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MisterB

How to set points/timing

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MisterB
After completing the magneto to battery ignition conversion on my 7014, I've noticed that the breaker points are wearing faster than normal despite the limited use since the conversion was completed. I found a link here to a device called "The PointSaver" which should in theory eliminate the excessive pitting by removing the higher current running across the contacts. http://www.kirkengines.com I have the pointsaver installed and the installation instructions suggest installing new points (the consenser is no longer needed) when the pointsaver is installed. I'd like to be as accurate as possible when installing the new points so I'm looking for the most accurate method of gapping them. Which would be the most accurate method: 1.) Feeler guage @ .020 2.) Ignition timing 3.) Dwell angle I don't see any timing marks on the engine, so I'll assume that they're on the flywheel. Also, this device has an indicator light to do a static ignition setting. How would I do that?

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wminmi
i set the point gap with the feeler gauge. no problems as of yet. As for the "pointsaver", it's a NICE replacement that works awesome! I haven't done it to the Briggs engines yet, but have installed a few on the Wisconsin engines i used to run and they worked perfectly, no more wasted points! As for the light deal, can't help ya there as that's a newer feature, mine didn't have that :(

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MrSteele
Feeler gauge. I usually use a small piece of the box that the points came in as my gauge. Have been doing that for years, and there is no risk of oil left on the gauge to cause problems.

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D-17_Dave
A dwell meter is the only true way to set a points gap accurately. But it's rarely neccessary on these small engines. You can use a timeing light on these engines buy removeing hhe air shroud and running the engine at low rpm's for a short time. There is an arrow on the front of the flywheel on the magnet mount faceing forward. I forget where but I think the other mark is on the magneto mount on some and on the magneto on others. One thing to remember is the closer the points gap the sooner the timeing so ste the points gap first then set the timeing. Be carefull of the spinning flywheel and cords and don't run the engine too long as it has no air flowing over the cooling fins with the cover off.

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HubbardRA
MisterB, If the points were getting a burr on them faster than normal (I assume this is what you meant), that would likely mean that you do not have a ballast resistor in the circuit. The ballast resistor drops the operating voltage to 6V. With 12V across the points, they will burn many times faster.

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PatRarick
quote:
Originally posted by HubbardRA
MisterB, If the points were getting a burr on them faster than normal (I assume this is what you meant), that would likely mean that you do not have a ballast resistor in the circuit. The ballast resistor drops the operating voltage to 6V. With 12V across the points, they will burn many times faster.
That is my assumption as well. Learned that many years ago when as kid, I converted my 53 Chevy to 12 volts. Burned out a set of points every 200 miles until I learned about ballast resistors. You either need a ballast resistor, or a coil with an internal resistor. As to timing, on the single cylinder cast iron Briggs, the points are to be set at .020". There is an arrow on the flywheel, and another arrow on the coil mount. These arrows must be in alignment as the points just break (open) With the point gap set at .020, you disconnect the wire for the condenser and the magneto from the points. With a test light or an ohmeter connected to the terminal on the points, and grounded to the block, turn the engine in the running direction (clockwise at the flywheel) of the engine until the points just open. Depending on what you are using, the points open at the instant you read 0 ohms, or the test light goes out. At that precise point, the arrows of the magneto mount and the flywheel should be in alignment. If adjustment is needed, you will have to remove the flywheel and loosen the coil mount screws just enough to where you can move the mount by lightly tapping it. Reinstall the flywheel, align the timing marks as the points just break, then remove the flywheel, tighten the screws, and reinstall the flywheel. On Kohler engines, the point adjustment is what sets the timing. There is a mark on the flywheel that has to correspond with a hole in the blower housing. You hook up the ohmeter or test light as described for the Briggs engine, and align the marks. Close the points and then open them to just break. You can also use a timing light, but I've found it difficult as the engine vibrates enough that it's hard to keep a screwdriver on the points to set them. Pat

