Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 04-25-2019, 07:49 AM   #21
Railcarmover
Senior Member
 
Railcarmover's Avatar
 
Join Date: Apr 2017
Location: Sacramento
Posts: 1,005
Default Re: Rear Main Leak Bear with me

The main bearing leak from excessive clearance or crankshaft end play will leak at the back of the bearing cap and follow the contour of the cap to the front.rear main bearing bolts should be sealed with rtv as part of assembly.Wash the area with brake clean and idle the engine,lay under and watch the area,if the oil doesn't track from the flywheel side of the bearing forward to the pan cork it is migrating through the main bearing bolt hole.
Railcarmover is offline   Reply With Quote
Old 04-26-2019, 06:11 PM   #22
Conaway2
Junior Member
 
Conaway2's Avatar
 
Join Date: Apr 2019
Posts: 26
Default Re: Rear Main Leak Bear with me

Spinelli - what do you think is causing the oil to leak down the rear main bolt ?
Railcarmover - dumb question - how do you seal the rear main bolts with rev ?

I installed a rebuilt engine last month - and have a leak at the rear of the engine - symptoms look identical to Spinelli’s pics.

Many thanks
Conaway2 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 04-26-2019, 08:36 PM   #23
Ray in La Mesa
Senior Member
 
Join Date: May 2010
Location: La Mesa Ca
Posts: 765
Default Re: Rear Main Leak Bear with me

On all the main bolts that extend through to the OUTSIDE of the engine (5 of the 6) I seal with ultra black silicon. Only the passenger side center main bolt has both ends inside the sealed sections of the block & doesn't need to be sealed.
Ray in La Mesa is offline   Reply With Quote
Old 04-26-2019, 09:04 PM   #24
Railcarmover
Senior Member
 
Railcarmover's Avatar
 
Join Date: Apr 2017
Location: Sacramento
Posts: 1,005
Default Re: Rear Main Leak Bear with me

As Ray says I use RTV and hard washers on all main bearing bolt nuts except the center inner...I use regular grade 8 nuts with loctite blue too. Engine oil will track up the main bolts.I found Vw aircooled engine case stud hard washers fit the A main bolt perfectly,hard washers give a positive surface for the nut seat,unlike ford grey iron..
Railcarmover is offline   Reply With Quote
Old 04-26-2019, 11:24 PM   #25
saxman657
Junior Member
 
Join Date: Apr 2019
Location: Orange County, CA
Posts: 2
Default Re: Rear Main Leak Bear with me

I'm experiencing the same thing - I feel your frustration. I can see oil coming from the inspection plate next to the oil pan after about 10 min idle -- pulsing like a slow bleeding artery. I have a mechanic friend who will be helping but thoughts towards either a plugged or missing oil return tube, problems with the shims, or possibly a bad Babbit. He said if Babbit is ok he will drill an extra hole in the Babbit to assist with oil return to the pan.

Looking forward to seeing your progress.
saxman657 is offline   Reply With Quote
Old 04-27-2019, 08:04 AM   #26
James Rogers
Senior Member
 
James Rogers's Avatar
 
Join Date: May 2010
Location: Asheville,NC
Posts: 3,097
Default Re: Rear Main Leak Bear with me

You say it is a pressurized oil system, what seal was used in the rear cap and block?
James Rogers is offline   Reply With Quote
Old 05-03-2019, 10:59 AM   #27
spinelll
Senior Member
 
spinelll's Avatar
 
Join Date: May 2010
Location: Northern New Jersey
Posts: 287
Default Re: Rear Main Leak Bear with me

Quote:
Originally Posted by James Rogers View Post
You say it is a pressurized oil system, what seal was used in the rear cap and block?

James


Hard to say. I bought the car about 10 years ago and it was already "pressured."


Leo
spinelll is offline   Reply With Quote
Old 05-03-2019, 11:01 AM   #28
spinelll
Senior Member
 
spinelll's Avatar
 
Join Date: May 2010
Location: Northern New Jersey
Posts: 287
Default Re: Rear Main Leak Bear with me

Quote:
Originally Posted by Railcarmover View Post
The main bearing leak from excessive clearance or crankshaft end play will leak at the back of the bearing cap and follow the contour of the cap to the front.rear main bearing bolts should be sealed with rtv as part of assembly.Wash the area with brake clean and idle the engine,lay under and watch the area,if the oil doesn't track from the flywheel side of the bearing forward to the pan cork it is migrating through the main bearing bolt hole.

I'll try that.
Thanks
spinelll is offline   Reply With Quote
Old 05-03-2019, 09:30 PM   #29
Chuck Sea/Tac
Senior Member
 
Chuck Sea/Tac's Avatar
 
Join Date: May 2010
Location: Between Seattle & Tacoma
Posts: 1,745
Default Re: Rear Main Leak Bear with me

Have you measured the crank thrust by stepping on the clutch and watching if the front pulley(engine) moves foreword? Worn thrust was mentioned, but I didn’t see where it was checked?
Chuck Sea/Tac is offline   Reply With Quote
Old 05-03-2019, 10:04 PM   #30
Kohnke Rebabbitting
Senior Member
 
Join Date: May 2010
Location: 60615,330th Ave.,Clare, Iowa, 50524
Posts: 1,366
Default Re: Rear Main Leak Bear with me

Quote:
Originally Posted by saxman657 View Post
I'm experiencing the same thing - I feel your frustration. I can see oil coming from the inspection plate next to the oil pan after about 10 min idle -- pulsing like a slow bleeding artery. I have a mechanic friend who will be helping but thoughts towards either a plugged or missing oil return tube, problems with the shims, or possibly a bad Babbit. He said if Babbit is ok he will drill an extra hole in the Babbit to assist with oil return to the pan.

Looking forward to seeing your progress.
First thing to do is to see if all the oil passage is open.

If the drain hole in the rear of the cap won't take the oil now, how will drilling another hole in the cap to feed it more oil, really overwhelming the system, help? Also any oil taken away from the rear of the cap, the thrust will suffer.

Thrust clearance should be set at .003, to .003-50, any thing over .006 is pumping oil. If the rear main bolts, and the shims are not sealed, oil is going through. The shaft set for clearance, as every body knows.

Herm.
Kohnke Rebabbitting is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 03:31 PM.