Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Replaced B&S Head Gasket & Valve Cover Gasket - Still Smokes - What Next?


NautiDIY's Avatar
Member

Join Date: Oct 2014
Posts: 4
NH

10-23-14, 06:41 AM   #1  
Replaced B&S Head Gasket & Valve Cover Gasket - Still Smokes - What Next?

I just replaced the B&S head gasket & vavle cover on my neighbor's B&S lawn mower motor:
Model: 331877 2371
Type: G1
Code: 10101ZD


  1. The neighbor's lawn tractor was smoking bluish smoke & running badly.
  2. He then replaced the spark plug, air filter, oil filter, fuel filter and changed the oil. However the motor still smoked badly & ran very rough, couldn't get full rpms.
  3. I checked the spark plug & it had a oil on the electrode & threads.
  4. So, I replaced the head gasket that he purchased (P/N 273280S) & incrementally torqued it to 220 lb-in. using the B&S torquing sequence.
  5. I then made the valve cover gasket with the RTV material, running the bead, finger tightening the screws, waiting an hour for it to cure, torquing it to specs, and waiting 24 hrs to cure.
  6. It still smoked.
  7. I checked everything & all looks good(???).
  8. It still smokes & runs very rough & I can feel air puffing out behind/below the valve cover from a hole that looks like it was designed into the casting.
  9. I "think" this reduces pressure to help start the motor, but I'm not sure.
  10. What is going on & what can I do next?

I'd really appreciate your help to solve this problem.
Al

PS After the above, I checked the parts & found that the recommended B&S Head Gasket is P/N 794114 instead of P/N 273280S. From what I can tell the only diference is a tab on the P/N 794114 that connects two gasket holes, whereas the P/N 273280S does not have this tab. I can see no port that is covered by this tab. Does the tab serve a purpose? So, is it OK to use the gasket without this tab?
Thanks for your help!

 
Sponsored Links
NautiDIY's Avatar
Member

Join Date: Oct 2014
Posts: 4
NH

10-23-14, 08:25 AM   #2  
29 views & no responses.
Does this suggest there is no fix for this problem?
Hoping someone can help.

 
Pilot Dane's Avatar
Group Moderator

Join Date: Mar 2003
Posts: 16,676
NC

10-23-14, 09:41 AM   #3  
Most of us have jobs and don't spend our lives staring at the forum 24/7 waiting to give free advice.

 
NautiDIY's Avatar
Member

Join Date: Oct 2014
Posts: 4
NH

10-23-14, 11:54 AM   #4  
So why is there now 70 views? Lots of people "staring"!
I thought the rules of this forum was to not respond with smart-ass answers.

 
NautiDIY's Avatar
Member

Join Date: Oct 2014
Posts: 4
NH

10-23-14, 02:30 PM   #5  
Decided to start over & check the work my neighbor did. Found some interesting things:
  1. The air filter had shipped to him with the foam pre-filiter inside the core of the main filter. He hadn't removed the pre-filter & installed it around the main filter.
  2. He hadn't gapped the plug to 0.030", instead he left it as received at 0.035"

I made those corrections & the tractor started right up. It blew a lot of smoke until the muffler cleared out. Runs fine now!

Oh, he had worn out the battery trying to start the tractor just before I decided to go back to basics. The battery is now being charged with my battery charger.

Lesson learned. Always check to be sure of every step in the process, especialy if done by someone else.

 
Search this Thread