Single Point System Tune up kit?

Starcraft5834

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anyone used this product? Ive got a 1987 3.0 GM.. ordered Sierra 18-5268 Tune-Up Kit. Its the correct kit for my engine according to the description. Im assuming the point gap is pre-set.. plug and play is my plan.....has anyone used this? am I correct in my assumption? thanks all
 

gm280

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I surely don't know what tune up kit you're referencing, but I can't see how any point gap can be preset before installation on the engine. But I will admit I honestly don't know either... Usually that point gap has to be set via the lobe on the engine to the point rubbing block on the points. But I haven't seen everything and some how I guess there could be some type thing. But I would have to see that to believe it... Points normally get set at .020" after installation. JMHO!
 

ziggy

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yer gonna have to set the point gap. no plug and play w/ points type ign. system. per s/m 10, point gap is .022" or 28*-34* dwell. set point gap/dwell 1st, then timing. point gap/dwell affects timing.
 

grewvin1

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18-5268 is a cap, point, rotor and cond. set for 4 cyl eng. and as Ziggy said you will need to set the points dwell then after that set the timing. Dwell set then timing. Use dwell meter not feeler gauge.
 

wrench 3

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A feeler gauge will do the job, specially with new points, but a dwell meter is better. However you definitely should reset the timing. To get you a specification for the timing we would need more information about the engine.
 

JimS123

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Get rid of that kit and replace the points with a Pertronics electronic ignition system. Its so superior to the old antiquated outdated points that it would be cost effective even at 4 times the price.
 

ziggy

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to ea. his own JimS123.
i'm fine w/ points. my engine was designed w/ using points.
unless i'm mistakin about the only notable benefit would be that i don't have to R&R the points and reset them every year. imho, this isn't hard to do, and when i do it i'm gettin in tune w/ my engine at spring recommissioning.
what i'd be more worried about with aftermarket kit is the dis.cap.
here's a aftermarket cap next to a mercruiser cap.



the cap on the right is a napa cap, i can't remember, but likely a serria cap. they are both marine caps, but the mercrusier cap is notably beefer around the contacts. there was a notable weight difference if i remember right too.

op, do what ya want. but points can work just fine. if ya got em, your oem designed the ign. system to work well with them. i use them and my old boat eng. many times starts faster than my fuelie's w/ elec. ign in my vehicles.
 

Lou C

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In reference to points vs electronic, well, you have to understand that while points need some maintenance, its not even an every season thing. As in, back when I started driving and all cars had points, the spec for replacing them was 12,000 miles or a year. In boating terms that's a lot more than one season. In fact my old boat has points and I have found that they last 4-5 seasons, average. I check the dwell, timing and idle when I re-commission the boat each spring. I also take off the cap and look at the contact surfaces. If they are really getting pitted and burned I change them. I put a bit of cam grease on the dist cam and a few drops of oil in the wick that lubes the mechanical advance and that's it.
If you change from points to electronic, keep this in mind, if the module goes, can you get another quickly? I keep a spare set of points and condenser so I can easily change them and be back in business. Also, the electronic shift assist system on some engines was designed for points, sometimes you have to make changes to that or else the idle will not be lowered when you try to shift to neutral.
 

Starcraft5834

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My plan is to change condensor. Sand the old point which is only one year old but sat since last october..why would engine get out of timing by installing new point in same spot? I would buy a feeler guage and set first ofcourse...
 

JimS123

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I grew up with points. The first 4 cars I owned had them. I had 2 boats with points before I switched. That was 15 years ago and I wouldn't go back EVER.

I used to dress them yearly and replace about every 3 years. As they aged I always sensed a loss in performance, and an improvement when the new ones went in. I ONLY use Merc caps. I agree with the comment about after market junk. The Pertronics works fine with an OEM cap.

I used to replace the caps about every 3 years as well....when there is noticable wear. With the Pertronics I see much better life on the cap. I haven't replaced one in many years.

My tune-ups now involve a plug change....that's all. The timing was set 15 years ago when I installed the Pertronics, and hasn't changed since.

I read comments on this forum about how the Pertronuics eventually fail. I probably should have disregarded that comment, but neverthelesss I bought a new unit and installed it. So, now I have a spare in my toolbox that can be installed in less time than it would take to replace the points. Overall, cost wise, the Pertronics has saved me $ over these 15 years because I have not bought any points or condensers.

Regardless, forget about all that, it's not even important. Some people just like to tinker and adjust. The real reason I'm so sold on the Pertronics is because the motor now runs smoother, has better mileage, and runs consistent year after year.
 

bruceb58

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Don't sand points. Just replace them every other year, adjust with your dwell meter and you will be fine.

Pertronix is just an electronic switch. It does nothing to increase power, mileage or anything else over properly adjusted points. For those that think it improves things, the previous points were either old, maladjusted or we have the ole placebo effect.

As far as reliability goes, I have had 2 friends who have had them fail.
 
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wrench 3

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Around here our winter down time is about seven months, and the points tend to oxidize over the winter. When I was running points I would sand and clean in the spring and lube the cam. One of the main thing is to use a proper lubricant on the cam and rubbing block. With our shorter running season I've gone eight years without the gap changing. But I'm not necessarily recommending that you run a set for that long.
As for resetting the timing, the points are not that precision made. Even a slight difference in the width of the rubbing block will change the timing.
 

Silvertip

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Take it from us old-timers. You MUST check and reset timing when you change or re-gap points. It is very simple physics. Dwell (point gap) affects timing, but timing does not affect dwell. Sort of like all thumbs are fingers, but not all fingers are thumbs. (Yes -- that's a quote from the Big Bang Theory.)
 

JimS123

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Don't sand points. Just replace them every other year, adjust with your dwell meter and you will be fine.

Pertronix is just an electronic switch. It does nothing to increase power, mileage or anything else over properly adjusted points. For those that think it improves things, the previous points were either old, maladjusted or we have the ole placebo effect.

As far as reliability goes, I have had 2 friends who have had them fail.

The last tune-up I did with points went fine until half way through the first day out when we were far out in lake Erie. Complete ignition breakdown. Naturally, that's why many of us run kickers. We got home just fine. The next day on the muffs back home she ran fine again.

Short story long.....by process of elimination I found out that the brand new condenser I bought for the tuneup was defective. The marina parts maager said it was a one in a million shot. Just my luck.....LOL.

My Pertronics was trouble-free for 15 years. I know of another one that has over 20 years on it. The fact is that every product has a few that are defective. Naturally, the bad ones are the ones you hear about.
 

bruceb58

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There is a reason that older airplane engine still use points and that, as far as I know, there are no aftermarket modules similar to Pertronix approved for them. I would go with the one in a million condenser failure.
 
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