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Oil-drenched engine

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  #161  
Old 04-27-2015, 09:52 AM
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No smoke at all, it doesn't even fire up at all... Haven't pulled the plugs yet, but I am about do that and check for spark and compression. What I did pull was the carbs because they were leaking good. So I guess I'll have to go through them properly again and check all those old, tiny o-rings among other things.
 
  #162  
Old 04-27-2015, 09:56 AM
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Where were they leaking from?
 
  #163  
Old 04-27-2015, 10:19 AM
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Check the compression. The motor sounds a bit off to me.

Did you turn the motor over and verify the cam timing?
Did you have the ring gaps lined up like in the picture when you put them in?
 
  #164  
Old 04-27-2015, 10:29 AM
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I believe they were leaking from the fuel junctions between the carbs but I'm not sure.

The sound is a bit distorted by the phone though, could that be it? I turned the engine before starting and as far as I could tell it turned as it should. Same goes for the rings. Would compression fail in one cylinder mean the others would fail too?
 
  #165  
Old 04-27-2015, 10:34 AM
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Originally Posted by 74demon
Check the compression. The motor sounds a bit off to me.

Did you turn the motor over and verify the cam timing?
Did you have the ring gaps lined up like in the picture when you put them in?
This pic. I'm interested too.




Originally Posted by Migge
I believe they were leaking from the fuel junctions between the carbs but I'm not sure.

The sound is a bit distorted by the phone though, could that be it? I turned the engine before starting and as far as I could tell it turned as it should. Same goes for the rings. Would compression fail in one cylinder mean the others would fail too?
It seemed like it was spinning really fast. Was it a brand new battery?

And no, one could fail a compression check, or they all could. Generally, if only one was too low on compression and the others fine, you'd have a constant misfire.

But the reasons for low compression could be many.
 
  #166  
Old 04-27-2015, 01:22 PM
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Now I follow. I don't think I put the gaps on top of each other, but I am not sure about that either. Then it would mean a higher risk of not getting any compression, right?

The battery is pretty old and not even fully charged but still gives a good kick. But when talking about speed, I took another video where you can see the valves moving. It doesn't look superfast to me...

Movie
 
  #167  
Old 04-27-2015, 02:16 PM
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Originally Posted by Migge
Now I follow. I don't think I put the gaps on top of each other, but I am not sure about that either. Then it would mean a higher risk of not getting any compression, right?

The battery is pretty old and not even fully charged but still gives a good kick. But when talking about speed, I took another video where you can see the valves moving. It doesn't look superfast to me...

Movie


Its pretty important.





^^^that's a general rule of thumb guide. Note the wrist pin orientation. For an i4 like ours, rotate that pic 90° clockwise.

Your manual should have a description like that. It may be a little different, but that's what my Weiscos called for. The takeaway is that on those lines where the picture specifies, there's a lot of movement that's not good for the rings to seal. They rock when they're 90° from the wrist pin and they walk slightly when they're parralel with the wrist pin. And obviously, you wouldn't want the gaps on top of each other

That spinning could be a sign of no compression. An old battery that's not fully charged usually isn't that fast at spinning it.
 

Last edited by Conrice; 04-27-2015 at 02:26 PM.
  #168  
Old 04-27-2015, 02:18 PM
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If the gaps are close to each other, it won't build compression.

Low compression offers little resistance during cranking and makes it sound like it's cranking fast, but it will only go as fast as the starter motor will turn it.

Check the compression before you start diving into other systems.
 
  #169  
Old 04-27-2015, 02:49 PM
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Guys, what would I do without you? I'll check compression tomorrow. If I have to remove the engine, at least I won't have to redo the frame work again. Thanks again!
 
  #170  
Old 04-27-2015, 03:02 PM
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Oh, the compression test by the way. I have the tool so I just unscrew the spark plugs one at a time, crank the engine with the starter while having the tool mounted in each spark plug hole at a time and read the values, right? No carbs needed mounted?
 


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