Mains caps install: Specs & Process
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
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From: Woodinville WA
Mains caps install: Specs & Process
I've been trying to gather some good notes on installing my mains caps / new ARP mains bolts, and bearings and eventually the RMS.
Right now I have the new Cleevite bearings installed and am going to reinstall the mains caps and bolts and torque them down to measure the ID to figure out the oil clearances with the crank. I'm not planning on installing the RMS today but I'd love any clarification on tips there.
I've done some homework and I've read the instructions from ARP, but as always, there are differences of opinions.
Mains Install Specs & Process (SBC 350 L82 4 bolt mains, 1979).
If I got anything wrong or skipped anything please let me know.
I'll add RMS install questions / summary later.
Adam
Right now I have the new Cleevite bearings installed and am going to reinstall the mains caps and bolts and torque them down to measure the ID to figure out the oil clearances with the crank. I'm not planning on installing the RMS today but I'd love any clarification on tips there.
I've done some homework and I've read the instructions from ARP, but as always, there are differences of opinions.
Mains Install Specs & Process (SBC 350 L82 4 bolt mains, 1979).
- Cap orientation and order: I have made sure that I don't lose track of which mains cap goes where; the letters are readable while standing at the rear of the engine and looking towards the front of the engine / the arrows (looks like a Christmas tree to me) point to the front of the motor)
- Fun: I validated that I have the strong nodular iron 2482 4 bolt caps and my 2 bolt cap as the front is 3857, 3851, 3867, or 3851 (so hard to make out these old numbers)
- Torque Specs: I need the most help here. I read different specs all over the internet regarding what torque was originally used. Some say 65 ft lbs inner bolts; 70 outer; some say the opposite and some say something completely different. ARP says 70 ft lbs, but I'm not clear on whether the inner and outer bolts should be the same or different.
- Order: Start with the mains towards the center of the block and work out
- Order of bolts (individual mains): Start with one inner bolt, move to the other inner, opposite outer, final outer
- 3 Step Torquing to final spec: 30 ft lbs, 50 ft lbs, 70 ft lbs -if finishing up at 70 ft lbs.
- Apply torque lubricant to threads and washers prior to tightening them down
If I got anything wrong or skipped anything please let me know.
I'll add RMS install questions / summary later.
Adam
Le Mans Master
Joined: Mar 2004
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From: Little Rock AR
Adam,
In case you did not already know - The main bearing bores will need to be resized if you go to use ARP studs/nuts. The original factory stud-bolts act like a bolt and the new stud/nut arrangement has a different clamping load as compared to the original setup so the main bearing bore will need to be trued up before you can assemble the bottom end if you use studs and nuts. I would follow the ARP instructions to the letter.
I am just finished checking clearances on mine this afternoon. The factory outer bolts are short and got torqued to 60 ft-lbs, the longer inner bolts were torqued to 75 Ft-Lbs.
Block is going back to the machine shop for a deck cut, a bath and some cam bearings this week. Need to cut .025" off both sides.
In case you did not already know - The main bearing bores will need to be resized if you go to use ARP studs/nuts. The original factory stud-bolts act like a bolt and the new stud/nut arrangement has a different clamping load as compared to the original setup so the main bearing bore will need to be trued up before you can assemble the bottom end if you use studs and nuts. I would follow the ARP instructions to the letter.
I am just finished checking clearances on mine this afternoon. The factory outer bolts are short and got torqued to 60 ft-lbs, the longer inner bolts were torqued to 75 Ft-Lbs.
Block is going back to the machine shop for a deck cut, a bath and some cam bearings this week. Need to cut .025" off both sides.
Pro
Joined: May 2016
Posts: 708
Likes: 150
From: Minnesota
Need to line-hone with new bolts. Use ARP torque specs, and lube/washers before you torque them down. Using 3 steps as you are thinking works fine. Work from the inside out. If you start at 30-40 lbft it will be a gradual tighten-down anyhow.
Race Director
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Just a couple of thoughts....
JIM
- Since this is a basic 350 rebuild that won't get hammered on or rev'd to the moon...bolts are fine. Heck...I've still got bolts in my 555" with boost and mega RPM's.
- When dropping in crank...leave rear cap just snug and either pry or tap crank back and forth to align the upper and lower halves of rear thrust bearing. Once it's seated, then torque rear main to final numbers and ck crank end play
- I always offset/stagger the rear main seal to move parting line away from cap/block juncture.
- Make sure you install seal in correct direction!
