distributor cap and rotor

[Figacres]

Hi guys i have an older 4.3 mercruiser and doing a basic tune up and wondering if an auto cap/rotor would work? I ordered this one and it doesn’t fit my distributor. https://www.amazon.com/Ignition-Dis...936&s=gateway&sprefix=mercruiser+cap+&sr=8-11

my current cap uses a different style of plug then the one above.

 

[achris]

The cap and rotor are Merc specific, not automotive. Order your MARINE cap and rotor from a Merc dealer or MARINE aftermarket supplier. DO NOT use automotive parts on boat engines. They need to be MARINE certified, yes there is a difference. (they help prevent the boat going :boom

Chris.......

 

[muc]

The cap and rotor you linked to should have fit. Might want to post a picture of your distributor so we can see why it doesn’t.

 

[achris]

The cap and rotor you linked to should have fit. Might want to post a picture of your distributor so we can see why it doesn’t.

Interesting. I didn't look at the link, just saw 'automotive' and posted.

Yes, that is the right cap and rotor, so maybe the one on there now is automotive... :facepalm:

Chris.......

 

[Scott Danforth]

Hi guys i have an older 4.3 mercruiser and doing a basic tune up and wondering if an auto cap/rotor would work? I ordered this one and it doesn’t fit my distributor. https://www.amazon.com/Ignition-Dis...936&s=gateway&sprefix=mercruiser+cap+&sr=8-11

my current cap uses a different style of plug then the one above.

define older 4.3? post year as a minimum, post serial number

 

[Bt Doctur]

guessing is has points? where the plug wire goes in instead of the plug wire going on

 

[Bt Doctur]

or this type of electronic ign

 

[achris]

guessing is has points? where the plug wire goes in instead of the plug wire going on

Merc 4.3 only even came with TB-IV. The only 'pointed' V6 was the 229 (3.8L)...

Chris.....

 

[Bt Doctur]

could be prestolite dist with the electronic conversion

 

[achris]

could be prestolite dist with the electronic conversion.

Was never put on the Mercruiser 4.3.... 4.3s were only ever supplied with the Merc Thunderbolt distributor, until the late 90's when EFI and MPI came along.

Chris...

 

[Bt Doctur]

Better check manual 7 then

 

[achris]

Better check manual 7 then

I have.... here's the result. As I said, 4.3 NEVER came with a points distributor....

 

[Fun Times]

One thought is that sometimes the rotor may not get slid all the way down enough to it's proper position in-turn not allowing the cap to properly rest on the distributor housing.

 

[Scott Danforth]

since we do not know vintage or the history, it could also have a different ignition system in it from a prior owner. I say we wait until the OP returns.

 

[Figacres]

[No message]

 

[Figacres]

This is what I currently have. I forgot to check the engine numbers.

 

[muc]

From the picture it looks like a Delco cap that was used on the inline 6 cylinders?

 

[Scott Danforth]

This is what I currently have. I forgot to check the engine numbers.

get the numbers posted, also take a picture of the whole motor

I agree with muc, it looks like a points dizzy

 

[Bt Doctur]

A Prestoite that came with points. remove the dist cap and post a pic. Cold have the electronic conversion
Chris, the purple circled is a points dist spec

 

[Bt Doctur]