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BrianP
Wow, guess I take the easy way out. I long since converted over to an automotive type coil (with built-in resistor), and the engine doesn't even make one revolution before firing up due to hotter spark. I did this rather than yank the engine, set up a new magneto and re-assemble everything. After my second mag replacement, I looked for a better way. What's of real interest is this condensor eliminator. I think I'll try one on my 3410, which has been sidelined all summer for an intermittant spark problem. I think a bad condensor is the culprit. I set my gap by loosening the "jam nut" and (with plug wire off), crank the engine while turning the point adjustment screw with a screwdriver. When I get a nice spark, I stop cranking and lock everything down. Whenever I tried to set the points using a feeler gage, it did not always work. I figured there was wear on the plunger tip that threw off the measurements.

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rsnik
Back in the days of points, like on my 66 chevy pickup, I could insert a long flex tool into the the hex socket on the distributor that let me adjust the points while standing in front of the vehicle with the engine running. A real good (like Snap-on) dwell meter was the only way to go. I had a good meter that would show points bounce at higher revs if the points you bought were not the best. If you don't have the ability to dial in the point setting with the engine running a feeler gauge is probably more efficient. rsnik

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firefoxz1
Pat: you explained setting the magneto timing (syncronization) perfectly but in this case it is mute and void as he is not running the magneto. There would be no way of adjusting the timing with an external coil other than adjusting the dwell at the points as in Pat's description for the Kohler engines. Finding excact TDC on a Briggs would be a little more trouble, no actual marks that I know of.

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MisterB
quote:
Originally posted by HubbardRA
MisterB, If the points were getting a burr on them faster than normal (I assume this is what you meant), that would likely mean that you do not have a ballast resistor in the circuit. The ballast resistor drops the operating voltage to 6V. With 12V across the points, they will burn many times faster.
I used an internally ballasted coil when I did the conversion to avoid having to add either a ballast resister or resister wire. Just to be safe, I did check the coil to make sure there was at least 3 ohm of resistance across the terminals. My understanding is that the voltage isn't what causes the points to erode so quickly but rather a combination of voltage and amperage.

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MisterB
quote:
Originally posted by firefoxz1
Pat: you explained setting the magneto timing (syncronization) perfectly but in this case it is mute and void as he is not running the magneto. There would be no way of adjusting the timing with an external coil other than adjusting the dwell at the points as in Pat's description for the Kohler engines. Finding excact TDC on a Briggs would be a little more trouble, no actual marks that I know of.
I've suspected for some time now that setting the dwell was going to be the most accurate measurement of point gap. It seems to me that there will now be a direct correlation between ignition timing and point gap settings, correct? Is there a way to calculate what the corresponding dwell should be given the recommended point gap of .020?

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firefoxz1
It is the dwell that you should be looking for, the gap setting is just to get you close, atleast that is the way it was for cars. Can't say I have ever seen a dwell listed for these engines. I read the site for the pointsaver. Sounds like it would be worth it for atleast my Sears with the point eating Onan in it.

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HubbardRA
The only way to determine the dwell on that specific engine is to measure it. Dwell is the number of degrees of crankshaft rotation (during a single engine revolution) that the points are closed and causing the coil to charge. It is determined by the size and shape of the flat on the crankshaft or camshaft that the points are triggered from and the point gap that is required to produce the proper firing arc. They both play together to produce the correct dwell angle. Since the size of the flat on the shaft does not change, then proper dwell can be established by setting the proper point gap. Use of dwell meters became more of a standard for mechanics when Chevy developed the small block V8 with the distributor on the rear of the engine. It was nearly impossible to get to the points on that engine with a feeler gage to set the gap. Use of a dwell meter, combined with points that were adjustable with a hex wrench while the engine was running, made setting of this distributor much easier. If a person puts in a new set of points and knows for sure that the gap is set perfect, then he can measure the dwell with a meter, and use that reading to set the points with from then on.

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