Dirtslinger
Member
I did a search and found some info on the palnuts. Im in the process of rebuilding a my 8ba and I really don't like these things, haha. Should I just use Chevy ARP rod nuts? Or can I just run the stock nuts without the Palnuts?
8ba palnuts
- Thread starter Dirtslinger
- Start date
cadillac512
Well-known member
The Chev nuts are a good plan. I used the stock Ford OE nuts and skipped the Pal nuts...they do nothing in my opinion.
Dirtslinger
Member
Looks like Speedway sells ARP nuts, I'll go with those, thanks.
Pete
BANNED
Dirtslinger
Member
I couldn’t find them on Amazon but they are on eBay and speedway. Btw, they also sell the main cap bolts.
Speedway sells the arp rod nuts and main bolts.
Speedway sells the arp rod nuts and main bolts.
Dirtslinger
Member
Another question: speedway says that loctite is recommended, how would one install these with oil in the bolt and loctite?
Ronnieroadster
Well-known member
Actually ARP hardware requires a special lube which they supply so the torque setting is correct. Using oil on any ARP hardware will not produce the correct torque desired per their instructions.
Ronnieroadster
Dirtslinger
Member
I’m assuming this doesn’t come with the Rod nuts? Thanks for the help.
Ronnieroadster
Well-known member
Sadly it doesn't but ARP has a small sample tube that maybe you can get directly from them. They usually give out these small samples at trade shows they attend.
Pete
BANNED
As a side note on the "Chev" type nuts, the proper name for them is "Marsden".
These are the ones with the very narrow slots across the back side. THESE ARE NOT COTTER PIN SLOTS.
The way these work is, the contact face is relieved slightly on the thread or inside so when tightened the clamping force is applied to the outer edge of the face causing the upper area where the slots are to turn in and apply pressure to the stud.
The more tightening torque, the more gripping force.
They always come heat treated to grade 8 or more.
As with any fastener, they should always be installed with the proper lube.
( ARP moly lube or EP gear oil)
HARD flat washers are ok under these but not normally required unless they are being tightened against aluminum or other soft material.
Marsden nuts can also be had at Caterpillar parts departments and industrial fastener companies.
These are the ones with the very narrow slots across the back side. THESE ARE NOT COTTER PIN SLOTS.
The way these work is, the contact face is relieved slightly on the thread or inside so when tightened the clamping force is applied to the outer edge of the face causing the upper area where the slots are to turn in and apply pressure to the stud.
The more tightening torque, the more gripping force.
They always come heat treated to grade 8 or more.
As with any fastener, they should always be installed with the proper lube.
( ARP moly lube or EP gear oil)
HARD flat washers are ok under these but not normally required unless they are being tightened against aluminum or other soft material.
Marsden nuts can also be had at Caterpillar parts departments and industrial fastener companies.
rotorwrench
Well-known member
Robinson Helicopter Co holds their aircraft control systems together with lock nut/pal nut combinations. The FAA requires two locking features on fasteners for flight control connections so Robinson chose the MS21043 series lock nuts and MS27151 series pal nuts in appropriate sizes. They might be a PITA but manufacturers still use them. It's mostly to save weight plus NO Cotter Pins to deal with. They only use cotter pins on the blade bolts.
Ken/Alabama
Well-known member
So what’s the problem with 3/8” Chevy lock nuts from the parts house ? I’ve been using them for years.