My 427 SOHC Build..... Finally the time has come!

[ScotiaFE]

A small smear of RTV Ultra black on the side seals will give it a bit of lube to slide the seal
all the way down.

[My427stang]

I like the side seals that use nails. 

Easiest way I have found is to assemble without side seals.  Then gently shape each side seal on a sanding block so it will just barely slide in.  Lube it with your favorite RTV and slip it in all slathered up.

After its in, take the nails, but them on the crank side so they push outward and drive them in with a punch that will actually push the seals below the surface and "marshamallow" them out as you drive the nail in.

A another little dollop of RTV on top to get it to pan rail height and life is good

[cobracammer]

I just went down to the local auto parts store and ordered a new rear main seal set (will be in tomorrow afternoon).  I made sure that this set came with the side seals that come with the nails.  I am a little confused though, do the nails help you slide them down?  Are they left in the side seals?  Or are they just a tool that comes with the set?

[cobracammer]

OK Just finished reading some posts on this forum about the technique on installing the rear main seal.  It seems that there are a few tricks.

The seal needs to be installed clocked at about 2 and 8 (So the seams are not exactly where the block and cap meet)

A dab of sealant is placed on the end of each seal half (So they cure together)

Smearing of the sealant on the mating surface seems to be a given.

The side seals seem to have the most variety.  It seems like you always have to trim them a little thinner so they will slide into the grooves....  Also most people use the sealant as a lubricant.  Also looks like the nails are used to push the seals the rest of the way in (and the nails are left in after they are hammered down).  RTV is dabbed on the topsand then trimmed flat with a razor after it hardens.

Ill give it another go tomorrow night after I get the new set.

Also, do you have to whack the crank with a hammer to seat the Thrust bearings?  It seems the Thrust bearings are in the #3 journal, so how does that work???

[ScotiaFE]

Also, do you have to whack the crank with a hammer to seat the Thrust bearings?  It seems the Thrust bearings are in the #3 journal, so how does that work???

The centre main bearing is the thrust bearing. When you put it in it had a skirt or shoulder that wraps around the main cap and block.
It has two purposes.
1. It controls the forward and back motion of the crank when spinning.
2. It provides the load surface when you push the clutch pedal in.

Because the bearing is split the parting lines need to be set. I prefer to use a large screw driver (I have a really big one lol) and pull the crank back
using the crank flange  and push it forward using engine stand to push on. This will true up the two bearing halves and you can also check your crank
end play. Not a big fan of using a BFH to tune up the crank.

[cobracammer]

Awesome!  Thanks.  I will do this all tomorrow and button up the crank for good!  It feel great to get the first step complete!

[jayb]

OK Just finished reading some posts on this forum about the technique on installing the rear main seal.  It seems that there are a few tricks.

The seal needs to be installed clocked at about 2 and 8 (So the seams are not exactly where the block and cap meet)

A dab of sealant is placed on the end of each seal half (So they cure together)

Smearing of the sealant on the mating surface seems to be a given.

The side seals seem to have the most variety.  It seems like you always have to trim them a little thinner so they will slide into the grooves....  Also most people use the sealant as a lubricant.  Also looks like the nails are used to push the seals the rest of the way in (and the nails are left in after they are hammered down).  RTV is dabbed on the topsand then trimmed flat with a razor after it hardens.

Ill give it another go tomorrow night after I get the new set.

Also, do you have to whack the crank with a hammer to seat the Thrust bearings?  It seems the Thrust bearings are in the #3 journal, so how does that work???

I wouldn't clock the main seals as far as 2 and 8; you'll never get the rear main cap on without hurting the seal.  Offset them so that one side of the seal is sticking out of the block about 1/8"-1/4", and match the other one in the cap, and you can still get the cap installed without damaging the seal.

Also, I've never used silicone on the ends of the seals; I read somewhere once that that's a bad idea.  Not sure why, but FWIW I leave the ends of the seals dry.

You really don't need to seat the thrust bearing; after you have the crank in and the bolts torqued, you can pry against one of the counterweights, forward and backwards, to force the crank against both sides of the thrust bearing.  A lot of guys will measure end play in the crank that way.  I would NOT whack the crank with a hammer.

Howie's advice about measuring the bearing clearance is spot on, and I think Ross's idea for the side seals is a really good one.  I always struggle with those things myself; I think I'll try Ross's method next time...

[My427stang]

Same thoughts here

I don't clock a seal, too much chance to crush it and I dont add RTV.  The seal actually crushes a bit, so silicone won't do much even if you did use it, they are designed to crush together slightly.  I will oil the seal very lightly on the sealing lip though just before I drop the crank in.  Also, double check you are putting both halves in the correct direction, make that triple check!  Been a long time, but I have made that mistake....

