My 496 build

16219 Views 89 Replies 26 Participants Last post by blumont, Apr 15, 2010

blumont

Discussion Starter · Dec 25, 2009

2 bolt Mark iv block,squared and decked, bored .060, torque plate honed,line honed, arp studs

Rotating assembly (thanks Mike) internal balanced
Scat forged 4.25 crank
Scat H beam 6.385 rods
SRP forged 18cc dome pistons
Total seal file fit rings

I got the block back from the machinist and have cleaned it up enough for test fitting.
My main bearing clearances measured by the machinist are .0028 on the mains and .003 on the rear main. Rod bearing clearances are .0023
I plasti guaged the mains yesterday and they appear very close to the machinists measurement I have not tried to use plasti guage on the rods yet. I remember I had a heck of a time with the rods when building my 406. Actually i think I gave up trying to do them

I have checked crank end play by starting first with no caps installed, and then measuring after installing each cap. End play is a tick over .007 consistently at each of the front 4 main caps. I actually had to play with a couple caps as the end play was on the lower side of .007.By unbolting the cap and and retorqing I was able to get the end play back to .007. Is this normal?
I installed the rear main cap and my end play was very low (.003) I unbolted and shifted the cap a bit and retorqued. Still a bit too tight. At that point I figured I would leave it for a day and try again. I might have to sand the thrust bearing down some but will try a few more times before I make that decision.

How do the main bearing clearances look? Research says the .0028 on then mains is good, I am not too sure on the rear main at .003.
Are the rods too tight at .0023?

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Tom Mobley

· #2 · Dec 25, 2009

clearances are good.

the thrust, loosen the rear main cap, tighten it down like wrist tight with a 3/8 drive rachet or similar. then take a Large Ford Tool and a piece of wood, hit the crank HARD on the nose driving it back. then go around to the back, do it again. Hit it hard. What your doing is seating the thrust bearing. then re-check the clearance, should be up near what you saw to begin with, near .007. Then torque the cap and re-check. should be good. If not post back here. There's more stuff you can do.

blumont

Discussion Starter · #3 · Dec 25, 2009

Thanks Tom. I did use the hammer on the crank, but I could not get at it from the rear real well. I have to readjust the mounting position on the engine stand. It is covering the crank right now so I could not get a good smack at it
Any other advice on things to check is more than welcome.

After I get the crank end play sorted out I plan on cleaning and assembling the piston/rods. I then will test fit into the bores to make sure of clearances etc. I will also be filing the rings in the next week or so.

I am hoping it will warm up a bit here before too long so I can use the pressure washer to really blow out the oil galleries and block. I have brushed the galleries now with laquer thinner and brake cleaner. It comes out nice and clear now but want to make sure all the crap is gonzo.

I have read about drilling a small hole to oil the cam sprocket. Should I be considering doing this. The cam will be hydraulic roller on a gen vi step nose core so I can use the retainer plate.
Another thing I am not sure of yet. Screening in the lifter valley? I just seems to me that the screens may stop big pieces of crap getting thru but all the small bits will still drop down through the screen.

I should have added Merry Christmas everyone

There was a present under the tree for me that I figured Santa left for me. I figured hmmm, maybe the AFR heads
Nope, just a big package of Fruit of the Looms

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Wolfplace

· #4 · Dec 25, 2009

blumont said:
2 bolt Mark iv block,squared and decked, bored .060, torque plate honed,line honed, arp studs

Rotating assembly (thanks Mike) internal balanced
Scat forged 4.25 crank
Scat H beam 6.385 rods
SRP forged 18cc dome pistons
Total seal file fit rings

I got the block back from the machinist and have cleaned it up enough for test fitting.
My main bearing clearances measured by the machinist are .0028 on the mains and .003 on the rear main. Rod bearing clearances are .0023
I plasti guaged the mains yesterday and they appear very close to the machinists measurement I have not tried to use plasti guage on the rods yet. I remember I had a heck of a time with the rods when building my 406. Actually i think I gave up trying to do them

I have checked crank end play by starting first with no caps installed, and then measuring after installing each cap. End play is a tick over .007 consistently at each of the front 4 main caps. I actually had to play with a couple caps as the end play was on the lower side of .007.By unbolting the cap and and retorqing I was able to get the end play back to .007. Is this normal?
I installed the rear main cap and my end play was very low (.003) I unbolted and shifted the cap a bit and retorqued. Still a bit too tight. At that point I figured I would leave it for a day and try again. I might have to sand the thrust bearing down some but will try a few more times before I make that decision.

How do the main bearing clearances look? Research says the .0028 on then mains is good, I am not too sure on the rear main at .003.
Are the rods too tight at .0023?

