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1992 Chevy S10 4.3L V6 2WD

I read about putting SeaFoam in a gas tank instead of the crankcase because it takes away the carbon. I also read that is not necessarily a good thing in older vehicles because it will cause older motors to burn oil.

I put SeaFoam in my gas tank and now my truck blows bluish smoke on startup.

I believe that prior to doing this my motor was already burning oil. I also believe it has a rear main seal leak.

  1. If I chose to get a rebuild kit and rebuild my motor, do you think this will help my oil burning problem even after I removed all of the carbon?
  2. Do I have to rebuild my motor to fix the puffs of bluish smoke that come out of the exhaust pipe everytime I start my truck?
  3. Is a rebuild my only option here?
Zach Mierzejewski
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bchisum_11
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1 Answers1

10

Usually the puffs of blue smoke on startup are actually caused due to leaking valve seals. These can be changed without the need for an engine rebuild. Changing them out also can be done while the engine is in the vehicle.

You could use this YouTube video as a source for directions for changing out the valve seals. The 305 will have the same valve train setup as your 4.3L does, but yours will have two fewer cylinders.

Basically:

  • Remove valve covers
  • Remove the rocker arms (keeping them in order - they need to go back to the same spot)
  • Remove the spark plugs
  • Pressurize the cylinder
  • Using a spring compressor, remove the keepers, then the spring
  • Remove/replace valve seals
  • Replace the spring, retainer, keepers (repeat the previous 4 steps for all valves)
  • Replace rocker arms and adjust
  • Replace valve covers using new gaskets
  • Replace spark plugs
Pᴀᴜʟsᴛᴇʀ2
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