Electronic ignition for Mercruiser 170 (1985)?

scook · #1 03-24-2014, 01:44 AM

My distributor shaft is pretty sloppy and a supplier out here (pacific northwest) says electronic ignition will really boost performance. Since I need to fix it anyway I thought this might be a good time to do it right.

Any comments on whether electronic ignition is worthwhile and if so recommendations on what to get? I'm figuring on gettting a high voltage coil, etc.

A motorhead friend is suggesting a local ignition shop that does all kinds of engines but the supplier seems to have a lot of experience with 170's - I'm looking for a little more input.

I really want to be ready this year - supposed to be a record Salmon run - want to be in good shape for that.

twhrider2 · #2 03-24-2014, 04:51 AM

Pertronix 2 w/Flamethrower 2 coil and 8mm plug wires. I also opened plug gaps to .045. Good starts and will idle smoothly at 500 to 550 rpm.

spareparts · #3 03-24-2014, 05:30 AM

pertronix is the way to go, but if your distributor shaft is sloppy, it may create new problems, see if you can get the slop out of the shaft before you add to the issue. Is it in the shaft to housing fit? Or is it in the upper shaft to lower? Remember you can use a distributor for a 3.0L/2.5L 120/130/140 as a parts distributor if you can't find a 3.7L. The electronic ignition will help with the slop because there's no side load from the points, but it could lead to erratic timing if the there is enough play.

cfelton · #4 03-24-2014, 07:03 AM

Yep! The Pertronix ignition and the Flamethrower coil are definately the way to go!! Changed my 170 over years ago when I rebuilt the motor and it was a really good upgrade. Starts alot faster and runs 100% better. Keep your old points and condenser just in case.

scook · #5 03-24-2014, 11:13 AM

Thanks - I love it when everybody agrees. I need to dig into my manual about the upper/lower shaft thing and poke around the distributor to get the problem narrowed down. I'll get back with more questions when I understand what I don't understand better.

cfelton · #6 03-24-2014, 02:26 PM

The pertronix ignition module is really easy to install, Also I was told never leave your switch on when not running it could damage the module. I think Mallory makes a simular unit but havent heard anything about.

twhrider2 · #7 03-24-2014, 04:18 PM

cfelton ...you are correct about leaving the switch on with the pertronix 1, but the pertronix 2 is supposedly (smarter) and will shut down to protect itself also on low and high voltage.

THEFERMANATOR · #8 03-24-2014, 06:56 PM

Quote:

Originally Posted by twhrider2

cfelton ...you are correct about leaving the switch on with the pertronix 1, but the pertronix 2 is supposedly (smarter) and will shut down to protect itself also on low and high voltage.

Don't tell that to the model t guys. A common conversion on the model T is to add on a VW distributor, and many have added in the PERTRONIX 2 and had them melt down. One guy had an actual fire from it and did quite a bit of damage.

twhrider2 · #9 03-24-2014, 07:47 PM

Model T and VW cross had to be bad voodoo. Fire on V20 is no good.

DiverDux · #10 03-24-2014, 10:55 PM

We, my brother and I own an 87 V20 and we just had the ignition upgraded to an electronic unit. Do not know what brand, but we were assured a faster starting engine and slower trolling speed as we would be able to idle the engine down much lower than before. Haven't had it on the water yet, but we are expecting good things. Make the change, I'm sure you will be pleased. Have a safe boating season!