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Briggs question


goatfarmer

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My latest aquisition is ticking me off!}:) The 12 HP Briggs on my 4212 has a LOT of blowby.The tractor itself is in great shape,doesn't appear to have a lot of hours on it,however it's also a 1990,so anything is possible. Before condemning this engine,is there something that I'm missing that could be causing it?It supposedly sat for about a year before I bought it.Could it be a stuck ring,that might free itself? Or is it just worn out? TIA
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Is that the tube that runs between the carb,and the engine? It's clear,that's one of the places I noticed the blowby.Also when I took off the oil fill,it was puffing bad.
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quote:
Originally posted by goatfarmer
Is that the tube that runs between the carb,and the engine? It's clear,that's one of the places I noticed the blowby.Also when I took off the oil fill,it was puffing bad.
As in puffing blue smoke or just making a lot of noise? I would say run it hard for a while and monitor your dipstick level and then later your spark plug for built up oil deposits. If no build up is noticed, run it.
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If it happens to be a stuck ring you can do a couple of things to maybe help. Start the engine and run till warm, add about 1/4th cup of fuel injector cleaner to the crankcase oil. Re-start the engine and allow to run 30 seconds or so and shut it off. allow to sit 10 minutes and run for 30 seconds again. If you do this 4 or 5 times and don't see improvement, Its time to look at a rebuild. Couple of other things to look for BTW... Check the top and bottom crankshaft seals.. If they get weak, they will draw air in faster than they push oil out so you will get crankcase pressure that acts almost exactly like blow-by. Good luck and let us know what you find
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quote:
As in puffing blue smoke or just making a lot of noise?
As in puffing out copious amounts of oil through the carburetor vent tube,and out the oil fill.I just rebuilt the carb,but can't get it to stay running long enough to adjust it.Makes an oily mess everywhere,too.:(!
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Kenny, Once the paper air filter is oil wet, it make the engine run like its choked all the time. Not only that but the filter being behind the vent tube, Raises engine vacume and can cause a problem that feeds itself.. Most times when I have run into this problem one of 2 things caused it. Either the engine had to much oil in the crankcase, or the float in the carb had stuck and gas had bypassed the piston rings and gotten into the oil. Again overfilling the crankcase. You can smell the gas in the oil if this happens to be the trouble. Again, good luck..........
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Crankcase definately not overfilled.And it's running without the air filter assembly in place.I'm going to pull the carb back off,so I can get to the breather.Won't be 'til next weekend,though.
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If you take the breather off of engine the fiber disc if it is that style should rattle and the 2 little holes on the edge of one side of the inside edge of breather plate should go downward or breather can not drain and you could get the problem you are describing another thing is worn Valve guide or guides as well as possible rings. do you have access to a Cyl Leakage tester?? if so that would show you what is leaking by and at what % the leakage is are you in wisconsin? If so I could try to give you some help as I am near Port Washington good luck Jim
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No,South Bend,IN.I plan on pulling the head,and looking for obvious damage,like a scored cylinder,cracked piston,etc.
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Goatfarmer, The filter you want to check is not the air filter but the positive crankcase ventilation filter. If it doesn't rattle you can have problem similiar to you describe. I know someone posted once before about oil comsumption. You might want to do a search. Also, others in the past have put ATS in the top of the block through the plug hole and let it sit for 24 hrs. Thi has loosened up stuck rings. Stan
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I'll give it a check.But like I said,I don't relish pulling the carb back off to look at the crankcase filter.ATF in the top end sounds like a good idea,also.
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Kenny, I'm glad you figured out I meant ATF and not ATS. I'm not sure if it's the wireless keyboard or those 3 words a minute fingers flying so fast I can't control them
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I had this problem with a 4hp. last year,it was the exhaust valve,,,so carboned up it was stuck open just a little,but enough to cause oil to get pulled up the valve stem.
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