leaky rear main seal help

i built a stroker 400, 440 crnk kb pist etc. balanced polished etc. the rear main leaked a 5 in puddle ev time i parked. ruined a clutch.rubr seal paper sides soked in min sp etc. orange rtv.still leaks. tore dn twice. perfect bearings,end play etc.rubber seal face in,tons of goop, sealed inside, no cracks. sealed engine. double pcv's, still drips 1 drip every 2 sec. exacty 5 qts,windage tray,stok pan,level surf.65lb press.idle, 80 at 2krpm. i cant take it to the trak.it needs a diaper. can anyone help? thanks mark  

The same thing happened to a friend of mine's 440.... he changed the rear seal with a different
brand and that fixed it, his leaked like someone was pouring the darn oil out.... thats all I can think
of, and in his case it worked....  
1959 Dodge Custom Royal Lancer. New Paint, Interior Chrome, 383 Engine, dual exhaust with flowmaster 40's and alot more

If you are certain the seal is installed correctly then I would suggest the following.
Engine oil stop leak. This swells the engine seals.
I too had a rear main issue especially when I used synthetic fluids.
To correct I installed 6 litres of 20w50 valvoline racing oil none synthetic, then I installed the stop leak. 150 miles later not a drop coming out of the rear main.
Several companies make this product under different names, see your local parts supplier for the best product.
Doc  

when the 440 mains got ground to fit the 400 block what was done to the crank rear seal area? double pcv ? u want a positive crankcase vent valve in one valve cover and a breather in the other cover. soak the side seals in oil.  

marco; the crank was cut to stock specs for a 400. i can see the knurl on the seal surface area. i tee'd my pcv tube and put pcvs in both covers.i have a vacuum in the block at idle. i adj my idle to suite.its temporary to try to stop the leak.i wont get on it with the blk sealed,something would pop. mark.  

"sealed engine. double pcv's,"     wait.. this is wrong... there has to be ventilation into the crank case..

double PCV's with no breather... will create so much vacuum in the crankcase that it will pull the seals out of place.. it may also pull the gaskets out of place..

but the worst part... when you are accelerating.. there will be more blowby gasses that get past the rings than the pcv's can handle...  the crank case can build a lot of pressure really quickly..   enough to blow out the rear main seal...  enough to blow out several other gaskets...

the idea of the PCV system is to burn the fuel vapors that get past the rings and into the crank case...

the breather usually has a filter on it.. so it traps dirt... as 90 percent of the time.. the air is flowing into the breather..

during those 10 percent of the time... where you are pushing the loud pedal..  the intake manifold vacuum drops.. the pcv closes off most of its flow and the excess is pushed out the breather ... usually back into the air filter can... where it gets pulled into the intake and burned..

i have also experienced. rear main seals installed backwards...  one got installed backwards in an engine rebuilding shop i worked at .. by a guy who worked there 30 years...  no problem.. send it over to the shop that did warrantee work...  with 5 quarts of oil a filter and another rear main seal..   they changed it.. and it still leaked...  i told them to pull the pan..  and call me... so i could be there when they pulled the rear main cap..   when they did .. and handed it to me.. the new seal was in backwards...  they said.. they thought it went that way.. that was the way it came out..   AAHHRRRR!!!!  

wayne, you are a 100% correct on the pcv issue. this was to try to stop the leak at idle for curiosity sake. normal blowby will pop something. the ref. was to say that in spite of it sucking air in around the seal it was still dripping. the seal def. faces forward.its a moparts seal.would you try a shim behind the seal? mark  

shim behind the seal...  thats an idea....

http://www.moparmusclemagazine.com/techarticles/mopp_0608_rebuilding_mopar_440_engine/photo_09.html

what brand rear main seals are you using????   fel pro , victor,  rock,   ROL,  

thats a stroker crank.... talk to the crank shop who did the work...  

do you have the box the seal came in...   how about a part number????

is there any chance that it is leaking out some ware else..

is the seal retainer cracked...

is it a reverse pitch seal??? for a reverse rotation crank????

did they machine the seal surface on the crank??????/


here is something interesting..

http://www.440source.com/rearsealcaps.htm

this would work better than a shim...

http://www.dvorakmachine.com/rearmainseal.shtml

http://www.hemmings.com/mus/stories/2009/03/01/hmn_tips2.html       this one may only open one time.. without dumping the cookies from your preferences...

