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Hey guys, I decided to check my valve clearances as I could hear a ticking as the motor ran. they weren't bad but decided to adjust to get the hang of it. so hear goes:
1. when I pulled the valve covers off there was oil up in the covers is this normal? same for both and then I realized you fill the oil in the front so maybe it is.
2. when I reassembled she smoked like crazy. I checked the gaskets and they weren't seated correctly. After I reseated the gaskets 98% of smoke gone. I also had quite a bit of oil up in the carb and air filter is this due to gasket mishap?
3. when I pulled the plugs, the front had carbon on it but not as bad as the rear plug. neither was wet but both black. Is this okay to have one plug dirtier than the other?
I need to get a new sealing washer for the cover nut but running with only three of these on and the fourth just the nut, would this be a source of smoke, very minor smoke?
Were you using oil or noticeably burning oil before you did any of this work? Do you have oil sludge on the top of the engine or on cooling fins below heads? I know you said most of the smoking is gone now...but I'm curious if you're using oil. The plugs shouldn't be black. If it's running fine, it just depends if you're okay with the situation. I would do the standard compression test (leak down test would be even better). If you are getting a lot of blowby (from the breather hose routed to the air cleaner), you might just have a head gasket problem. This will definitely make you use oil (may or may not smoke), and it will pressurize the crankcase via the pushrod creating quite a bit of oil vapor from the breather hose. The head gasket is always a likely culprit, especially if you've overheated the engine or "backfired" frequently on shutdown. I finally just started killing mine with the choke, as nothing else would prevent it.
Did your valves need much adjustment? Sometimes a cracked muffler can cause some ticking too.....just a few thoughts.
well, lets see. 2001 argo bigfoot, B&S 18 hp 180 hours on it. should have mentioned this to begin with. This is what started the whole thing.....Member Kezef tuned the motor and adjusted the idle mixture and she purred and shifted smooooth. that was this fall. on new years day I had my nephew out in it zipping around non stop for about 15 mins in high gear. I got in to go in the swamp so we drove a little and before the mud i stopped and tried to shift into low. as I did I heard a loud pop and then I had to shift with the choke on, like I had to before Kezef set the machine right. after the pop I could shift with choke but the machine was under powered, so decided to go back and trouble shoot. I have to climb a small hill to get home and I wouldn't climb it and the motor would stall. tried several times and no luck. restarting and the motor was purring nice but under powered and very hesitant on the throttle. When I got out the machine had enough power to carry my nephew and we nursed her home. on level ground it could carry both of us but weak and hesitant on the throttle. Same situation high/ low and reverse and idled great. I thought it a clutch issue so when I had time I started her up and she purred but a ticking now, kept her in neutral and throttled to check the clutches. Clutches worked fine but hesitant till warmed up. I thought the ticking was now the valves, I am no mechanic. So that's when I went into the valves. Push rods were in and straight, took each out. one valve on each head wasw tight for .005" gauage. so I set them all to .005" and re assembled. Now she smoked and was blowing oil. I adjusted mixture and nothing so set back to ! turn. I pulled the valve covers and both gaskets weren't seated right. resolved this and 98 % of smoke gone. she' purring the whole time at idle and no real power loss. I ran her in the yard yesterday a bit and smokng out of the exhaust some in the beginning but after about 5-10 minutes no smoke and idle goo and throttle response good. ticking is there and consistent after warmed up. I have to get a new seal washer for the valve cover today as i dropped one into the tub and is now gone so I'll check the valve adjustment again before putting covers on. I think the blowing oil was bad gasket seating and then some oil in the carb till burned out. ther is no oil on the motor at all except at the dip stick hole. she purrs at idle and is responsive but starts to tick when heated up, something i will monitor today. Mayb it is a cracked muffler? when I pulled the plugs to check 1/4" fromTDC is when I noticed the spark plug fouling and the difference between the two. Both have spark, front looked normal to me but the rear plug was much more black and neither was wet. thanks for the help Buzz and I'm open to suggestions.
You might notice sounds when your motor is running rough that go away when it's running smoothly. I would start with at least a compression test after you've warmed it up. Of course it's hard to envision from a distance, but it sounds like it runs good at times, and at other times not so much. Make sure you don't have it choked when it's running...that would definitely make it smoke and fall on its face under any kind of load. Make sure you have no obstuctions en-route to the carb, for example fuel-shutoff solenoid under the carb. If so, unthread it, remove troublesome plunger, re-thread (without plunger) and remove wire. I'd have to look up whether you have a diaphragm fuel pump or an electric fuel pump, but you'd want to make sure they are pumping to spec (psi). I've seen some crazy smoking and loss of power when the gas-level in your tank starts getting low. You can move on to the carb (if need be) once you confirm a few of these things.
Thanks for the help Buzz, I'm riding with Kezef tomorrow and I see if it acts up. I'll post more after that, thanks. I'm going to check the muffler for movement, if it's the ticking. like I said it really runs well all the time, this was just a peculiar incident that I just want to fiigure out for piece of mind.
valve clearances are .004, check ur rocker arms for cracks and bent flanges on them along with ur push rods. cracked rockers are a big problem with vangaurds
thanks Chris, pushrods were the first thing I checked and all 4 were good and straight. I also looked over the rocker arms and all was good there also.
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