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Compression specs for Vanguard 16HP?

Discussion in 'Mechanic and Repair' started by martin.jim, Aug 17, 2010.

  1. martin.jim

    martin.jim LawnSite Member
    Posts: 5

    Can anyone tell me where I can go to learn what the compression values should be in a B&S Vanguard 16HP engine? Thanks!
     
  2. fixer67

    fixer67 LawnSite Silver Member
    Posts: 2,104

    Try this link. It did not incode right so you will have to copy and paste it.

    http://engines.myfaqcenter.com/Answer.aspx?p_faqid=1864&body_0$tbKeyword=compression%20&selectCats=Troubleshooting%20-%20Repairs
     
  3. laman

    laman LawnSite Senior Member
    Posts: 335

    I checked one that I had years ago. It had 150 lbs, don't know if that is good or bad but it ran strong..
     
  4. martin.jim

    martin.jim LawnSite Member
    Posts: 5

    Thanks for the replies. I'll check that site. I pulled readings from my machine the other day and one cylinder read about 140 and the other about 120. It's been a great engine for a while, but recently started throwing lots of black smoke and has lost top-end power. I'm hoping its a head gasket and nothing worse.
     
  5. dutch1

    dutch1 LawnSite Silver Member
    from Jayhawk
    Posts: 2,231

    If the engine is throwing black smoke, I'd suspect an over fueling problem. Have you noticed an increased fuel usage or an oil level that is higher than normal? If either one is occuring I'd suspect a carb problem--faulty (or debris in) needle/seat, float problem, etc. What are the engine numbers?

    With compression readings, as they are, would not appear to be a problem. The difference in compression raises a little suspicion but it does occur. Have you adjusted the valves?

    Just a couple of thoughts.

    Engine numbers?
     
  6. laman

    laman LawnSite Senior Member
    Posts: 335

    Have you changed the air filter. I had a vanguard and some kind of way the filter got wet. It dried out and it would miss a little and black smoke. I cleaned the carb changed plugs and hunted trying to find it. I had gave up until one day I had it running and pulled the air filter off. The miss and smoke stopped. Put new filter no more problems. Just something for you to check...
     
  7. martin.jim

    martin.jim LawnSite Member
    Posts: 5

    the engine number is: 303776 1088-A1
     
  8. martin.jim

    martin.jim LawnSite Member
    Posts: 5

    I did clean the air filter (it was loaded up) and put new spark plugs in the day it really was acting up - no change. However, the black smoke was bothering me because I was expecting it to be white/blue for a blown head gasket. I pulled off the air filter assembly and found the carb was caked in grime. Used carb & choke cleaner and sprayed/cleaned it all up. Runs much better, but still not getting top-end power like I expect it should. I ordered a new air filter and one other post prompted me to consider adding Seafoam to treat the fuel. I'll fiddle with it tomorrow to see if that all helps. I'm encouraged that maybe the head is not the issue and the carb is. I'm hopeful that will get things worked out enough to get back through the season. I do this part time and run old equipment with my son and we've basically been fortunate to have hot/dry weather to keep work slow while we repair. Thanks for all your help guys!
     
  9. laman

    laman LawnSite Senior Member
    Posts: 335

    I am not talking about cleaning the foam. I am talking about the paper filter. Mine look good but it wasn't.
     
  10. martin.jim

    martin.jim LawnSite Member
    Posts: 5

    I understand...Seafoam is a fuel additive. I did order a new filter and pre-filter and will install them this week. I hope to have the same result you did. Thanks.
     

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