ignition amplifier 3.8L 1984 mercruiser

orchie18

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We have replaced the motor and hooking everything up, changed the distributor to electronic, we have a existing ignition amplifier module ( i think thats what it is) thats wired into the harness, what exactly does it do and hows that going to work with the electronic distributor. its a black module mounted on a plate that mounts on back of engine with 2 bolts.
 
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Don S

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Re: ignition amplifier 3.8L 1984 mercruiser

Best to post the Mercruiser serial number for your engine in order to get the proper information.
 

Howard Sterndrive

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Re: ignition amplifier 3.8L 1984 mercruiser

there is no marine electronic ignition for the 3.8

you have to use the prestolite IBM7014 distributor with points. there are no other options
 

orchie18

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Re: ignition amplifier 3.8L 1984 mercruiser

The 3.8 was in a 84 malibou 80000k it had a electroinc distributor running it.
What is the reason we have to revert back to pionts and coil ignition?

Definately need some input here on this.

Tks for reply
 

Bt Doctur

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Re: ignition amplifier 3.8L 1984 mercruiser

Exactly what is a 3.8 mercruiser? Havent run across one.
 

Howard Sterndrive

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Re: ignition amplifier 3.8L 1984 mercruiser

The 3.8 was in a 84 malibou 80000k it had a electroinc distributor running it.
What is the reason we have to revert back to pionts and coil ignition?

Definately need some input here on this.

Tks for reply

1. the car HEI is not rated per SAE J1171 .... External Ignition Protection of Marine Electrical Devices.
It'll run, but there's a slight risk of explosion.... and scrutiny from coast guard, insurance etc..

2. that Malibu HEI is advanced for the characteristics of the 110HP smog motor, not the 170/185HP boat motor. I'm not sure how it would suit the power curve with the boat cam... might be fine. or might rob some power

with point 2, you do not want that motor in a boat without changing the cam to the one from the original motor...or for new, Edelbrock EDL2112 is the same as the marine grind.
the smog control was all in the cam and the price was about 50HP


I don't think there's any ignition amplifier on your setup. Sounds like you might be looking at the shift interrupt system.

If you have the original distributor you would probably be better off using it.

Can go to the adults only sticky and download the manual.
 

Don S

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Re: ignition amplifier 3.8L 1984 mercruiser

Definately need some input here on this.

Tks for reply


So do we, that is exactly why I asked for a Mercruiser serial number. things are not always as you think they are.
 

orchie18

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Re: ignition amplifier 3.8L 1984 mercruiser

The cam has been changed, So the original distributor and point system is safer i guess, this info i did know, reading above regarding electronic dist. would be the other option sounds like. What about other spark emitting parts, plug wire etc?
Tks again
Frank
 

orchie18

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Re: ignition amplifier 3.8L 1984 mercruiser

I will get the number, Being new to this marine business can be very enlightening.
tks
 

Don S

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Re: ignition amplifier 3.8L 1984 mercruiser

The cam has been changed, So the original distributor and point system is safer i guess,

Why would you think that? Just because it's newer? Automotive is never ignition protected. No need for it. That is why marine has a lot of different electrical parts than automotive. Same with the fuel systems. Then, just think about all the reversion you can get by using the wrong kind of cam in a marine engine.
Then you get to suck water back into your cylinders when running.
 

Howard Sterndrive

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Re: ignition amplifier 3.8L 1984 mercruiser

Exactly what is a 3.8 mercruiser? Havent run across one.
chevy V6 229 cid 185HP with a quadrajet
often called the MR185 or 185/V6

not sure how or why Merc marketed it along side the 4 cylinder 224cid of similar power at the time.

same engine as OMC 3.8 and VP AQ175A of same time frame
 
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