine oil after that procedure.

I set the base timing to 8° and the issue I am having is when I throttle back down to neutral, the engine will idle around 600 RPM for a few seconds and then die. It will restart with a slight amount of throttle. All sensors are plugged in and I thought it might be the throttle cable adjustment but now I think it may be something else but I need to know what to look at next.

 

[alldodge]

Would need to know more about the motor, happen to know the original serial number?

Being a EFI it should be a vortec motor with roller cam so the cam shaft would not need to be broke in like on a flat tappet cam.

 

[Bondo]

Thanks. I should probably post another thread that is more descriptive of the symptom. I am in the process of replacing my engine due "fire notching of the block and head which lead to a loss of compression on cylinders 3 & 5.

I followed the instructions with the remanufactured engine on how to break in the camshaft and changed the engine oil after that procedure.

I set the base timing to 8° and the issue I am having is when I throttle back down to neutral, the engine will idle around 600 RPM for a few seconds and then die. It will restart with a slight amount of throttle. All sensors are plugged in and I thought it might be the throttle cable adjustment but now I think it may be something else but I need to know what to look at next.

Ayuh,.... You just described it, so this thread will work,.....
It's in the posting rules, 'n guidelines, one thread per problem,.....

 

[khe]

Would need to know more about the motor, happen to know the original serial number?

Being a EFI it should be a vortec motor with roller cam so the cam shaft would not need to be broke in like on a flat tappet cam.

The boat is a 1997 model year and the original engine's serial no. was 0K007751 which matches the label on the electrical box cover and the tag on the original engine. It is not a Vortec motor.

 

[alldodge]

Agree, was right during change over. Serial number shows both roller and flat

Most likely your issue is with the IAC but might be a slight vacuum leak

There isn't a dimension for throttle cable, it's done by feel. As Bondo mentioned, adjust cable so it just fits in place, then remove and turn barrel out one more turn so it applies a slight bit of pressure holding TB closed

 

[khe]

Agree, was right during change over. Serial number shows both roller and flat

Most likely your issue is with the IAC but might be a slight vacuum leak

There isn't a dimension for throttle cable, it's done by feel. As Bondo mentioned, adjust cable so it just fits in place, then remove and turn barrel out one more turn so it applies a slight bit of pressure holding TB closed

How would I test the idle air control motor? It is strange that I did not have this issue before the engine swap.

 

[alldodge]

Remove IAC, reconnect connector, turn key ON and see if the tip moves.

Inspect tip and port for crud. If it needs cleaning, don't use anything caustic like carb cleaner, soap and water is best

Remove IAC muffler (foam filter) and see if it needs cleaning

After that, that's about it, they either work or they don't

 

[khe]

Remove IAC, reconnect connector, turn key ON and see if the tip moves.

Inspect tip and port for crud. If it needs cleaning, don't use anything caustic like carb cleaner, soap and water is best

Remove IAC muffler (foam filter) and see if it needs cleaning

After that, that's about it, they either work or they don't

Thank you very much! I'll try that this evening. It's strange that it was OK before the swap. Everything has been fighting me on this project.

 

[khe]

I tested the IAC tonight and it extended with the ignition on and retracted with the ignition off. I started the engine and it idled perfectly but once the engine came up to operating temperature, it stalled and would not restart unless I gave it some throttle.

I had an idea to spray the IAC motor with electronic "freeze spray" and the engine idled perfectly for about five minutes and then it died. Prior to that it would only idle for about two to three seconds before it died.

I'm thinking the IAC has an issue when it heats up. It's strange that it wasn't sn issue before I did the engine swap.

 

[alldodge]

Without a scanner were guessing, but does look like a IAC issue.

 

[khe]

Without a scanner were guessing, but does look like a IAC issue.

I have an old OBD-1 scan tool for automotive but I'm fairly sure the diagnostic connector is different between the marine and the GM automotive application.

I unplugged the IAC motor and tested the four pins on the wire harness with a test light and it illuminated and blinked when the ignition key was cycled so I think it is receiving the signal from the ECM.

Also, when the engine is warm, if I crack the throttle slightly while in neutral, I can get it to idle close to 600 RPM but as soon as I put the throttle lever in neutral, the engine will die after 2-3 seconds.

 

[alldodge]

That is classic signs of IAC failure

 

[khe]

I had the base timing close yesterday but after a conversation with the remanufactured engine supplier, I got the base timing exactly at 8° before TDC tonight and the stalling issue went away.

I need to install the stern seat and then it's time to take it out on Lake Michigan for a trial run.