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Excessive Blow by Front cylinder only

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Derf40

New Member
My bike 1997 Softail Custom, has been parked inside for 10 years. After starting, the front Cylinder has excessive blowby thus feeding oil into Carb.. Compression is the same on both cylinders 121 lbs. (by my gauge) the plugs appear to be clean. What could be the problem?
 
Oil drained out of tank??? Start with a fresh oil and filter.
 
Derf40 said:
My bike 1997 Softail Custom, has been parked inside for 10 years. After starting, the front Cylinder has excessive blowby thus feeding oil into Carb.. Compression is the same on both cylinders 121 lbs. (by my gauge) the plugs appear to be clean. What could be the problem?
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I Drained the tank and installed a new filter, and new oil, before I even tried to start it.
 
How much oil did you drain out. There could have been a lot of oil in the lower end and is now being pumped back through the AC. It's called sumping.
 
I'm not knowing what the umbrella valve is nor where it is or what it looks like. I drained the oil from the tank there wasn't much in there at all. I've run the bike for maybe 45 minutes the oil is now black which I figured was from the oil in the bottom of the engine but I looked for a plug under the engine and didn't find one, perhaps because I don't know where it would be or what it would look like. I had thought that there might be a strainer on the return side of the of the engine and the tank but I have no idea where it might be if there is one. The bike ran perfect when it was put up and I put it away. Not of my choice though.
 
The umbrella valves are in the rocker boxes and they might be shot. I'm thinking the oil drained into the crankcase and when you drained the oil and added more the excess oil had no place to go but out the AC. I would drain the oil again and turn the motor over and the oil that might still be in the crankcase will be pumped back up to the oil tank. You will need a manual so that we can help you get your bike back up and running.
 
I did have a Manual 10 years ago I haven't found it yet. I haven't searched all the boxes that were stored yet I'll do that tomorrow morning, while the attic is cooler. I appreciate all the help I can get. I have never used a community help service before on anything so this is new to me
 
There are many members here and we will be here to help you get back in the wind. Since the bike was put up running well it should be back on the road pretty quick. you need to make sure there are no problems inside the gas tank and that all the hoses are in good shape. You will also need to drop the float bowl on the carb and clean all the varnish in there, and put some Seafoam in the gas tank to clean the carb.
 
wrenchin said:
Whenever a problem arises on a bike, it's best if you can supply all the info you can on what has been done to the bike , any modifications and what you have tried instead of just asking a question of "what could be the problem"? We can only help if you give us the info mentioned above and as much as you can furnish right in the beginning otherwise it becomes a question and answer thread and nothing is accomplished at all for many replies.
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Like I say can not help if we do not know.....................
 
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