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Briggs Help


maxtorman1234

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maxtorman1234
I cant seem to get the 16HP briggs i got to run right. Every now and then it will run real rich and try to stall, even when im just driving around and its not working. I have tried 2 different carbeurators on it, and its not the carb, theres something wrong with the engine it'self. Im wondering if it could be the valves, ill have to check them. this does not have points, so maybe the spacing for the coil is not set right, does anybody know what it should beset at? Thanks,
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Briggs uses a large variety of governor springs. Along with Kent and Ron's suggestions you may check that as well. Even the adjustment on the governor can be off a little and cause trouble. I've had the wrong spring on and got good response when the engine was on the cooler side then BAD attitude with it warmed up. It wanted to govern with out needing to be governed which made it act as though it was running too rich with out the black smoke. Just my two cents worth. Have you gone to Briggs.com and downloaded the PDF file for that particular engine? Let us know what you find out!!! Sean aka Zippo
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Valves are a possiblity, but I'd be more inclined to look for weak or intermittent spark. An intermittent spark will act like running rich. Spark misses for half a dozen revolutions and the engine is still drawing in fuel. Spark finally hits, but fuel is so rich in the cylinder that it acts as though it's flooding. Even a weak spark plug can cause this condition. Try a new spark plug first. If condition persists, get an inline spark tester and run the machine while observing the spark. You'll be able to spot the misses if that's the problem. Pat
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Robert Kehoe
I just tore my 2110 down and it was the head gasket from overheating because it was cloged with grass. the exhaust valve was somewhat bad also so i replaced it while apart. Goes back in tommorow so i hope it works...
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Pat, I agree to a certain extent. If the valves are working properly there will be no build up of fuel, as the exhaust valve opens it will expend the unburned fuel as it would if it were running correctly. The engine will act as though it would with a proper spark only it would seem powerless intermittently. Your explanation wouldnt explain a rich running condition, it would explain an intermittent ignition problem. Which would point to the points, which has already been discounted, so the possibility of a bad spark plug then comes into reason. Which would cause a weak spark if it is partially fouled. On this account....a high rpm would increase the spark and therefore help the partially fouled plug with the burn off of the carbon build up. I suggest pulling the plug and checking for a cigar colored tip. That's a proper appearance with a visual inspection. If the plug end is wet or covered with black soot then you have a rich burning condition that can be attributed to advanced timing, improper carb adjustments or a mis-aligned governor. Another consideration would be the magneto and coil are not gapped correctly or have a coating of rust built up on them which would cause a weak spark. All this is based on my experiences over time and intended only as a suggestion to cure the cause of your troubles. I hope you get it worked out soon. Sean aka Zippo
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Is this a twin or single? Coil spacing should be set at beercan. Cut the ends off an aluminum can and flatten it out. Non magnetic too. That is the equivalent to, if I remember correctly, .020
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Jovee, I've used business cards for as long as i can remember also. With todays aluminum cans you can get as thin as .08. Business cards are a pretty consistant 18-22 thousandths. Sean aka Zippo
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I would have thought business cards would be a tad thick but if they work, then they're another option. But I bet its more enjoyable making new aluminum gauges -lol
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quote:
Originally posted by Jovee
Is this a twin or single? Coil spacing should be set at beercan. Cut the ends off an aluminum can and flatten it out. Non magnetic too. That is the equivalent to, if I remember correctly, .020
Redneck feeler gauge?:D}:):o) Elon
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Well let's try basics. I was told at one time and Al Eden can correct me, but 95% of most cranky hard starting, funky running and so on can be corrected by replacing the spark plug. This applies to all L & G engines. I try and avoid checking spark with a plug, but use the Briggs spark tester. When correctly adjusted, the gap is .166", about five times the required plug gap. Also on the second screw and ozone layer is created when the spark jumps the gap to simulate a plug firing under compression. I have had my tester for twenty plus years and when someone has a problem similar to Grahm's I check the spark and try a different plug. This handles most problems.
