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6ballsisall
04-01-2005, 10:44 PM
Is there a difference between marine plug wires and auto wires? Went to my local auto parts store the other day and picked up plug wires for an 86 351W and they are a no go. Seems the distributor connection types are different. Did I just get the wrong plugs or is there a difference?

JEREMY79
04-01-2005, 10:53 PM
I would like to know the answer to this also. I had the same problem last year. Thought I would change them before a trip to the lake. Ended up using my old wires and they are still on there.

TonyB
02-17-2006, 03:37 PM
You need to know what type connector you have.

Look at the pictorial reference on this pdf file. It's at the bottom

http://www.magnecor.co.uk/pdfs/magnecorkeytoapps01-04.pdf

However, there are primarily two types. Standard is the female type connection. The other is the post style.

I suspect the wire connectors, on the plug wires you purchased, were for the "post" style distributor cap.

Prestolite caps seem to be somewhat exclusive to Marine applications.

east tx skier
02-17-2006, 03:45 PM
I'm going to slightly threadjack this in a second. But I've been looking around for plug wires to replace my apparently original factory taylor wires. I went to NAPA who looked up everything based on the information I gave them.

It was only about $4 cheaper than DIM. But with DIM, shipping tends to just add up quickly.

Ultimately, I ordered a set from my local non-MC inboard dealer (for anyone unfamiliar, I do not have an in-town MC dealer). They beat DIM's price by about $9. I think the wires are PCM, but I'm not sure who makes the wires for them. I'm hoping for blue or red, but it was explained to me that Yellow was a possibility. :o

So now for the threadjack. Are distributor caps and rotors marine specific? I'd always thought that marine specific ended with carbs, alternators, and starters. Will I be okay with NAPA if I tell them I have a prestolite ditributor and electronic ignition?

TonyB
02-17-2006, 04:27 PM
Are distributor caps and rotors marine specific? I'd always thought that marine specific ended with carbs, alternators, and starters. Will I be okay with NAPA if I tell them I have a prestolite ditributor and electronic ignition?
Good question. I can't understand why, but there seems to be a marine application for almost every electronic component found on boats.

You can't google "prestolite distributor" without getting result upon result pointing to marine resources.

I did a search on "Magstar wire set" and all the returns were marine.

Why this is, I can't answer. My nearest guess is the the terminals may be of a non-corrosive material in Marine applications (i.e. Stainless terminals).

east tx skier
02-17-2006, 04:34 PM
The typical reason behind something being "marine" is it doesn't cause things to explode. So the carbs are designed not to dump fuel everywhere, while the alternators and starters are designed not to let sparks fly (sealed right?). Or at least so I've been made to understand.

Soon, my local dealer will have a business account with skidim, so hopefully, it'll work out to a better deal for me after the markup and taxes versus what I'd pay in shipping. So far, in many instances, impellers excluded, the local guys can get me pretty good deals.

AirJunky
02-17-2006, 04:36 PM
None of the parts you guys mentioned are marine specific. I've been using Napa parts for all the ignition stuff for a few years with great results.
As mentioned by Tony, you need to get wires with the right boot/connector for your distributer cap & spark plugs.

Things that are marine specific are stuff like the alternator & starter. They are setup so that the sparks inside the windings don't ignite the gas fumes in your engine compartment.

east tx skier
02-17-2006, 04:53 PM
So Bill, for my 351HO, do I just tell them prestolite distributor w/ electronic ignition?

AirJunky
02-17-2006, 05:03 PM
I think I'd bring your old cap in & tell them it's on a boat with a 351, Prestolite distributer & electronic ignition.
When I found all the parts for the 350, I brought the cap & rotor in. The 350 used the same parts for their ignitions for a number of years so it was an easy find.

east tx skier
02-17-2006, 05:29 PM
Well, I just ran down the street to NAPA. We narrowed it down to two, and he told me to just bring the rotor in and he could figure the rest out. I don't want to take all the plugs off my distributor. I'd never get 'em back on right. :o

east tx skier
02-17-2006, 05:32 PM
Just to bring this thread a little closer back to plug wires, there must have been a run on Autolite 764s last year. I couldn't find a complete set last fall and today, NAPA tells me they only have 4. That's 3 Walmarts and two auto parts stores and no joy.

AirJunky
02-17-2006, 05:40 PM
Well, I just ran down the street to NAPA. We narrowed it down to two, and he told me to just bring the rotor in and he could figure the rest out. I don't want to take all the plugs off my distributor. I'd never get 'em back on right. :o
Use pieces of tape to number each wire. Start at 12:00 & work you way around the clock.

Plus..... if all he needs is the rotor, you don't need to pull the cap off. How about taking a digital picture of it to him?

TonyB
02-17-2006, 06:05 PM
Well, I just ran down the street to NAPA. We narrowed it down to two, and he told me to just bring the rotor in and he could figure the rest out. I don't want to take all the plugs off my distributor. I'd never get 'em back on right. :o
Couldn't you just take a single wire (coil wire for example)? Would not that be enough to determine the type of terminal you would need?

