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7.25 hp troubles


henroan

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Hi everyone. Need some advice on my 725. I replaced my head gasket and now for some reason I cant adjust the carburetor for high idle. It works fine at low idle but at high It just sputters and blows out black smoke. I know that black is gas but even if I adjust lower carb jet to only half turn out it does the same thing. I thought of timing so I replaced mech. points with elect. module but no change. I'm stumped. Any help would be appreciated. TIA Patrick Sorry for not posting in a while, Ive been very busy and poor. Now I'm trying to get this ready for plowing this winter.
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Try replacing your plug. It is easy to get carbon fouled during a head operation. Usually if you are getting black smoke and sputters it is a derivative of misfiring. Sometimes it is from starvation of fuel.
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By your description it is a carb. issue. I would start by going through the carb. then try readjusting it to 1.5 turns out from seat. The only place "BLACK" smoke comes from is unburnt fuel.
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Check this out. There is also mor info on smokestack.com Search for model 19 ignition http://gasengine.farmcollector.com/gas-engines/Cheap-Fix.aspx
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OK Nicholas, you just made my decision harder. I have been having the same problem with my Model 19 and had concluded that it was the ignition coil. I was about to order an aftermarket replacement and stick it in. After following searching the Smokestak.com site, I read a number of posts that indicate that even the NOS original B&S coils are problems and go bad just sitting. I believe I read that in the SimpleTractors archives as well. Has anyone had any luck (good or bad) with an aftermarket replacement, or even with a NOS Briggs one? I would love to hear several people say that they have had no problems with using an aftermarket coil. Has anyone tried the modification of a coil as described in the link? I would not be afraid to try it, but it will probably cost me as much as an aftermarket coil by the time I find new or used coil to modify and spend a bunch of time messing around with it. If I had a used coil sitting around, I would probably give it a try. Glen
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I am in the same boat as you guys, thats why I found this info. I actually think that the motor I have has good ignition....now. I plan on cleaning up the tractor and motor and then painting it all. problem is, if these coils go bad as often as it sounds, I dont hink i want to install it unless I replace the it myself with this method. I would hate to tear an engine out of a freshly painted tractor. I am not sure but I think any of the Briggs coils that are usable are under $40 new. That is prob less than a NOS one for a model 19, and that may be bad anyway. i am thinking we would all be ahead if we just changed out the coils. Then we would have no doubt that we have good coils for a long time.
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Turned out to be carb. Had 3 different carbs that I tried. Mixed and matched all parts of those carbs to find 1 good carb. To no avail. Removed motor from chassis. Mounted onto bench. Bypassed internal coil with external coil. No luck. Same problem. Replaced condenser. No change. I was stumped. Finally, removed 4th carb off running snow blower. BINGO. That was it. Why does it have to be so hard?
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I have no idea, dentwizz. All 3 carbs were the same model. You would think that with 3 different carbs you could put 1 good carb together. After changing seats, needles, jets and different bottoms and tops just didn't find the right combo. I even had a rebuild kit, so I had 4 sets. The first carb I tried to rebuild. The other 2 I did not. My mistake. Worked on it for about 3 hours. I still have all carb parts so maybe at some point I can come up with 1 perhaps 2 good carbs. I certainly don't want to buy these things. Their awfully expensive. I,m not a mechanic, dentwizz, I wish I could help more. I'm am getting better though. Patrick
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