=
HI Jerry
You are welcome & thank you for allowing us to help you :beers:
On the thrust, torque the front four & then the rear while driving a screwdriver or some such thing between any of these mains & a counterweight pretty good prying the crank forward & tighten the rear
See what the thrust is
Now try it the opposite way by prying to the rear if you don'e like it
Use whichever gives you the most
The preferred side to sand is the front cap area of the thrust if necessary but......
You want to blue the thing first to be sure if the cap is cocked slightly you take the material off the high side which may be the rear depending on which way the cap is leaning so check before adjusting

.0023 on the rods is ok I have run it on a BB but I prefer a little more for performance use & would most likely put in a half set of X bearings if you are going to RPM this thing
Mains are good including the rear

Merry Christmas :beers:

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blumont

Discussion Starter · #5 · Dec 25, 2009

Wolfplace said:
=
HI Jerry
You are welcome & thank you for allowing us to help you :beers:
On the thrust, torque the front four & then the rear while driving a screwdriver or some such thing between any of these mains & a counterweight pretty good prying the crank forward & tighten the rear
See what the thrust is
Now try it the opposite way by prying to the rear if you don'e like it
Use whichever gives you the most
The preferred side to sand is the front cap area of the thrust if necessary but......
You want to blue the thing first to be sure if the cap is cocked slightly you take the material off the high side which may be the rear depending on which way the cap is leaning so check before adjusting
.0023 on the rods is ok I have run it on a BB but I prefer a little more for performance use & would most likely put in a half set of X bearings if you are going to RPM this thing
Mains are good including the rear

Merry Christmas :beers:

I tried setting the thrust as you suggested The best I can get is .005. When i am measuring the end play I am measuring when the crank is at rest. Other wards I pry 1 way and release, take a reading, then pry the opposite way , release and measure,
Mike, what is blue you referred to? Ohh, maybe mark the thrust with something and then move the crank for and aft. Makes sense to see where it is hitting if not even.

jbird

· #6 · Dec 25, 2009

blumont said:
I tried setting the thrust as you suggested The best I can get is .005. When i am measuring the end play I am measuring when the crank is at rest. Other wards I pry 1 way and release, take a reading, then pry the opposite way , release and measure,
Mike, what is blue you referred to? Ohh, maybe mark the thrust with something and then move the crank for and aft. Makes sense to see where it is hitting if not even.

Are you using a feeler gauge? Take your reading while you are prying one way or the other, before you release tension.

Or use a dial indicator on the end of the crank, pry one direction, zero the indicator. Then pry the opposite direction and read the indicator.

blumont

Discussion Starter · #7 · Dec 25, 2009

jbird said:
Are you using a feeler gauge? Take your reading while you are prying one way or the other, before you release tension.

Or use a dial indicator on the end of the crank, pry one direction, zero the indicator. Then pry the opposite direction and read the indicator.

I am using a dial indicator on the crank nose. Ok, maybe I am doing this wrong then. I am taking the reading after prying 1 direction and then releasing the crank. Hmmm, if that is the case where the end play is measured at maximum while while prying I am good to go. I probably have .008-9 then. I will check that again.

jbird

· #8 · Dec 25, 2009

blumont said:
I am using a dial indicator on the crank nose. Ok, maybe I am doing this wrong then. I am taking the reading after prying 1 direction and then releasing the crank. Hmmm, if that is the case where the end play is measured at maximum while while prying I am good to go. I probably have .008-9 then. I will check that again.

Obviously, if you pry on it really hard you will gain a little. Just pry it snug, zero it, then pry it snug the opposite direction. Or smack it with a hammer/block back and forth. BTW, IMHO it would be fine at .005.

Wolfplace

· #9 · Dec 25, 2009

blumont said:
I tried setting the thrust as you suggested The best I can get is .005. When i am measuring the end play I am measuring when the crank is at rest. Other wards I pry 1 way and release, take a reading, then pry the opposite way , release and measure,
Mike, what is blue you referred to? Ohh, maybe mark the thrust with something and then move the crank for and aft. Makes sense to see where it is hitting if not even.

=
Correct, just something to mark the bearing or crank so you know you are removing the material from the high point if need be
If you are doing as Jay suggested by prying one way, zeroing & then prying the other way that is your thrust
You need to pry gently each direction to be sure you are squeezing all the oil or assm lube out or you are not getting a true reading
And I agree with Jay, .005 is great,,
Run it

blumont

Discussion Starter · #10 · Dec 26, 2009

Wolfplace said:
=
Correct, just something to mark the bearing or crank so you know you are removing the material from the high point if need be
If you are doing as Jay suggested by prying one way, zeroing & then prying the other way that is your thrust
You need to pry gently each direction to be sure you are squeezing all the oil or assm lube out or you are not getting a true reading
And I agree with Jay, .005 is great,,
Run it

ok, I think I understand, but, if I get a consistent reading when I check after torquing each of the front 4 caps and the rear main cap not tight and then after installing the rear cap get less endplay, it must mean the rear cap bearing is not aligned properly with the bearing in the saddle. Right?
Mike, you think I should use a half set of x bearings to get the rod clearance to .0028? If thats what I need, no problem I will pick up a set of bearings. Got the part number lol

I will go out and play some more in the morning. Right now the the turkey has turned me into a couch potato

