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| | | | Joined: Feb 2006 Posts: 649 'Bolter | | 'Bolter Joined: Feb 2006 Posts: 649 | Just aquired a 54 235 engine, has good oil pressure, but #3 is only running 30 lbs and #1 is @ 120 lbs. The rest all come up with 140 lbs. When I add oil to #'s 1&3 I gain 10 lbs. Maybe from sitting around the valves on those two cylinders need some attention? It does smoke when you rev it up.
Last edited by Yakimabowtie; 02/08/2009 7:13 PM.
| | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | you could have a stuck set of rings as well.
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Apr 2008 Posts: 899 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 899 | Valves seem to be a good choice, pull the valve cover and check movement on bad cylinders with that of good cylinder, your lifters may be hydraulic and have become gummed up or collapsed. If solid lifters, may be adjustment is needed.
Ed
| | | | | Joined: Jan 2008 Posts: 360 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 360 | was told by someone here to check valve stem seals. the o ring type seal was not really good and may be the prob. i have a 60 261 w/ a similar pr0blem and am going to check the valves first. like forty9 said, if it is a powerglide motor w/ the hydraulic lifters, you may have something hanging open as well
"it's only old if you can't find a use for it; otherwise it's cool and i'll use it."
| | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | A leak down test can help determine the problem. | | | | | Joined: Jan 2005 Posts: 364 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 364 | bad valve stem seals will cause smoke upon reving the engine, but will have no effect on compression. Check valve movement first,(easiest). Do you have any history on this motor? Was it sitting a long time before you acquired it? If it sat a long time, could be sticky rings.
Keith
If it were easy they'd have grade schoolers doing it!
| | | | | Joined: Feb 2006 Posts: 649 'Bolter | | 'Bolter Joined: Feb 2006 Posts: 649 | The p/o left it exposed to the weather, starting it every so often, but I'm sure it's been sitting around for sometime. Is there any tricks other than soaking the cylinders with Marvel mystery oil, to free up sticky rings? | | | | | Joined: Jan 2009 Posts: 47 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2009 Posts: 47 | Builder has the right idea, why not do a cylinder leak down test than you can check valves and rings all in one test. Bring that cylinder on tdc add compressed air to that cylinder and listen for air coming out oil dip stick [rings] exhaust pipe [exhaust valve] or out the carb [intake valve]. | | |
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