JIM
Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
Adam,
In case you did not already know - The main bearing bores will need to be resized if you go to use ARP studs/nuts. The original factory stud-bolts act like a bolt and the new stud/nut arrangement has a different clamping load as compared to the original setup so the main bearing bore will need to be trued up before you can assemble the bottom end if you use studs and nuts. I would follow the ARP instructions to the letter.
In case you did not already know - The main bearing bores will need to be resized if you go to use ARP studs/nuts. The original factory stud-bolts act like a bolt and the new stud/nut arrangement has a different clamping load as compared to the original setup so the main bearing bore will need to be trued up before you can assemble the bottom end if you use studs and nuts. I would follow the ARP instructions to the letter.
I went with bolts instead of studs to avoid having to get the mains honed specifically. The torque spec for the arp bolts is almost exactly the same as the stock gm bolts, just much stronger.
Adam
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Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
I’m trying to avoid any expensive machining and use the stock L82 bottom end with basically good piston rings and bearings and stronger ARP bolts and just run it until it doesn’t run good any more and then buy a good shortblock. *My long runner intake will make rpm beyond 6,000 pointless so I’m hoping ARP mains bolts will be fine at that rpm. *
-Do you think I’m ok with bolts vs studs given *my rpm peak and goals or is not going with studs still an issue?
Adam
Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
Just a couple of thoughts....
JIM
- Since this is a basic 350 rebuild that won't get hammered on or rev'd to the moon...bolts are fine. Heck...I've still got bolts in my 555" with boost and mega RPM's.
- When dropping in crank...leave rear cap just snug and either pry or tap crank back and forth to align the upper and lower halves of rear thrust bearing. Once it's seated, then torque rear main to final numbers and ck crank end play
- I always offset/stagger the rear main seal to move parting line away from cap/block juncture.
- Make sure you install seal in correct direction!
JIM
I was totally blind to the need to align the thrust bearings; I need to look up how to set the crank end play- I’ve watched a video demo on checking the clearance between the RMS THRUST surface and the crank with a feeler gauge - is this the procedure used for checking end play?
anyone know a good sbc rebuild book that covers this stuff and goes into step by step how to perform major procedures?
Adam
Safety Car
Joined: Apr 2006
Posts: 4,057
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From: BC
One other little thing is to never use any kind of thread locker on the main or rod bolts. If you get even a little bit between the cap and block or rod surfaces it can throw things off and cause premature bearing wear.
Drifting
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
I agree with stingr69, be sure the new clamping load hasn't changed the size or shape of the mains. In my shop I have go no go bars that I turned on the lathe for most blocks to be sure of this. Same thing with rod bolts when going to aftermarket rod bolts it the rods were resized using the factory bolts first.
Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
On an only mildly related note: I sold my original oil pump stud that connects from the rear main cap to the oil pump... -I thought that a new set of mains bolts OR a new oil pump would come with one; they didn't.
I've been reviewing the Grumpy's Garage thread on installing a rear main seal, and he says that it's a very common mistake to use the wrong oil pump stud, so now I'm paranoid.
-What is the RIGHT oil pump stud to use with a stock main cap and a Melling oil pump? (Should the stud be specific to the oil pump or to the block?) I bought the Melling 10553ST (Shark tooth) oil pump.
Adam
I've been reviewing the Grumpy's Garage thread on installing a rear main seal, and he says that it's a very common mistake to use the wrong oil pump stud, so now I'm paranoid.
-What is the RIGHT oil pump stud to use with a stock main cap and a Melling oil pump? (Should the stud be specific to the oil pump or to the block?) I bought the Melling 10553ST (Shark tooth) oil pump.
Adam
Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
I asked Jegs support which stud to use and they initially came back with a high-volume pump-style stud, BUT my understanding, which could be wrong, is that this Melling SharkTooth pump has a standard pump body size and just has SLIGHTLY (10% more) increased oil volume because the internal shark-tooth gears themselves move slightly more oil, so I should use a standard-style oil pump stud...
Any of this make sense to anyone else?
Adam
Any of this make sense to anyone else?
Adam
Thread Starter
Melting Slicks
Joined: Jun 2016
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From: Woodinville WA
I've also never installed a press-in oil pump screen before.
I have a screen from Champ Pans that was specifically made to work with my oil pump and oil pan; it has a tab that goes to a pump bolt head to hold it in place at the right height, but I'll obviously double-check it.
This video from Melling
seems pretty fantastic for how to install a press-in pickup to a pump, but it requires using a $60 oil pump screen installation tool like this:
-$60 for a tool to install an oil pickup screen one time is nuts; ProForm has one for $18...
