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Carbs and Fuel System
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Thread: Oil in the air breather.. Reply to Thread
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08-16-2017 08:52 PM
Jdjb021970 Just wanted to give an update, I found a good used set of pistons on eBay for pretty cheap too only 30.00 with less than 7000 miles on them so wish me luck that this solves my problem. I still have to get new valve seals and I'm praying I don't have a bent valve. Guess I'll find out when I get it torn down.
08-12-2017 08:45 PM
Spockster I get the best prices on ebay, but you'll have to watch for while maybe to find new pistons, I do recall seeing some in the past month or so. Did see a piston and cylinder in a couple of listings today, used.

I do love my ebay account, have a long list of parts and dollars saved from there.
08-11-2017 09:27 PM
Jdjb021970 OK so I checked the two emission tubes, one of them has a rip where it connects to the valve, I pulled the plugs the front two are burning nice and clean the rear two had oil on them, I checked compression with my thumb the front cylinder pushed my thumb away, the rear cylinder barely had compression, could this be why it's pushing oil up and out the crankcase breather tube at higher rpms. I shined my flashlight thru the plug holes and I can see the valves going up and down. But I know that doesn't mean they are opening and closing all the way. Where would be a good place to buy new pistons and rings at a reasonable price.
08-08-2017 09:37 PM
Spockster Pull a plug from each cylinder and see if one is oil covered, that would be the cylinder to check compression on first.

Looks like the pressure increases dramatically with rpm, I'm still thinking piston/ring/cylinder/valve damage.
08-08-2017 08:29 PM
Jdjb021970 I pulled the crankcase breather tube from the air box like I said above it does feel like there is positive pressure in the tube, it only leaks the oil from the crankcase when I Rev the engine up. I can let it sit at an idle long enough to let it completely warm up and for the fan to come on and go of several times and it don't push any oil out the crankcase tube until I rev the engine up. I'll try checking the other two hoses coming off the side of the heads and let you know what I find. I'm starting to think I might need to pull the motor and tear it down and see of there is something internal messed up. I'm just having a hard time believing it's internal like pistons with it running as good as it does.
08-07-2017 10:20 PM
Spockster I doubt he needs to check the carbs any further.
08-07-2017 10:10 PM
One1 Here is a few things to mow over from the repair manual. Start with the hoses, move on to the carbs. No need in tearing into an engine when you can do simple diagnostic tests. Find the source of the issue, go from there.
08-07-2017 10:06 PM
Spockster Don't think that much oil in the intake would come from being overfilled. It's pumping oil. And you're not going to see oil in the emissions hoses unless the head is cracked open.

08-07-2017 10:04 PM
One1 Next order check these. Theres only a few spots this could be coming in. Find where it's happening first.
08-07-2017 09:55 PM
One1 Its smoking because the intake is filled with fluid. The fluid inundated the pods, tubes, snorkels, etc. there's going to be plenty in there to blow out, drip out, drain out...... so it would be expected that after it was overfilled it would still be cleaning itself. Let's assume you have solved the initial problem of it being overfilled (we will work on why later). From here disconnect the tube from the bottom of the airbox behind the radiator coming out of the engine and see if it is gushing or not. That's easy and tells you if thats where your oil is coming from.

I know you said you pulled a tube, but this issue may happen at different rpm, etc and needs further testing.

Edit: after you remove this tube and the two below you need to pull the carbs and see what it looks like inside the intakes
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