Hello everyone and happy upcoming 4th of July weekend
!! It has been quite some time since my last posted update and for good reason. I had no idea what a pain in the a** properly repairing a rear main seal leak on a 440 could be! I have had the motor out twice since the initial build. The first was to replace the rear main seal and install another freshly built motor minus the casting flash infested block I had used during build of the first motor. Thankfully, Dad had another 440 block sitting in the shop free of coolant flow robbing casting flash in the cooling passages. Upon inspection with a bore scope, I discovered no less than approximately 80% of the cooling passages were blocked with rusted factory casting flash. The replacement block was in much better shape so all machining was completed to build the replacement short block and I installed a new two piece rear main and all was right with the world. Or so I thought! Major rear main seal leak! Here we go again! I trailered the car back up to my Dad's shop and removed everything again, disassembled, and replaced with a one piece rear main seal supplied by Fastfishautoparts.com. Bingo!!! Dry as a bone! That one piece seal of theirs works fantastic! Coupled with a high quality billet aluminum main seal block and following their well thought out directions, I have successfully eliminated the rear main seal leak on my 440!
I researched everything I could find on properly installing the rear main seal and discovered that test fitting and measuring the alignment of the main seal retainer channel to that in the engine block to be a must as well. Also, proper squaring of the retainer in relation to each side of the block by using a pair of feeler gauges during mock up to be of importance. By using the feeler gauges and taking up all of the slop while installing the seal retainer into the block, I eliminated all of the twist of the retainer during installation of the retainer which I believe was the cause of twisting the lower half of the previously installed two piece rear main seal and causing the leak! I purchased my billet seal retainer from 440 source as Fastfish was out of stock and found the 440 piece to be defective! The bolt holes were not concentric to the bolts and upon test fitting, their bolt flange contacted the edge of the bolt hole in the retainer and shifted the retainer out of position. Fortunately, Dad had an extra one on hand from Indy and it was flawless.
I highly recommend the seal from Fastfish. Yes, it is pricey but their one piece design along with proper installation procedures provided a perfect repair and not a single drop of oil leaked after 200 miles of driving and several heat cycles in our Arizona 110 degree weather.
The 850 Holley I had installed had issues as well. It was went into Competition Carburation to have it checked out and the thing was only flowing 725 CFM! Below is a list of the work performed and the results. This improved throttle response significantly!
Flowed 872 CFM ( Air Horn Modified But Air Cleaner Stud Intact)
Jetting Pri. #78 Sec #88
Primary has #4.5 Power Valve (Took Out Blocked Valve)
Both Primary and Secondary Metering Blocks are HP Now
High Speed Transition and Intermediate circuitry in metering blocks re-worked
Inlet Neddle and Seat Size .120
Re- Built Throttle Shafts and Accelerator Pump Linkage
Tested on Engine Run Stand With Big Block Chevy…..Responded Very Well