Oil leak bell housing

Gene B.

Junior Member
May be showing my lack of mechanics. Could crack in the transmission or flywheel housing result in a oil leak? It looks like the leak would have to come around the crankshaft bearing or bearing/seal on front side of transmission for it to get into this area. Is there some other opening or orifice opening into this area? I figure you do not want oil getting into the clutch area?
 
I would also like to address this problem by saying, if you park or drive your car up a steep incline it will leak here particularly if it is full or even slightly over full of oil. If it leaks all the time, follow Brent's advice.
 
May be showing my lack of mechanics. Could crack in the transmission or flywheel housing result in a oil leak? It looks like the leak would have to come around the crankshaft bearing or bearing/seal on front side of transmission for it to get into this area. Is there some other opening or orifice opening into this area? I figure you do not want oil getting into the clutch area?

Hey Gene,

'crack in flywheel housing'
The rear of the camshaft protrudes into hole at rear (bearing) of block. There is supposed to be some seal/gasket to prevent oil leak. Cracked flywheel housing may allow the seal to be broken ? If no seal or is broken seal...ergo leaking oil.
 
Search for "Rear Main Leak" and you will likely find your answer.

I would also like to address this problem by saying, if you park or drive your car up a steep incline it will leak here particularly if it is full or even slightly over full of oil. If it leaks all the time, follow Brent's advice.

They are not giving you a snotty answer. there are a whole bunch of things that could cause your problem. Few are easy solutions, many not for the rear to leak.
 
The rear of the Camshaft can leak if the gasket is missing or damaged flywheel housings tend not to crack in the camshaft area
It is most likely the rear main leaking
1 test is remove the flywheel housing dust cover or starter and look at the inside of the flywheel if it has oil then it is the rear main
 
Gene,
Pat's link above to antique engine rebuilding is a good troubleshooting /suggestion guide.

It is normal for there to be a small leak now and then... not sure how big yours is... but by design there is no seal at the rear main, just an oil slinger. Some engines leak a significant amount ( I have watched the trail of some pull into my driveway!)... and others leak very little. This is due to many factors... you will read about them best in the search they described. The cotter key in the bottom of the flywheel housing is by design to keep the hole clear and provide an escape path so there is not any oil buildup. As Brent and others said, search the forum for "Rear Main Oil leak" and you will find many replies as well as The link above.

Read up on it, analyze it... and if necessary recruit another schooled Model A person nearby to guide/help you. The leak you have may be the normal amount so don't fret. Check it out and report back on this thread. Also, remember a small amount of oil spreads out to look like a lot...

Larry Shepard
 
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Thanks for the replies. Flywheel housing has crack about 1-2 inches long from where cam meets housing. Going to take out motor and replace flywheel housing. Appears rear main is not leaking.
Going to go ahead and remove pan to check slug, make sure rear main return pipe is open, and oil pump screen, etc.
Only good thing about pulling motor is checking conditions of clutch. Also going to replace motor mounds with new style. I think these will help cushion the motor better. Rubber on rear mounts harder than a rock.

Question- it would cost about $400 to replace flywheel with later lighter weight wheel. Is this cost worth it?
While I got ya- Truck does not have oil pan panels. Going to add. I believe they will help keep some dirt from swirling around motor and also help keep motor cooler. What is your opinion?
 
The cost of going to a lightened FW assembly is not 400$ If you replace the original clutch and pressure plate with new it will cost about 150$. The flywheel grinding will cost 50$ most places and replacing the starter ring is 25 + shipping for the ring and 25 or 30$ to install it. Now you are at about 200$ for comparable new parts. Figure what a machine shop will charge to cut the flywheel and redrill it, 100$ then it will need to be balanced at 125$ most speed shops. 425$ is what it would cost if you do it yourself or contract it out. The benefit is the balance is much better making the engine smoother and removes some of the whip out of the crank improving the center mains longivity and the lighter flywheel makes your rear main have a much longer life.
 
Gene - are you positive that it is engine oil? It is possible for oil from the transmission to enter the bell housing via the shifter rails where they protrude into that area. Have you recently topped off the transmission? Is the small vent hole on the back side of the shift tower clear?
Is this a leak that has been going on for a while or something that just started?
 
Oil leak for sure. Took to knowledgeable A mechanic. Just purchased truck with understanding it had small (slow) leak. Not small to me. Leak at crack where Cam Shaft fits to back of block. Just looking wonder how some much can come through crack?
Some trans oil dripping from cotter key hole bell housing. Have not checked level, but could be over fill. Is what I call a very slow leak (drip).

Appreciate Dreamworks response concerning light flywheel, but realizing they are in business. Would like to have opinion of others concerning the cost benefit and performance benefit of changing wheel. The price from Dream seems good considering the clutch and pressure plate come with the wheel for $425.
 
Thanks for the replies. Flywheel housing has crack about 1-2 inches long from where cam meets housing. Going to take out motor and replace flywheel housing. Appears rear main is not leaking.
Going to go ahead and remove pan to check slug, make sure rear main return pipe is open, and oil pump screen, etc.
Only good thing about pulling motor is checking conditions of clutch. Also going to replace motor mounds with new style. I think these will help cushion the motor better. Rubber on rear mounts harder than a rock.

Question- it would cost about $400 to replace flywheel with later lighter weight wheel. Is this cost worth it?
While I got ya- Truck does not have oil pan panels. Going to add. I believe they will help keep some dirt from swirling around motor and also help keep motor cooler. What is your opinion?

What are "the new style motor mounts"? If you are talking "float-a-motor" mounts you might search it in the archive. I don't think the jury is in yet but I like the original mounts.

Charlie Stephens
 
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