Rear Main Seal Alternative Interchanges

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                                        Rear Main Rope Seal Alternative

The AERA Technical committee supplies the following information on a rear main rope seal 
alternative. The information provided below was collected over many years. This information is 
feedback from people like you. People tell us these seals have worked fine for them but will 
they work for you? AERA expresses no guarantee that they will work 100% of the time but the 
seals listed below have proven to be the most successful.

During installation, offset or rotate each seal half ? to 3/8 from the main cap parting line. 
Place dab of anaerobic gel on the ends of the seals that will butt together. Lubricate the seal 
lip with straight 50 W oil or a bearing assembly lube as those lubes that will stay in place 
until the engine is started. Seal manufacturers do not recommend white grease alone, because 
they have seen too many failures from dry startups. This is especially true in rebuilt engines 
that sit on the shelf for long periods of time before being put into service. This is why you 
may have seen chunks torn out of the contact face of the seals that have leaked. 
If you have ever seen a Ford 390 or 460 tear the whole lip off the seal, it happened because 
it was dry started and stuck to the crankshaft.
Engine to Be repaired Detroit     Enginetech      FM     ROL      Victor      Actual Application
Buick 231 17200      S-1389      BS-40613     RS-29470     JV-742-V         Jeep 225
Buick 35017043    N/A    BS-40032    RS-29130    JV-618        Ford 460
Buick 45517042    N/A    BS-30135    RS-29050    JV-730        Ford 200
GM 265/28317053    S-0629    BS-13241    RS-29005    JV-728        Chev 250*
Caddy 36517032    S-1196    BS-40245    RS-29040    JV-606        Dodge 318
Ford 31217032    S-1196    BS-40245    RS-29040    JV-606        Dodge 318
Olds 260 307 330 350 40317175    N/A    BS-6141    RS 29310    N/A        Ford 292
Olds 350D 400 425 45517043    N/A    BS-40032    RS-29130    JV-618        Ford 460
Pontiac 30117091    N/A    BS-40048    N/A    JV-616        GMC 637
Pontiac 350/40017043    N/A    BS-40032    RS-29130    JV-618        Ford 460
Pontiac 45517008    N/A    BS-40012    RS-29115    JV-600        Caddy 500
* Install a .090 (2.290 mm) diameter wire in the groove, behind the seal.
It has also been reported that replacing the timing case rope seal with a National seal Part #450446 has proven effective on 455 Buick engines.
On engines which use rope anti-rotation holes in the block and cap, fill them with RTV and let dry over night.