Last thing I would do is smack a crank, although a forged unit should be fine, a habit like that could have you breaking cast cranks.  Not to mention you cannot control or measure it. 

Better method is to set up your dial indicator without the thrust cap on, check it with the bottom only, if its good or more than required, put the cap on loose, pry the crank forward, torque it and check the thrust clearance. Prying will move it as much as a hammer will and you can watch the clearance on the dial indicator as you go full forward and full back.

One think to look at though, look at the main cap and see how it dumps oil. See the "mouth" or grooved slot on the main cap below?



That slot dumps the oil pressure, the seal only seals against what splashes there not oil pressure.  In only a few cases over the years I have seen windage trays, oil pans, or even just excited RTV application block that slot. Check yours during assembly.  Otherwise, you bolt the pan on and pressurize the seal and it will never hold 50+ psi.  it doesn't happen a lot, but it can happen

[cobracammer]

Also, yet another question.......

I plan on taking it apart (just to be sure) and measuring the bearing oil clearance again on the mains.  I figure I have time (In no rush and want to make 100% sure its done to spec).  The interesting thing is, if I try to turn the crank by one of the counter weights, its very difficult to turn, however, if I turn it by the crank snout with the ratchet, I am able to spin the crank over with 1 finger and barely any pressure.....

Is this normal?

Like I said, I am going to pull it out and measure the clearances all again for piece of mind.

Thanks

[jayb]

How easily the crank spins over will depend on the assembly lube you are using and the bearing clearances.  What I look for mostly is that it turns over smoothly through 360 degrees, with no rough or sticking spots.  You should be able to move the crank pretty easily by pushing on one of the counterweights; if you can't, there may be a problem.  Look for a shiny area on the oil slinger to check for interference with the block at that point. 

One thing you might try is spinning the crank with no caps installed, then install #1 cap and feel how that affects the force required to spin the crank, then remove #1 and install #5 with no seals, and see if it feels the same as when #1 was installed.  If it feels the same, then you probably don't have interference between the oil slinger and the block.  If it is a lot stiffer though, you have a problem there.  When I had that issue it would lock the crank up pretty tight, but maybe they don't all do that...

[cobracammer]

I was noticed something.  When I ordered Main bearings from Summit racing, I ordered a standard set.  When I was installing them, I found it odd that the top shell had a groove for the oil, but the bottom shell (that goes in the cap) was smooth with no channel for the oil.

I went to Jegs website, and it seems like they are supposed to have a channel on both halves of the shell.  Its possible that they sent me the wrong ones.  As I ordered standard, I didn't even check to make sure.  When I get home, I will double check.  This is why I no longer use Summit racing and have since switched to jegs.   Worse comes to worse and they are the incorrect ones, I then need to reorder the standard size again from Jegs.

This would definitely explain why I was getting odd numbers on the clearances as well as the difficulty to spin by hang.  The assembly lube I am using is very viscos.  Its a lube by "red line".

I am going to check the bearings when I get home, but am I correct in thinking they are supposed to be grooved on both halves of the shell?

[Heo]

no the lower Shell is not groved. To give bigger
bearing Surface on the preasure side

[cobracammer]

I see.  I just went back through my orders and see that I got these:

Speed Pro:  Main Bearings, Competition, Standard Size, Super Duty Alloy, 3/4 Groove, Ford, Big Block FE, Set of 5

They are standard size, but 3/4 groove.  I think I went with them because they were "Super Duty".  I feel a little bit better.  I saw that the sealed power standard bearings come "Full groove" so it got me thinking (Dangerous)

 

[Heo]

 Yes wery dangerous More people have ended up on the funnyfarm by thinking
than by any other reason

[cobracammer]

Well, Just to be safe, I went ahead and ordered another set of bearings (Undersized) so I have them on hand when I re-measure.  They are 0.010 undersized.

I also picked up an oil slinger for the Crankshaft nose.  I actually asked Keith Craft about this while I was in my hoarding parts phase, and he said I don't need it.  I figure (even though I will have squirters like Jay's design, it cant hurt to have more oil being flung up onto those chains and gears at speed.

Another item Keith Craft said I didn't need was a windage tray.  I felt like it cant hurt to have one, so for an extra $60.00, I got the one that works with my rear sump Canton Pan and pick up.  My only concern is that this is a stroker motor and at 4.250 stroke, the windage tray may cause interference???  Either way I have it on hand  :0)

I have to say that I love this stuff. Can't wait to get home and get back into the garage!  LOL