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Tappet adjuster torque

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malcox Avatar
malcox Malcolm Cox
Napa, California, USA   USA
Until recently, I never bothered to torque the tappet adjuster nuts, just gave em a major heave with the Snapon wrench I always use.

Recently I decided to "calibrate" my "major heave", which seemed to be very roughly 15 #ft (180 #in). However, with new rockers and adjusters, at a recent race, I found a nut had fallen off, so 15#ft was clearly not enough.

As a limit check, I pulled out some old rockers from my junk box. Their (probably original) adjusters started to give up the ghost around 20 #ft (240 #in). Oft specified lubed torque for 5/16-24 is 20 #ft. Tappet adjuster nuts are thinner than SAE nuts, so I am guessing they cannot take the full 20#ft torque.

I don't see a torque number in either MGA or MGB shop manuals, so can anyone suggest a reliable torque number?
Malcolm

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Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Greenville, SC, USA   USA
1967 MG MGB Racecar "The Biscuit"
Work out a bit, and you should be able to get 20 with that hand wrench smiling smiley



Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com


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Blueosprey90 Avatar
Blueosprey90 Jeff Sienkiewicz
New Milford, CT, USA   USA
Does this help? I use it unless a specific MGA torque setting is specified.

http://www.mgexp.com/article/mgb/pdf/mgb-torque-settings.pdf

malcox Avatar
malcox Malcolm Cox
Napa, California, USA   USA
Thanks for the list Jeff.
The list also does not show tappet adjuster torque values.

I got concerned when I found that a couple of original MGA tappet adjusters started to FAIL at 20-25 #ft
I am guessing that modern (from APT) adjusters would be made from grade 8 equivalent steel, so 20 to 25 #ft should not be a problem.
malcolm

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Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Greenville, SC, USA   USA
1967 MG MGB Racecar "The Biscuit"
In reply to # 3627196 by malcox Thanks for the list Jeff.
The list also does not show tappet adjuster torque values.

I got concerned when I found that a couple of original MGA tappet adjusters started to FAIL at 20-25 #ft
I am guessing that modern (from APT) adjusters would be made from grade 8 equivalent steel, so 20 to 25 #ft should not be a problem.
malcolm

The new one sold thru the vendors are junk, they are poorly made for inferior metal and way too heavily black oxide plated, even if you take the time to wire brush all that crap off, then the screwdriver slot breaks out on them I don't know what Anton sells, I never ask him, but I know Richard Goode, of Good Parts has new high quality ones made, and the Triumphs use the same adjuster we do on the MGBs, so if I need new, I get them for Richard, I have lots of used stuff lying around so I mostly use that stuff, it is very good quality, I tend to shy away from the early drilled oiling one, that is totally not necessary and they can break from the drilling, as it makes them weaker.



Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com


Member Services:
MG/ Triumph Performance Street/Race Engines - Cylinder Head Porting - Modified SU HS Carbs - DIY Engine Rebuild Kits With Free Tech Advice - Alloy wheels for British Sport Cars,and others
twentyover Avatar
twentyover Greg Fast
Lives in SoCal, Resides in the Burbs of Detroit MI, USA   USA
Another option may be to go to a specialist place. I have all my factory based rocker arms rebuilt at Rocker Arms Unlimited in Andersonvile.

http://www.rockerarms.com/

Usually have them re-ratio the rocker at the same time.

I'm pretty sure they can provide a good quality adjuster

fast-MG.com Avatar
fast-MG.com Gold Member Dave Headley
Cortez, 4 corners, Colorado, USA   USA
Greg, what method is used to re-ratio the arms?


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twentyover Avatar
twentyover Greg Fast
Lives in SoCal, Resides in the Burbs of Detroit MI, USA   USA
Angle drilling the adjuster.

Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Greenville, SC, USA   USA
1967 MG MGB Racecar "The Biscuit"
In reply to # 3627404 by twentyover Another option may be to go to a specialist place. I have all my factory based rocker arms rebuilt at Rocker Arms Unlimited in Andersonvile.

http://www.rockerarms.com/

Usually have them re-ratio the rocker at the same time.

I'm pretty sure they can provide a good quality adjuster

Greg, they chrome finish the used rocker shaft , rather than buy new, go figure that one, which make them slightly larger in OD, then ream out the bushing to fit the slightly OS shaft, nothing wrong with that until you need a new shaft. Here's the deal Harland Sharp will make you adjuster bolt custom, our ball type is somewhat rare, but HS is not going to make you 8 of them, more like a production run of them, Richard Goode never told me if that is where he was having them made but I highly suspect that is where they are being made. Bottom line our adjuster bolt are not a common piece and somewhat unique.



Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com


Member Services:
MG/ Triumph Performance Street/Race Engines - Cylinder Head Porting - Modified SU HS Carbs - DIY Engine Rebuild Kits With Free Tech Advice - Alloy wheels for British Sport Cars,and others
twentyover Avatar
twentyover Greg Fast
Lives in SoCal, Resides in the Burbs of Detroit MI, USA   USA
As you say, Hap. Not a big deal until you need a replacement shaft. So rather than going to Moss or BPNW for a replacement shaft, I go to RAU. I know they hard chrome the shaft- it took them almost two months to finish the rockers while they were waiting to accumulate enough material to make a plating run. In reality, how many rocker shafts am I REALLY going to need to replace between now and the time I start my dirt nap? I can probably rotate the shaft 180 degrees if it REALLY wears and I need to get home tonight.

I suggested them as a potential contact as I believe they would have quality adjusting screws available, as this seemed to be they way this thread was drifting. I know they have at least 16 used ones from the rocker sets they re-ratio’s for me, and the re-ratio’ed rockers use a different adjuster thread size and have a different pushrod end. Will an aluminum aftermarket rocker manufacturer have OEM style adjusters for a B motor? Not if they’re smart- aluminum should use a coarser thread to prevent pullout.


In reply to # 3627615 by Speedracer
In reply to # 3627404 by twentyover Another option may be to go to a specialist place. I have all my factory based rocker arms rebuilt at Rocker Arms Unlimited in Andersonvile.

http://www.rockerarms.com/

Usually have them re-ratio the rocker at the same time.

I'm pretty sure they can provide a good quality adjuster

Greg, they chrome finish the used rocker shaft , rather than buy new, go figure that one, which make them slightly larger in OD, then ream out the bushing to fit the slightly OS shaft, nothing wrong with that until you need a new shaft. Here's the deal Harland Sharp will make you adjuster bolt custom, our ball type is somewhat rare, but HS is not going to make you 8 of them, more like a production run of them, Richard Goode never told me if that is where he was having them made but I highly suspect that is where they are being made. Bottom line our adjuster bolt are not a common piece and somewhat unique.



Edited 1 time(s). Last edit at 2017-11-15 02:50 PM by twentyover.

Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Greenville, SC, USA   USA
1967 MG MGB Racecar "The Biscuit"
Brown and Gammon, and Harland Sharp both use stock adjuster bolts. The ones Good gets made might be the same ones, but HS s one of the very few places that manufactures them.

here's a look at them https://www.goodparts.com/shop/index.php?productID=302



Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com



Edited 1 time(s). Last edit at 2017-11-16 02:33 PM by Speedracer.


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