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Sean, I understand the theory that unburned fuel will be expended due to the exhaust valve opening as in a running engine, but the burned gases are expended easier and more completely than raw fuel. Customers have asked me this question before in similar situations. The easiest way to explain it, is if the raw fuel is expended as the burned gases are, it would be nearly impossible to flood an engine. Yes, intermittent spark CAN appear as an over rich carburetor condition, complete with black smoke from the exhaust. Pat
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Thanks Pat! With all the information that Max is getting he's sure to get the problem resolved in no time. I guess another thing I failed to ask was if this is a vert or horizontal. I've seen more verticle engines suffer this type of problem than horizontal engines. We had a post on this recently about the poor reliability in the newer briggs carbs. Jovee, I have my fair share of makeshift tools including tin can bottoms that I use for the plug holes in the ends of briggs carbs. With them being cupped you can tap one into place and it stays just like originals. I have one that's been on a 7hp briggs for about 8 years now. Cut the tops off and you have a real handy portable small parts washer and keeper during a tear down. Then there's the ever popular shim material as you mentioned. Necessity is the mother of invention!! ;-)
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maxtorman1234
Thanks guys, this is a horizontal cast iron briggs single, Model 326437 It was said to have been just rebuilt, and it has been bored 0.010" over, and has a new piston installed. The cylinder looks really nice, but when i speed up the engine i get lots of blue smoke as well, when i pulled the head off, it was full of oil. I think i will take it apart and check the rings. I also decided to check the valves, theyre supposed to be .017-.019, but i can fit a .021 feeler guage between it. and the intake, 0.007 to .009 and a .011 feeler guage fits between it. so whoever rebuilt this thing apparantly does not know what they are doing. If this were a kohler i would simply adjust them, but since its a briggs i need to go and buy 2 new valves, not happy. Dave, thats why i like the kohlers with adjustable valves we were talking about a while back. thanks to everyone for the help, but im pretty sure its the valves causing my troubles, thanks
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Ronald Hribar
The reason Kohlers have adjustable valves is that they are getting repaired all the time. If someone "adjusted" the Briggs valve incorrectely by grinding too much off, you can not blame that on Briggs.
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Graham, Don't trash the valves just yet. A little off might cost you some top end performance but it won't cause the smoke and other stuff. Just cause the valves to open later and close sooner. If it's smokeing like you say, check the valve guides for wear and the rings for alingment like you mentioned. Might be the bore wasn't cleaned properly after honeing and debries has ground up the new rings. Also, since you don't know how capable the other person working on it may have been, put the piston in the bore without the rings and check the accuracy of the bore. They may have gotten it off. I still think your dealing with multiple problems here and it must be addressed as such. I still think you have ignition problems separate from the smokeing issues.
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maxtorman1234
Ok, i'll have to take it apart and check then i'll deal with ignition problems if theyre still happening. I'll check the coil gap, but i really didnt want to have to tear it apart. Thanks guys, i'll check the rings then other stuff and get back to you,
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Grahm, .002" extra doesn't really mean that much. Over time they will hammer in closer. Don't waste good money buying new vales. You can reface them and get closer also.
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Zippo - Good idea (welch plugs - one to remember) Ron - Good point! Graham - Good luck (Dave has got you covered)
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While you have it apart, be certain to check the ring gap in the bore.. If the shop mechanic did not know what he was doing, he may well have not cleaned the bore completely. The debris not only builds up around the rings, but wears them prematurely. You may have a set of rings doing nothing at all but pumping oil into the compression chamber. I'll agree with Dave, check the valve guides for wear. Your problem sounds like the culmination of several problems, not simply one thing or another. And...Watch it with that redneck feeler guage garbage! I may be a redneck, but I do own and use feeler guages!!
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maxtorman1234
well, so far I have taken the engine apart, and found that the rings werent put in quite right. I still have to check the end clearance, before i put the piston back in, but i also checked the clearance between the coil and flywheel and it was almost non existant. I can see on the flywheel where the coil was rubbing almost all the way around. So im going to set it but you guys tell me .020 and my briggs book says 0.010 to .014. Which should i set it at? thanks
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The mag clearance is just NOT that critical. Best bet is go by the book. But vissible air gap is really what your looking for. Keep up the good work, your on the right track.
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