Re: Best Rear Main Seal Type
[Re: Mopar Mitch]
#2853951
12/01/20 06:58 PM
12/01/20 06:58 PM
|
Joined: Jul 2007
Posts: 1,526 North Carolina
cjskotni
OP
pro stock
|
OP
pro stock
Joined: Jul 2007
Posts: 1,526
North Carolina
|
To clear some technical confusion, the purpose of any rubber seal having helix grooves is to physically throw the oil back in towards the engine... if the seal is installed reverse (with the grooves facing the transmission, it will physically pump oil out of the engine.
It make no difference if the crankshaft has knurls or not... they are there to keep a small amount of oil on the shaft where the seal makes contact.
Rope seals were simple, back in the day, to install and low cost to manufacture... as well as the casting grooves for the seals were not dimensionally held at tight tolerances... where as rubber seals more commonly need a tight fit into their retaining grooves.
I'm a former gasket engineer from a major company... these are common questions being asked. Thanks for the clarification. I had a feeling the rope seal statement needed fact checking. I know this subject is beat to death on here but I have found so much conflicting information, I am beginning to feel like I know absolutely nothing. One last thing - good idea to cut the retainer down .010 or not? I know that will create a bit more "squish" on the seal but will the non-concentricity become an issue?
|
|
|
Re: Best Rear Main Seal Type
[Re: cjskotni]
#2853952
12/01/20 06:59 PM
12/01/20 06:59 PM
|
Joined: May 2005
Posts: 211 ILL
Greentween
enthusiast
|
enthusiast
Joined: May 2005
Posts: 211
ILL
|
This post has some good info in it: https://board.moparts.org/ubbthread...r-main-seal-replacement.html#Post2686329You mentioned you had both OEM and Billet retainers to choose from. If you use the billet one, watch that it has proper clearance so it wont hit the cap as in the post above. I had one that would hit.Ordered a different one and it was fine. When I re-did my rear seal, I did not use side seals and instead filled them with RTV. This worked out for my situation - no leaks. I was doing the job with the engine in the car and with trans attached. I mention this because if the engine is on a stand and your doing it there, I think you can see if the side seals are sliding in correctly and bottoming out. Plus you can then seal the sides again from outside because trans is not there. But while engine is in the car, you loose that ability.
|
|
|
Re: Best Rear Main Seal Type
[Re: cjskotni]
#2854414
12/02/20 03:41 PM
12/02/20 03:41 PM
|
Joined: Jan 2010
Posts: 1,443 NW Chicago suburban area
Mopar Mitch
pro stock
|
pro stock
Joined: Jan 2010
Posts: 1,443
NW Chicago suburban area
|
CJ -- DO NOT cut the retainer.. it will cause excessive pressure against the seal halves and premature wear.
Regarding the side seals, IF you only inject RTV silicone into those side vertical grooves, you need to add some kind of small wet (watered) felt strip into the side grooves.. because RTV .. with that type of thickness.. must have humidity to fully cure.
Otherwise, using the fiber strips often found in seal kits simply requires the strips to be pre-soaked in mineral spirits so that it will properly swell into the side groove.
Pre-molded rubber side strips may not fill the variable side seal gaps... the gaps vary per various production builds.
Mopar Mitch
"Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers!
Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!
|
|
|
Re: Best Rear Main Seal Type
[Re: cjskotni]
#2855653
12/05/20 12:11 PM
12/05/20 12:11 PM
|
Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
master
|
master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
|
Please confirm this is the correct orientation for the crank seal and side seals. That looks right. Getting those side seals all the way down is the hard part. I leave the side seals longer than the cap and work the cap up-and-down so they sit all the way down in the block. Also use a smear (not much) rtv between block and retainer ends. Make sure crank/seal have lube so the seal does not tear on startup. That Summit windage tray looks a bit different than the Jegs version? The Jegs version has slips on the side, and that Summit version looks like it has holes? I used the Jegs version of the windage tray on my 4.25" stroke 440 using an old Mopar Performance Street Hemi oil pan (and the viton rear seal like in the photo), and it sealed great! Really happy with the results. no drips at all. On the other hand, the 4.15" stroke low deck stroker was built with the standard rubber rear seal, and sandwitched factory type windage tray, and it is leaking pretty bad, but the milodon oil pan has taken some damage too. Fixing that oil leak is just another project to get done. I already bought a replacement oil pan, and the Jegs molded windage tray.
|
|
|
Re: Best Rear Main Seal Type
[Re: 451Mopar]
#2855926
12/06/20 09:58 AM
12/06/20 09:58 AM
|
Joined: Jul 2007
Posts: 1,526 North Carolina
cjskotni
OP
pro stock
|
OP
pro stock
Joined: Jul 2007
Posts: 1,526
North Carolina
|
I used the Jegs version of the windage tray on my 4.25" stroke 440 using an old Mopar Performance Street Hemi oil pan (and the viton rear seal like in the photo), and it sealed great! Really happy with the results. no drips at all.
Thanks for the feedback Did you use any RTV or any other type of sealant on the tray/pan? I am picturing a dab of RTV on the joints between the block and retainer/timing cover? Anything else or just install "virgin"?
|
|
|
Re: Best Rear Main Seal Type
[Re: cjskotni]
#2856357
12/07/20 01:24 AM
12/07/20 01:24 AM
|
Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
master
|
master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
|
on the molded windage tray sealing, the seal material will stick to RTV, If you are going to run the engine on a break-in stand or dyno, I would try installing the tray/gasket dry and then check for leaks. Tray and crankshaft seals. You can RTV the gasket and depending on the oil pan rail, you might have to, it just makes the tray gasket material like a one-time use. Once you use RTV with the tray, you will have to use rtv everytime you have the tray and oil pan apart. Not really an issue if the crank seals (front and rear main) and you don't plan to take the engine apart again for a long time.
It is a good question. I had a 505" stroker that a friend and I build with his kid. Somehow, a piston was installed without the compression rings. We had put some rtv at the timing chain cover and rear main seal retainer, so that is when I noticed how the rtv bonds with the trays gasket bead material, when going back into the engine. I need to keep reminding myself to not get distracted when assembling engines, and double check what other people are doing if they are helping. FWIW, I was filing the rings at the time, not installing the pistons.
|
|
|
|
|