http://www.popularhotrodding.com/enginemasters/articles/hardcore/0408em_big_block_mopar_engine/photo_12.html

http://www.moparmagazine.com/2008/jul-aug/high-performance_oiling_systems.html  

is it a reverse rotation marine crank with the grooves on the crank in the seal area going in the "wrong" direction. some makes do this. if this is what U are trying to use oil will be pumped out.  

turning the crank in the direction it runs, the lines start at the end and slant back as they come toward the front. the crank came from a wrecked 1 ton mini dump. i may have to put a scavenging tube on my fly cover to my exaust system. but that wont keep the oil off my clutch #%$&^%@!. maybe i will connect my pcv to the flywheel cover and suck it into the intake.*%^&#$%! i have used an economy seal from advance auto, a paw seal and a jegs felpro. they all drip.maybe i can machine a mini oil slinger to fit between the main and seal. i dont know. im just being silly out of frustration.i think i might try a 7 qt pan and run 6 qts in it.  

DOES ANYONE KNOW HOW TO TALK TO MOP.MUS. EDITOR? I AM GOING TO BUILD A BACKYARD HOTROD, AND WOULD LIKE TO KNOW IF I VIDEO IT, START TO FINNISH, WOULD HE BE INTERESTED? MARK.  

Ok... lets fix this right...

got an air compressor..    a leaf blower that you can totally clean..????/ is the transmission out????  is the motor on a stand????

with an air compressor...    get a pressure regulator..    or just run the compressor for a few seconds to a minute you really don't want over 3 PSI...     block the breather...    pressurize the motor crank case.... have someone looking at the back of the motor and spray it with bubble soap from the 99 cent store or where ever kids stuff is sold..

you might pull the distributer... pull the distributer drive... insert a oil pump priming tool and spin the oil pump to pressurize the oil system.. see if you have a galley plug.. that somebody drilled and it got installed in the wrong position.. on the outside of the block... perhaps a loose plug that was installed into debris..     a tiny crack???

 same process with a leaf blower...  but clean it totally first...   no grass clippings...  new toilet brush through the duct work..  

duct tape it to a valve cover breather...    spin it up.. use some more of the bubble soap..

are you offsetting the rear main seal like people do on other brands..


i wonder if you could pull the seal cap... pull the side seals out..  lay some kind of strong flexible strip in there...   put the cap back on .. just for this trial...   and pull the strip  out.. see if there is some resistance...

was the block line bored????   is it possible that the block crank bore was moved enough that one side of the seal gets crushed.. and the other side just does not touch hard enough..    so... can you measure the depth of the groove with the crank out???     when the block is line bored.. it does move up in the motor....

is the rear seal housing bore lined up with the seal cap is installed without a crank???    like putting a main cap on backwards...  it bolts on.. but the bore does not line up at the parting line..


when you put the crank on the indicator blocks... does the seal surface indicate true???


how much crank thrust do you have..

is the cam plug leaking and fooling you into thinking it is the crank rear main seal..    did the guy at the engine builder dig a groove in the cam bore and the cam plug housing with a big screw driver when he drove out the rear cam bearing and cam plug.

and the last one.. i just remembered..  is the oil pressure gauge line leaking????    that got me one time a long time ago..  but is was on a mid 60 gm truck..

and...  we are talking about a rubber seal...  right.. not a rope seal.. i know we are talking about a rubber seal.. but i do have to ask..  

wow, a lot of food for thought.the motor is in the car and runnin.i got as close as i dared with it running to see if it was coming from above the crank.the flywheel was buzzin my forehead.you are right on the cam cap thought.its been constant thrue 3 rear main seal changes.i believe i will use your thought and add oil to the crankcase above the top of the crank, add some psi and look for drip.the prime my oil pump for a few minutes to check cam cap.the pan bolts dont align on a backwards retainer.when i pulled the mtr last i left in the oil.i hung it by front.it leaked on the retainer sides.any good axpansion sealer out there? thanks, mark  

Leaked on the retainer side? Drain the oil and use silicone. Let it sit over night before you put any oil or pressure to it.
Good Luck Doc  

silicone....  yes...

brake cleaner to clean the area of oil and grease... and GREY ULTRA silicone on the areas you want sealed...

the UTLRA GREY cures harder than normal , clear, blue, black, red....  try it... there is a reason it costs more than the others...

i have also seen an ultra black.. but i have not gotten a chance to try any...