I'm all ears on how to install these things correctly for $20 or less in tools.
Adam
I have a screen from Champ Pans that was specifically made to work with my oil pump and oil pan; it has a tab that goes to a pump bolt head to hold it in place at the right height, but I'll obviously double-check it.
This video from Melling
-$60 for a tool to install an oil pickup screen one time is nuts; ProForm has one for $18...
I'm all ears on how to install these things correctly for $20 or less in tools.
Adam
Last edited by NewbVetteGuy; Dec 3, 2018 at 01:25 PM.
Le Mans Master
Joined: Mar 2004
Posts: 7,470
Likes: 1,491
From: Little Rock AR
Adam,
I was under the impression that the "shark tooth" pump was a 5 bolt style Big Block oil pump design that is typically used on a small block engine. That mod has been around a long time.
If Adam is replacing the stock bolts with aftermarket bolts, the clamping force is unchanged so the mains should not need any work to use the new bolts.
I was under the impression that the "shark tooth" pump was a 5 bolt style Big Block oil pump design that is typically used on a small block engine. That mod has been around a long time.
If Adam is replacing the stock bolts with aftermarket bolts, the clamping force is unchanged so the mains should not need any work to use the new bolts.
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
Helical, asymetrical gears inside: http://hotrodenginetech.com/melling-...s-at-pri-show/
They stop the oil "pulsing" that occurs with regular gears and keep the oil pressure more steady throughout the pump's rotation; apparently, introduce less spark scatter if using a distributor, too. (I'm not, but I figure slightly better cam sensor timing isn't a bad thing.)
Here's what Melling marketing says about the SharkTooth pumps, anyway: https://www.melling.com/wp-content/u...e-Pump-Web.pdf
"•SIGNIFICANT REDUCTION IN PRESSURE RIPPLE (PULSING)
•REDUCTION IN TORQUE RIPPLE IN THE PUMP DRIVE
•IMPROVED DISTRIBUTOR OPERATION
- REDUCTION IN SPARK SCATTER
•IMPROVED DISTRIBUTOR GEAR AND INTERMEDIATE SHAFT WEAR"
-Thanks for the confirmation on not needing to hone the mains if the torque spec is essentially the same between GM and ARP bolts. I was definitely operating under that assumption but it always makes me feel better when someone else confirms.
Adam
Last edited by NewbVetteGuy; Dec 3, 2018 at 03:51 PM.
Race Director
Joined: Apr 2003
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From: Tampa, Florida
I agree with stingr69, be sure the new clamping load hasn't changed the size or shape of the mains. In my shop I have go no go bars that I turned on the lathe for most blocks to be sure of this. Same thing with rod bolts when going to aftermarket rod bolts it the rods were resized using the factory bolts first.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
I've also never installed a press-in oil pump screen before.
I have a screen from Champ Pans that was specifically made to work with my oil pump and oil pan; it has a tab that goes to a pump bolt head to hold it in place at the right height, but I'll obviously double-check it.
This video from Melling https://youtu.be/KOIhaI3eEog seems pretty fantastic for how to install a press-in pickup to a pump, but it requires using a $60 oil pump screen installation tool like this: https://www.amazon.com/Melling-MCAT-.../dp/B004A69QJG
-$60 for a tool to install an oil pickup screen one time is nuts; ProForm has one for $18...
I'm all ears on how to install these things correctly for $20 or less in tools.
Adam
I have a screen from Champ Pans that was specifically made to work with my oil pump and oil pan; it has a tab that goes to a pump bolt head to hold it in place at the right height, but I'll obviously double-check it.
This video from Melling https://youtu.be/KOIhaI3eEog seems pretty fantastic for how to install a press-in pickup to a pump, but it requires using a $60 oil pump screen installation tool like this: https://www.amazon.com/Melling-MCAT-.../dp/B004A69QJG
-$60 for a tool to install an oil pickup screen one time is nuts; ProForm has one for $18...
I'm all ears on how to install these things correctly for $20 or less in tools.
Adam
Did you choose a drag or road-race pan?
Also, if you have the gaging I inquired of, perhaps you also verify cylinder bores?
Race Director
Joined: Apr 2003
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From: Tampa, Florida
Free. Loosen the press fit so you can do it by hand then tack weld it. Heat the pump/cool the pickup then install. Over the weekend I couldn't get my new timing chain and gears installed. I hung the chain from a wire and heated it up. Put some gloves and got it all together..