ConcoursMustang Forums

Restoring - General discussions that span across many different groups of years and models => Drivetrain => Topic started by: bryancobb on May 16, 2010, 09:52:45 AM

Title: 289 Rear Main Seal
Post by: bryancobb on May 16, 2010, 09:52:45 AM

Can't remember...   can I replace my rear crankshaft seal on my 66 289C, with the engine in the carm if the transmission is out?  I think I'll have to drop the rear of the oil pan a little bit.  If I remember, the top half of the 2 piece seal ???? can be pushed in from the rear.

Title: Re: 289 Rear Main Seal
Post by: mgmradio on May 16, 2010, 07:42:55 PM

you will have to drop the pan and remove the rear main cap to install the new seal.I would recommend installing a new style seal instead of the rope type.

Title: Re: 289 Rear Main Seal
Post by: macdude67 on May 17, 2010, 09:52:28 PM

if it does still have the rope seal you will have to remove the pin that keeps the old style rope in place in the rear main cap. you won't be able to install the new rubber seal with the pin in place.

Title: Re: 289 Rear Main Seal
Post by: ajd350 on May 17, 2010, 11:07:25 PM

A P.O. of my car proved that the seal will 'go in' with the spike still in place. The seal did not survive, however. Instantly destroyed.  Also make sure that that lip on the seal is oriented toward the crankcase (forward) when installed, and a small amount of sealer is applied to the clean mating surfaces of the main cap. Emphasis on small amount.

Title: Re: 289 Rear Main Seal
Post by: TonyH on March 12, 2020, 11:13:12 PM

Trying to replace the rear main seal on a 390 using the procedure in the 1968 shop manual with the engine/trans in the car (pg 8-111).  Have loosened all of the main bearing cap bolts but the crank is not lowering at all.  What am I missing here?  The procedure is listed in Section 2 titled "In Vehicle Adjustments and Repairs" so I'm assuming transmission removal would be listed if required.

Appreciate any assistance...thanks!

v/r
Tony

Title: Re: 289 Rear Main Seal
Post by: RoyceP on March 12, 2020, 11:56:54 PM

You have to loosen all the mains then pry down on the crank to get enough room. It works. No need to remove the transmission.

Quote from: TonyH on March 12, 2020, 11:13:12 PM

Trying to replace the rear main seal on a 390 using the procedure in the 1968 shop manual with the engine/trans in the car (pg 8-111).  Have loosened all of the main bearing cap bolts but the crank is not lowering at all.  What am I missing here?  The procedure is listed in Section 2 titled "In Vehicle Adjustments and Repairs" so I'm assuming transmission removal would be listed if required.

Appreciate any assistance...thanks!

v/r
Tony

Title: Re: 289 Rear Main Seal
Post by: TonyH on March 13, 2020, 02:26:36 AM

Got it swapped.  Hopefully that will take care of a nuisance leak I've had since I've had the car. 

Thanks!

v/r
Tony