Need help identifying ignition system... PICS INCLUDED

[CaptainMak]

I went to check to see what kind of ignition system I have to double check the timing on my engine.
Upon digging deep on the Net, I "think" I have the MEFI 3 system. (pics below).

Now, this part is confusing. I thought the MEFI system is only on fuel injected engines, but mine is a 2 bbl carb.
Can someone explain this ?
I found a DIY test light and base time paper clip and LED light here in the forums, but am still confused how I can have the EFI ignition on a carb engine.

Engine serial # 0M019033
Model # 4M31027N1

 

[thumpar]

Does it have a throttle body or carb? Got a serial number handy?

 

[CaptainMak]

Does it have a throttle body or carb? Got a serial number handy?

I put the serial number right above the pics. Serial # 0M019033

I think it's the throttle body. 2 injectors with wires coming to them

 

[thumpar]

Sorry I somehow missed the text of your post. It is EFI so it doesn't have a carb. I think it is MEFI 3.

 

[achris]

It is a MEFI3, and what you are looking at thinking is a carb is the throttle body injection system.

 

[Fun Times]

Sometime the distributor system on these/some EFI engines can be confusing as your engine uses parts from the thunderbolt V designed distributor ignition system used on "some" not all EFI engine models which is also found on carbureted engines too. Other EFI or MPI ignition systems are called Delco EST from Mercruiser.

http://www.boatfix.com/merc/bullet/99/99_02.PDF

Here's your OEM parts catalog for you, http://www.iboats.com/5-0L-EFI-GM-305-V-8-1999-2001-0L331631-THRU-0M299999/dm/view_id.1683216

 

[CaptainMak]

Thanks for all the info. Will be checking it out this weekend. Found the diagnostics plug. Now to figure out how to get to the pulley to see timing marks.