The last time I bought wires, I told the parts store they were for a 351 (distributor in front of carbeurator). I got them home and started putting them on the plugs and found they were too short. Evidently, marinization may account for the additional length needed to circumnavigate the exhaust manifolds and risers.

east tx skier
02-17-2006, 07:10 PM
That's why I bought the wires from an inboard dealer who has worked on my boat. It was $5 cheaper than NAPA, too. I think he told me at one point that Taylor made the wires for PCM, but I don't know that for sure.

flipper
02-17-2006, 08:06 PM
I use the "make your own" wires. I had trouble finding wires long enough to reach around the exhaust manifolds. You just cut the wire to the length you want, and put the ends on them. My motor is different from yours, but Ford cap and rotors are all the same for the 351 far as I know. I tell the people I need parts for a mustang because they don't know what to do when you tell them boat. As far as marine parts, I understand that the sparks are part of it, and the other part is that auto parts are not sealed for water. Things like starters sit low and get water all over them.

TMCNo1
02-17-2006, 08:57 PM
Most all ignition cos. ACceL, Malloy, Taylor, Moroso offer universal plug wire kits in various colors and mm sizes, 8mm and up, that come in straight or angle ends at the plugs and include distributor ends for the old style caps and the new style caps and everything to do the job is included including the instructions!. You custom make up your wires to fit your engine. They can be bought through most any auto parts houses and speed equip. suppliers, JEGS, Summit etc. All you have to do is ONE WIRE AT A TIME to keep from futching everything up and in 1 hr. you have a neat job. I have had a set of custom made up wires in yellow since '89 on our '89 ps 190 with no problems, cause it's SO simple to do.

east tx skier
02-17-2006, 10:46 PM
I use the "make your own" wires. I had trouble finding wires long enough to reach around the exhaust manifolds. You just cut the wire to the length you want, and put the ends on them. My motor is different from yours, but Ford cap and rotors are all the same for the 351 far as I know. I tell the people I need parts for a mustang because they don't know what to do when you tell them boat. As far as marine parts, I understand that the sparks are part of it, and the other part is that auto parts are not sealed for water. Things like starters sit low and get water all over them.

At NAPA, I just tell them MC ski boat and they seem pretty comfortable. I think I told someone 86 Bronco once, too.

I've got a speed shop that carries Taylor right down the street, but when I heard there was going to be cutting involved, I decided to just find a set. The PCM wires ought to be fine. They used Ford GT40s longer than Indmar did, and if it turns out they were made by Taylor, so much the better. I'm reasonably sure the P.O. may not have ever changed the wires, so I got 13 years out of my OEM wires, dist. cap, and rotor. These new wires should at least be good enough to last me three years. And they're only $36 for the set.

NSXBill
02-23-2006, 03:52 PM
I used aftermarked "make-your-own-length" performance wires available at most Advance. Pep Boys or whatever. Get ones with 90 degree angle boots at the plug and 90 degree boots for the distributor. Do NOT get the ones for HEI. $40 for 8mm Hi-Perf and you can usually pic your color...

east tx skier
02-23-2006, 10:50 PM
Well, I just found another website that coud get me the same plug wires I just got for $24 plus about 6 to ship them. Food for thought for next time.

Sodar
02-23-2006, 10:51 PM
How often do plug wires need to be changed?

east tx skier
02-23-2006, 11:13 PM
I'm putting myself on an every 3-4 years schedule. Manual lists tune up as annual maintenance. I've also heard anything from 100 hours to 300 hours. My first set lasted me 3 years and apparently, the previous owner got 10 years out of the same set. That's 13 years kids. Not bad.

Sodar
02-23-2006, 11:20 PM
I'm putting myself on an every 3-4 years schedule. Manual lists tune up as annual maintenance. I've also heard anything from 100 hours to 300 hours. My first set lasted me 3 years and apparently, the previous owner got 10 years out of the same set. That's 13 years kids. Not bad.

Hmmm... I might jump on this one before summer.

Workin' 4 Toys
02-23-2006, 11:30 PM
How often do plug wires need to be changed?
IMO 5 yrs....

Sodar
02-23-2006, 11:33 PM
Are there any tell-tale signs of them needing replacement or just another good preventative maintenance measure?

Workin' 4 Toys
02-23-2006, 11:38 PM
Are there any tell-tale signs of them needing replacement or just another good preventative maintenance measure?
Preventative maintenance.
A sign of one "going bad" would be rough running/idle, or a good "short" if the insulation burned. Would run like it had a dead hole.

Sodar
02-23-2006, 11:46 PM
Cool! Thanks WFT!

erkoehler
02-24-2006, 01:35 AM
Preventative maintenance.
A sign of one "going bad" would be rough running/idle, or a good "short" if the insulation burned. Would run like it had a dead hole.


Mine lasted 9 years.

Workin' 4 Toys
02-24-2006, 09:42 AM
Mine lasted 9 years.
Consider the last 4 living on borrowed time.
I suppose they could last 20 or more. But for the few bucks, I don't think its worth the headache.

Maybe I should consider changing them on my Powerstroke...:rolleyes:

ski_king
02-24-2006, 10:00 AM
...Maybe I should consider changing them on my Powerstroke...:rolleyes:
Or on any of the newer vehicles that use coil pack plugs and have a small gauge wire for each plug.

Slight threadjack........
Why hasnt marine engines gone to the coil pack plugs yet?

TMCNo1
02-24-2006, 10:00 AM
I replaced my new original '89's in '89 with ACcel 8mm yellow and that was 17 years ago. If money is no object, just change wires everytime you change plugs, but what's a little OVERKILL as long as your stimulating the economy!

east tx skier
02-24-2006, 10:02 AM
Hmmm... I might jump on this one before summer.

Hey, Cameron, I don't know if there's anything different about the plug wires for the LT1 as opposed to the standard Indmar GM engine, but check out this site. (http://www.whitelake.com/catalog/plug_wire_set_-_gm_1654362.htm).