Rear Main Seal leak

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Look at your crank right behind your flywheel or flex plate, and tell me how you can adapt a Chubby or any other one piece seal?
Fast fish sells these.

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And they may be a great seal. But your picture proves my point. It is not a one pirrce rear main like a Chevy or most late models use now days.
 
And they may be a great seal. But your picture proves my point. It is not a one pirrce rear main like a Chevy or most late models use now days.
It's a one piece that has to be split. You install it with the seam at the 12 o'clock position. If these were available when I built my 440 I'd have tried one.
 
still has a flange on it way bigger than the circle of a mainseal ------------
Took it all apart, cleaned everything thoroughly, inspected for any flaws and installed a stock rubber type main seal but this time I staggered it I applied a thin layer of ultra gray silicone to the seams of the main seal housing along with a sealant/adhesive that locktite sells to the main seal ends. I let it sit overnight and fired it up today. No rear main seal leak thank goodness.
 
Last week I saw that i have a leak also with the rear main seal. Has anyone tried the trick that 440 source recommends with milling off 0.010" off the bottom of the seal cap?
 
I just rub it on a flat table with some emery paper on it. I have also filed a bit off of it. U can see where the file is removing aluminum. Just make it flat/level. Kim
 
I just rub it on a flat table with some emery paper on it. I have also filed a bit off of it. U can see where the file is removing aluminum. Just make it flat/level. Kim
A few years ago I built a 440 with a Indy rear main seal housing. Couldn't get the side seals to go in correctly with it. Dan Dvorak told me to get rid of the after market housing and use a stock housing.
 
A few years ago I built a 440 with a Indy rear main seal housing. Couldn't get the side seals to go in correctly with it. Dan Dvorak told me to get rid of the after market housing and use a stock housing.
I had the same results with a aftermarket rear main seal cap years ago. Thou i don’t recall what brand it was.
 
A few years ago I built a 440 with a Indy rear main seal housing. Couldn't get the side seals to go in correctly with it. Dan Dvorak told me to get rid of the after market housing and use a stock housing.
By the way i first met Dan Dvorak in the early 70’s. We became pretty good friends over the years. He ported iron heads out to MW port size years before Mopar could spell aluminum head. We are both diabetics and used Bi-Pap machines to sleep. Unfortunately he didn’t take his diabetes seriously and he paid the price.
 
By the way i first met Dan Dvorak in the early 70’s. We became pretty good friends over the years. He ported iron heads out to MW port size years before Mopar could spell aluminum head. We are both diabetics and used Bi-Pap machines to sleep. Unfortunately he didn’t take his diabetes seriously and he paid the price.
Losing a leg is pretty bad but I don't think it slowed him down too much.
 
From what i understand he gets around good and works hard. My wife and i used to hang out with Dan and his wife at Garlits Mopar show every year back when he would attend. He ate terrible and didn’t take the diabetes and sleep apnea serious. Before the divorce. I heard she cleaned him out.
 
From what i understand he gets around good and works hard. My wife and i used to hang out with Dan and his wife at Garlits Mopar show every year back when he would attend. He ate terrible and didn’t take the diabetes and sleep apnea serious. Before the divorce. I heard she cleaned him out.
I take a metformin pill in the morning and in the evening. I don't eat exactly how I should but I definitely lay off of the sweets. Carbs is what I have a hard time with because I absolutely love potatoes..
 
The re-installed seal started leaking the day after I put it in. Not a bad leak just a little drip. So I dropped the steering linkage..the oil pan..windage tray and #5 main cap again. I ordered a "anti leak" seal from Dan Dvorak and installed it except this time I sanded .006 off of the main seal bridge. Fired it up and have ran it several times. No leaking. I believe this time I got it sealed up. I believe what happened is that when I had the machine work done I had the mains align honed. When I went to install the timing chain it fit loose so I had to get a -5 chain to get the proper fitment. I believe throwing the crank location off slightly caused the bottom part of the seal not to fit as snug as it should. Taking off that .006 from the main bridge snugged up the bottom half of the seal.
 
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The re-installed seal started leaking the day after I put it in. Not a bad leak just a little drip. So I dropped the steering linkage..the oil pan..windage tray and #5 main cap again. I ordered a "anti leak" seal from Dan Dvorak and installed it except this time I sanded .006 off of the main seal bridge. Fired it up and have ran it several times. No leaking. I believe this time I got it sealed up. I believe what happened is that when I had the machine work done I had the mains align honed. When I went to install the timing chain it fit loose so I had to get a -5 chain to get the proper fitment. I believe throwing the crank location off slightly caused the bottom part of the seal not to fit as snug as it should. Taking off that .006 from the main bridge snugged up the bottom half of the seal.

where did you buy the seal from Dan? does he have a site to order from?
 
I've been lucky not to have a rear main seal leak after assembly, but to date, I have never staggered the seals. I do always put a small dab of RTV on the ends though.
 
I've been lucky not to have a rear main seal leak after assembly, but to date, I have never staggered the seals. I do always put a small dab of RTV on the ends though.
My problem was having the main caps align honed then having to run a -5 chain. Sanding .006 from the main seal bridge fixed the problem.
 
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