Wolfplace

· #11 · Dec 26, 2009

blumont said:
ok, I think I understand, but, if I get a consistent reading when I check after torquing each of the front 4 caps and the rear main cap not tight and then after installing the rear cap get less endplay, it must mean the rear cap bearing is not aligned properly with the bearing in the saddle. Right?
Mike, you think I should use a half set of x bearings to get the rod clearance to .0028? If thats what I need, no problem I will pick up a set of bearings. Got the part number lol

I will go out and play some more in the morning. Right now the the turkey has turned me into a couch potato

=
Smacking the crank with a hammer & block will set the cap as will prying on one of the front counterweights with the rear cap just snug or tightening the rear with the crank pulled forward
When the clearance is not the same with the cap installed it could be the bearing but is usually the block was line honed & the cap did not get cut exactly as it was before or it was that way from the factory which also happens
The reason for the bluing is if you needed to "adjust" the clearance you do not want to shoot yourself in the foot by sanding on the wrong or low side of the bearing
But again at .005 you are good

I normally prefer a little more clearance on any BB that is going to see RPM in the 6500 & up range & for sure in the over 7000 range but I have ran them at .0023 with no apparent issues & consider it my minimum so if they are all this or better you should be fine.
If you decide you want to give it more clearance call me & we will swap out a half set of X's for yours

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blumont

Discussion Starter · #12 · Dec 26, 2009

Wolfplace said:
=
Smacking the crank with a hammer & block will set the cap as will prying on one of the front counterweights with the rear cap just snug or tightening the rear with the crank pulled forward
When the clearance is not the same with the cap installed it could be the bearing but is usually the block was line honed & the cap did not get cut exactly as it was before or it was that way from the factory which also happens
The reason for the bluing is if you needed to "adjust" the clearance you do not want to shoot yourself in the foot by sanding on the wrong or low side of the bearing
But again at .005 you are good

I normally prefer a little more clearance on any BB that is going to see RPM in the 6500 & up range & for sure in the over 7000 range but I have ran them at .0023 with no apparent issues & consider it my minimum so if they are all this or better you should be fine.
If you decide you want to give it more clearance call me & we will swap out a half set of X's for yours

I spent a few hours this morning bonding with the big block. I set the thrust with a bfh and drove a screwdriver (drove is a bit extreme term to use) between the counterweight and the block forcing it forward. Torqued the rear main cap. Now very gently prying for and aft I get .006. I think as you say the cap is the problem. If end play is good at .006 gently forcing it back and forth then I will leave it for now.

I tried plasti gauge on a rod. It went exactly as it did when when I assembled my 406. Very hard to do without the crank moving ever so slightly. I will try it again and get some help to hold things steady.

I did manage to file the second rings this morning. Slow and tedious but all are good at .022

Rmchevelle

· #13 · Dec 26, 2009

blumont said:
I did manage to file the second rings this morning. Slow and tedious but all are good at .022

What did you use to file them? I never had much luck using a hand file so I use a hand crank ring filer.

Tom Mobley

· #14 · Dec 26, 2009

>>> I use a hand crank ring filer.

Me too. Works fine, not as fast as the power gizmos. Be careful of the end gap, keep the ends of the ring parallel.

blumont

Discussion Starter · #15 · Dec 26, 2009

I have the hand crank filer.I take my time and try and sneak up on the gap. The ends look pretty darn good; I tagged each individual ring with corresponding cylinder. When I finished I looked at them and had 2 labelled #2 with no #1. lol. :clonk: Test fitted those 2 again and re-tagged although the bores are identical.

Wolfplace

· #16 · Dec 27, 2009

blumont said:
I have the hand crank filer.I take my time and try and sneak up on the gap. The ends look pretty darn good; I tagged each individual ring with corresponding cylinder. When I finished I looked at them and had 2 labelled #2 with no #1. lol. :clonk: Test fitted those 2 again and re-tagged although the bores are identical.

=
When filing just do one end
This way you have a reference so you can keep it square
Deburr real good when you are done

Of course we cheat because I am lazy

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blumont

Discussion Starter · #17 · Dec 27, 2009

Now that is nice setup!
I only filed 1 end and then dressed all edges.

Sinister

· #18 · Dec 27, 2009

I have a 402A8 Lunati cam and lifters, brand new still in the box. Let me know if you are interested. I went with a solid roller. I had the same set up until I went with more compr, new heads, etc...

blumont

Discussion Starter · #19 · Dec 31, 2009

Update

Test fitted everything and took it back apart. I gave the block a soapy bath and cleaned all passages again and again. The thrust bearing issue earlier was still bugging me. This morning when checking end play again I noticed the dial indicator move when I set the cap in the registers. It showed me that it was the rear thrust flange that was hitting early. I took the rear bearings out and used an outside mic. I found a high spot on the bearing. I was able to work the high spot out with some very fine emery paper.
I installed the crank again and measured end play as each cap was torqued. Now end play is consistent with every cap install. Much better!!
Crank is now installed permanently, I hope

Rmchevelle

· #20 · Jan 1, 2010

That's good news, Jerry.

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