HEI distributor timing advance: confused how this works?

[NJCoastFlyFish]

I have a 5.7L Marine Power engine 1987-1993 (GM Block) Carbuerated. I noticed the engine running a little odd, I hooked the timing light up to it and the timing was fluctuating on start up. It was actually at a few degrees ATDC then would finally settle in on 8degrees BTDC. This engine also doesn't seem to be getting enough advance at higher RPM. I am trying to figure out if I can replace parts on the distributor to fix this without buying a whole new distributor? I also want to set the advance a little more degrees.

This distributor has the remote coil with the 8 pin ignition control module mounted on the distributor. I noticed that one of the ports on the ignition control module, the 4 pin port, has nothing connected to it. After doing some reading cars this port is connected to an EFI system and it helps control timing advance. Is my engine missing parts or is this port redundant for marine use and carbuerated use?

This distributor is still advancing timing, but it is acting a bit whacky and i'm not sure why or how it is advancing timing without the 4 pin port being connected. If anything has dealt with this type of ignition system before I would really appreciated any help as it has my pretty confused.

Tom

 

[Bondo]

Re: HEI distributor timing advance: confused how this works?

I have a 5.7L Marine Power engine 1987-1993 (GM Block) Carbuerated. I noticed the engine running a little odd, I hooked the timing light up to it and the timing was fluctuating on start up. It was actually at a few degrees ATDC then would finally settle in on 8degrees BTDC. This engine also doesn't seem to be getting enough advance at higher RPM. I am trying to figure out if I can replace parts on the distributor to fix this without buying a whole new distributor? I also want to set the advance a little more degrees.

This distributor has the remote coil with the 8 pin ignition control module mounted on the distributor. I noticed that one of the ports on the ignition control module, the 4 pin port, has nothing connected to it. After doing some reading cars this port is connected to an EFI system and it helps control timing advance. Is my engine missing parts or is this port redundant for marine use and carbuerated use?

This distributor is still advancing timing, but it is acting a bit whacky and i'm not sure why or how it is advancing timing without the 4 pin port being connected. If anything has dealt with this type of ignition system before I would really appreciated any help as it has my pretty confused.

Tom

Ayuh,.... Post a picture of the distributor,.... Delco HEI is an Automotive Only distributor,...

Is this distributor original to this motor,..??

 

[NJCoastFlyFish]

Re: HEI distributor timing advance: confused how this works?

Bondo,

This distributor came with the boat when I bought it used. I have seen these distributors for sale under marine use. I posted a picture of a distributor I found online that looks exactly the same as mine only mine has a black cap. Under the cap is the rotor and a brass ring that sort of surrounds whatever it is that advances the timing, or so I assume.

Tom

 

[Bondo]

Re: HEI distributor timing advance: confused how this works?

Bondo,

This distributor came with the boat when I bought it used. I have seen these distributors for sale under marine use. I posted a picture of a distributor I found online that looks exactly the same as mine only mine has a black cap. Under the cap is the rotor and a brass ring that sort of surrounds whatever it is that advances the timing, or so I assume.

Tom

Ok, That's not a HEI, but I think the EST,.... Great distributor I hear,...

The advance is all electronic, no weights or anything movin',...
I believe that plug is where ya need a jumper wire to set the timin',...
Somebody'll be along with a better idea of it than myself,...

Up in Don'S Adults Only section, you'll find a ton of Info,...
Have a look around,....

 

[schematic]

Re: HEI distributor timing advance: confused how this works?

I have a 5.7L Marine Power engine 1987-1993 (GM Block) Carbuerated. I noticed the engine running a little odd, I hooked the timing light up to it and the timing was fluctuating on start up. It was actually at a few degrees ATDC then would finally settle in on 8degrees BTDC. This engine also doesn't seem to be getting enough advance at higher RPM. I am trying to figure out if I can replace parts on the distributor to fix this without buying a whole new distributor? I also want to set the advance a little more degrees.

This distributor has the remote coil with the 8 pin ignition control module mounted on the distributor. I noticed that one of the ports on the ignition control module, the 4 pin port, has nothing connected to it. After doing some reading cars this port is connected to an EFI system and it helps control timing advance. Is my engine missing parts or is this port redundant for marine use and carbuerated use?

This distributor is still advancing timing, but it is acting a bit whacky and i'm not sure why or how it is advancing timing without the 4 pin port being connected. If anything has dealt with this type of ignition system before I would really appreciated any help as it has my pretty confused.

Tom

You will not be able to adjust advance.....only base timing. Advance is programmed into the ECM. As Bondo says, there is a procedure to follow to when adjusting base timing. I believe you have to disconnect the 5v bypass. You need the manual.