Setting the timing

[brian3127]

I have a 1972-1977 mercruiser 3.0. Serial number 4920382
I have seen on YouTube that you have to put the engine in base mode to set the timing.
My mercruiser service manual tells me to run the engine at idle and set it to 6 degrees btdc.

What years did they change it

 

[Bondo]

Ayuh,..... Loonnngggg after when yers was built,.......

 

[brian3127]

The engine I have does not have points.
Do I still set it to 6* btdc

 

[achris]

I have a 1972-1977 mercruiser 3.0. Serial number 4920382
I have seen on YouTube that you have to put the engine in base mode to set the timing.
My mercruiser service manual tells me to run the engine at idle and set it to 6 degrees btdc.

What years did they change it

That's a 1978 engine, and it'll have points.

Set the points at 22 thou, then the timing to 6 BTDC. (Don't believe everything you see on youtube, there is no 'base timing mode' for this engine.)

Chris......

 

[brian3127]

No points there is an ignition module

 

[achris]

Interesting. Maybe someone has changed the distributor over for a later model. ???
This your timing procedure and setting. (1 degree BTDC)

 

[brian3127]

Interesting. Maybe someone has changed the distributor over for a later model. ???
This your timing procedure and setting. (1 degree BTDC)

View attachment 353983

That’s why I’m confused
The engine is in the process of getting rebuilt and I want to make sure it’s set right.
About $1000 in work at the machine shop plus parts. Me and my son are putting together. So I’m wondering

 

[Scott06]

That’s why I’m confused
The engine is in the process of getting rebuilt and I want to make sure it’s set right.
About $1000 in work at the machine shop plus parts. Me and my son are putting together. So I’m wondering

Some one added a delco est kit to it , common upgrade that was also used by merc and volvo penta over the years. Chris has steered you right on how to set it make sure you can measure the total advance with an advance timing light or put a timing tape on the balancer

 

[brian3127]

Ok thanks guys

 

[kenny nunez]

Make sure that the machine shop replaces the bushing in the block for the lower distributor shaft above the oil pump.

 

[Scott Danforth]

Make sure that the machine shop replaces the bushing in the block for the lower distributor shaft above the oil pump.

yes, that under $10 part wears. its also available at any NAPA