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#51118 10/13/2005 11:38 PM | Joined: May 2005 Posts: 25 New Guy | | New Guy Joined: May 2005 Posts: 25 | Recently completed a rebuild of the 235 (1954) in my 41 truck. Slowly breaking in the new engine-about 300 miles so far.
During a soft drink stop this pm I noticed an oil puddle at rear of engine. Checked oil level-OK-and made it home fine. Late this afternoon, I noticed a larger puddle of engine oil again at rear of block.
Rear main seal? Is there any hope the seal will reseat? Or should I figure on rear seal replacement?
Checked the archives on rear seal replacement. Do these apply to 216's and 235's?
Suggestions appreciated. | | |
#51119 10/14/2005 12:35 AM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | jones, You can hope it will reseat itself..in the mean time buy some shares of Standard Oil, you'll need it. On the flip side, it might be the pan gasket, but they usually leak right off. Procedures for repair or replacement will apply to either 216 or 235 engines. Make sure you know where it is originating before you rip into it, could be the back of the valve cover ....  Stuart. | | |
#51120 10/14/2005 2:03 AM | Joined: Sep 2003 Posts: 1,820 Shop Shark | | Shop Shark Joined: Sep 2003 Posts: 1,820 | ... yes, it could be the back of the valve cover, the lower rear corner of the side cover or it could be the flywheel. That's right ... the flywheel. When rebuilding these engines I have found more than one machine shop pull the dowell pins out of the back flange of the crankshaft - the pins that line up the flywheel when you bolt it onto the crankshaft. Check to be sure they are there. If not the hole they go into goes right through the crankshaft flange into the oil pan cavity. It will pump the oil out into the flywheel cover and it drips on the ground. You would swear it's the rearmain seal! I believe there are two or three of these pins in the crankshaft flange. It only takes one! Hope this helps you out! Joe 
"Truckin' Around .......... Since 1937!" My name is Joe and I am addicted to Classic Country Music. I just can't hep myself.Operators are standing by to take your calls! Now cruising in the Passing Lane | | |
#51121 10/14/2005 2:16 AM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | 6cylinders,
Don't want to rattle the Texan, but are you sure? I am trying to visualize the dowel pins into the crankcase and I can't get them past the rear main or the block... I have only messed with a 235 though. :confused:
Stuart. | | |
#51122 10/14/2005 2:44 AM | Joined: Feb 2004 Posts: 29,787 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,787 | I can confirm that- - - - -the holes for the flywheel attaching bolts and the dowel pin holes go all the way through the crankshaft flange, and are open to oil from the crankcase. One flywheel bolt was left out of my 59 235 during a rebuild, and it oil-soaked the clutch to the point I had to replace it.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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#51123 10/14/2005 2:49 AM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Well I'll be dipped in whatever they have in TN or TX. 6cylinders, I owe you a beer next time you come to CA. :o
Stuart. | | |
#51124 10/14/2005 4:36 AM | Joined: Sep 2003 Posts: 1,820 Shop Shark | | Shop Shark Joined: Sep 2003 Posts: 1,820 | The dowel pins are in the crankshaft flange. The rear main seal goes around the crankshaft itself just on the back side outside of the flange. The bulk of the flange is inside the crankcase of the engine. The bolts and dowell pins stick out of the flange on the backs side of the flange. The holes really do go all the way through into the crankcase. The oil will really come out and it will ruin a clutch in no time. Hotrod Lincoln knows and I had a 261 totaly together and running only to find huge puddles of oil on the garage floor after several test runs. ALL of the dowell pins were out of the flange! How in the world I got the flywheel on in the right position, I couldn't guess except the holes just happen to line up right! I would check this. It's sure not hard to check. Joe
"Truckin' Around .......... Since 1937!" My name is Joe and I am addicted to Classic Country Music. I just can't hep myself.Operators are standing by to take your calls! Now cruising in the Passing Lane | | |
#51125 10/14/2005 12:48 PM | Joined: May 2005 Posts: 25 New Guy | | New Guy Joined: May 2005 Posts: 25 | Thanks to all. Weekend coming up. Will post when I isolate and repair the problem. | | |
#51126 10/15/2005 1:38 AM | Joined: Mar 2004 Posts: 313 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 313 | Jones, I am having the same problem. I have a 1957 235 in my 49 Chevy truck. Hotrod lincoln told me exactly what to do, but I just haven't had the time to tear into it yet. Like your engine, mine only has about 300 miles on it too. It only drips oil if I drive it about 10 miles. If I just drive it around the subdivision, it don't leak. I am curious to know what you find out.
KT
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49 Chevy Truck
1953 3100 with 1957 235, T5 and 12 bolt 373 rear
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#51127 10/15/2005 4:54 AM | Joined: Sep 2003 Posts: 1,820 Shop Shark | | Shop Shark Joined: Sep 2003 Posts: 1,820 | I actually got that wrong! Darn - first time this week! The seal goes around the crank shaft on the INSIDE of the flange - at the rear main. The flange is outside of the engine on the back (of course). All other references to the potential problem remain the same. Joe
"Truckin' Around .......... Since 1937!" My name is Joe and I am addicted to Classic Country Music. I just can't hep myself.Operators are standing by to take your calls! Now cruising in the Passing Lane | | |
#51128 10/17/2005 1:48 PM | Joined: May 2005 Posts: 25 New Guy | | New Guy Joined: May 2005 Posts: 25 | Many thanks for all the suggestions. Saturday morning, trouble light in hand, checked the drip.
Turns out the oil pan plug is doing most of the leaking.
After changing oil and filter, I reinstalled oil plug with a rubber gasket. Fewer drips now, but may have to re-tap oil pan for new plug.
Rather do that than change out rear main seal!!
Jones | | |
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