Red's Headers
Model A-B
Go Fast Gears
Stromberg 97
Demon 98
Coming Soon
Customer's Cars
Engine Talk
About Us
Contact Us
Red's Engine Talk
Previous PageNext Page Contents Page
Oil Leaks & Seals

Nov/Dec 2002

Seals are used to keep fluids where they are needed, and sometimes to keep contaminants, such as dirt, out. Seals are used between parts that have relative motion.  If there is not normally relative motion, then it is a gasket of some sort.  Sometimes the same or very similar material can be used as either a gasket or a seal in our old Fords.

Seal technology has advanced a bit since 1932. Fluid leaks that were common then are not easily tolerated now.  Todays lubricants are far superior to those available in the 1930's, and consequently they leak more than than older lubricants, especially at seals.

How can we keep oil in the crankcase where it belongs?   We can minimize leaks with proper installation techniques.

The rope seals, the front seal being the same part number as the Model A, do a fair job if installed correctly. Once there were made of asbestos with a binder, and sometimes a graphite fiber or rubber cord or core. Most 'rope' seals of current manufacture are acrylic and fiberglass yarns with a rubber binder. They feel limp compared to the older asbestos fiber seals.

There are a couple of full circle lip seals being marketed for the front of  flathead V8s. They install with the pan and the front cover off.  You slide the seal onto the crankshaft seal surface, or the crankshaft front pulley seal surface, with light unfilled grease or heavy engine oil as a lubricant on the lip and seal surface.  The primary lip must be pointed toward the inside of the crankcase. Then, install the pan and front cover with the appropriate gaskets. 

The pan rail gaskets will need to be trimmed to clear the new full circle lip seal.

At the rear of the crankshaft, the rope is still the best that we have, as far as I know.  The best method I have found for installing rope seals is as follows:

Soak the seal pieces in engine oil for 1/2 to four hours.

Before fitting the seal pieces into their cavities,  do a dry fit on the pan, front cover, and/or rear main cap and upper seal retainer. Remove any burrs at the parting lines. Check for proper cam timing, and verify that the cam bolt lock plate tabs are securing the cam bolts properly.  Check the security and safetying of the oil pump. (You did prime it with clean oil, right?)

Check to be sure that the oil pump pickup screen is not against the bottom of the pan; it should be within 1/2" to 5/8" from the bottom. Check the pan rails for flatness.  Do any "body and fender" work required to make it all fit right.  Check the pan side gaskets to make sure that they are the correct ones and haven't shrunk in storage.  If they have, soak them in warm water to expand them. 

When you are satisfied that it will all fit together correctly, then install the oil soaked seal pieces.  Hold the retainer(s) securely so that you can put some force into forming the seal into its cavity.

Center the seal and push the center into the cavity. I then use a large fluted screwdriver handle and turn it in the same direction that you are pressing and "iron" the seal into place. If it comes out uneven, pull it out, shift its position a bit, and do it again until it is right.

(Illustration One)

Almost all of the flathead rope seals are sold cut to length.  After soaking in engine oil and being ironed into place, they will be proud +/- 3/16" on each end. They should not be trimmed, as they will compress properly with the design load on the pulley or the crankshaft seal. 

Oil will squeeze out -- don't worry about that until you get the seals correctly in their cavities. 

Place the pan side gakets so that all the holes line up. I use a thin coat of silicone sealant on each side of each gasket.  Put unfilled grease on the seal surfaces and bolt it all together.  After oil quits squeezing out of the seals, you can clean it up and go the next item(s) on your list.

If you have a crankshaft that just can't hold any seal, check the seal surfaces for run out and finish.  The runout should be less than .001" and the surface should be smooth, with no mechanical damage.

On 32-48 assemblies, if you have trouble with the gasket that goes between the rear cap and the oil pan you can soak it in warm water, then dry it in a #303, or soup can. See the illustration for the bends you need to put in the top of the can.  If the gasket is dried in this curvature, it will want to stay in place instead of popping out each time you let go of it to reach for the oil pan.

(Illustration Two)

This column is a virtual repeat of one I wrote over four years ago, but the topic comes up continually. Oil leaks continue to be a problem for many V8-ers.  I hope in recent years some of the leaks have been sealed, and I know many engines have been rebuilt, hopefully with greater success and more oil staying in the crankcase.

Previous PageNext PageContents Page
Engine Parts     Flathead Headers     Engine Talk     French Flathead

Home   Headers   Early Fords   Mufflers   Flathead Ford V8   Model A-B
Go Fast Gears   Flatattack   Y-Blocks   About Us   Links   Engine Talk   Contact Us

These pages are copyright© 1999-2010 by Red's Headers.