318 LA Engine Rocker shaft help needed.

[Mike69barracuda]

Subject engine: 318 LA Engine Rocker shaft

1. I replaced the worn rocker shafts with NOS 318 shafts. Also rocker arms, flat tappet lifters and push rods. My Question -- The org. rocker shafts had end plugs. The NOS rocker shafts have no end plugs. Do I need to find some??? Any sources where to buy the rocker arm shaft plugs???

2. Also my factory service book says torque the rocker shaft retainer bolts down to 200 inch pounds?? The long retainers are in position 2 and 4 on both sides. The slot on the shafts are pointing in the correct direction. THX

 

[pishta]

they need plugs. There is pressurized oil in there and it wont flow to arm fulcrums if its rolling out the ends. They are just a core plug, take it to NAPA and see if they have any in the drawers.

 

[Mike69barracuda]

they need plugs. There is pressurized oil in there and it wont flow to arm fulcrums if its rolling out the ends. They are just a core plug, take it to NAPA and see if they have any in the drawers.

Thank you.

 

[Mike69barracuda]

Thank you.

The guy at Napa could not find any. My original plugs are small and are brass looking.

 

[4spdragtop]

Machine shop? Home depot lowes, plugs should be accessible.

 

[Tooljunkie]

Machine shop could turn you some brass plugs to press fit.

 

[4spdragtop]

I have a set of shafts if need be.

 

[nm9stheham]

The guy at Napa could not find any. My original plugs are small and are brass looking.

Any thing that will hold oil will do. The pressure in the shafts is not very high, not anything nearly like full oil system pressure. You could thread them as suggested, a few threads, and use red locktite to seal in a bolt for a few threads and cut the rest off.

 

[Jadaharabi]

I got mine from Oreillys.

 

[Treblig]

Any thing that will hold oil will do. The pressure in the shafts is not very high, not anything nearly like full oil system pressure. You could thread them as suggested, a few threads, and use red locktite to seal in a bolt for a few threads and cut the rest off.

Aren't the rocker shafts hardened??? If so they will be hard to thread??

 

[Rocket]

I got some plugs at Advance Auto. They are 5/8” valley plugs. They are a little thicker that the stock plugs so they are tougher to press it but I managed. It helped a little to heat the shaft up in the oven and freeze the plugs overnight.

If they start asking you for what year, make and model car cut them off and ask to see their 5/8 galley or frost plugs. Show them some pictures

 

[pishta]

Aren't the rocker shafts hardened??? If so they will be hard to thread??

I dont think the hydro shafts are hardened. The Mechanical shafts are chromed or surface hardened? The shafts you get with true roller bearing lifters are hardened IIRC

 

[70aarcuda]

whole shaft and nothing but the shaft...

Sealed Power Rocker Arm Shafts RS-626

 

[Mike69barracuda]

I got some plugs at Advance Auto. They are 5/8” valley plugs. They are a little thicker that the stock plugs so they are tougher to press it but I managed. It helped a little to heat the shaft up in the oven and freeze the plugs overnight.

If they start asking you for what year, make and model car cut them off and ask to see their 5/8 galley or frost plugs. Show them some pictures

View attachment 1715214921 View attachment 1715214922

Roger that. Advanced ordered me 4 welch plugs 5/8" this afternoon. Hope to get them tomorrow. good tips on heat and freezer the plugs. THX

 

[OL DODGE]

And throw out those damned stock grade 5 rocker shaft hold down bolts and replace them with grade 8 so that when you do torque them down (like you should) they won't snap off.

 

[nm9stheham]

Just don't torque them to the mistaken FSM value of 30 ft lbs, but keep it to 15-18 ft-lbs or so, and grade 5 will be fine.

 

[T56MaxTorq]

I threaded a set, huge PIA. Before you throw the plugs in, run a 12 gauge bristle brush through them thoroughly and then use your patches/mop to clean up the rest. You won’t believe the crud that comes out.

Start with the center bolt and work outwards, 1 or 2 turn increments til you hit torque.

 

[Mike69barracuda]

I got some plugs at Advance Auto. They are 5/8” valley plugs. They are a little thicker that the stock plugs so they are tougher to press it but I managed. It helped a little to heat the shaft up in the oven and freeze the plugs overnight.

If they start asking you for what year, make and model car cut them off and ask to see their 5/8 galley or frost plugs. Show them some pictures

View attachment 1715214921 View attachment 1715214922

I picked up 4 today from Advance Auto. THX

 

[pishta]

put the plug on the floor and place the shaft over it and tap the shaft into the plug with a brass hammer or wood block, just to get it straight in. Probably a lot of coke in there as its a blind passage for the oil. My 6 valve train was covered in what looked like charcoal.

 

[Mike69barracuda]

put the plug on the floor and place the shaft over it and tap the shaft into the plug with a brass hammer or wood block, just to get it straight in. Probably a lot of coke in there as its a blind passage for the oil. My 6 valve train was covered in what looked like charcoal.

I did that yesterday. Thanks. Worked well.

 

[nm9stheham]

FWIW.... My one concern with the heavier-than-factory end plugs may be with any 273 or other adjustable rockers, in case the ends of the shafts expand a bit. Stamped rockers ought not be any issue wiht that.

 

[pishta]

They are oil cooled and they will only get as hot as the oil. Plus the freeze plugs are friction fit and never lose their small amount of outward tension on the shaft ID. The ID of a .750 ID steel shaft heated from 77F to 220F increases 001. That's more than the removed OD of a .750 cup type expansion plug. Even if the ends weeped a small amount of oil, it would not affect the shaft oiling.

 

[Treblig]

They are oil cooled and they will only get as hot as the oil. Plus the freeze plugs are friction fit and never lose their small amount of outward tension on the shaft ID. The ID of a .750 ID steel shaft heated from 77F to 220F increases 001. That's more than the removed OD of a .750 cup type expansion plug. Even if the ends weeped a small amount of oil, it would not affect the shaft oiling.

The plugs expand (with heat) with the rocker shaft so the amount of press fit doesn't really change much unless you have dissimilar metals (aluminum/cast iron or steel/aluminum). Treblig

 

[Mike69barracuda]

The plugs expand (with heat) with the rocker shaft so the amount of press fit doesn't really change much unless you have dissimilar metals (aluminum/cast iron or steel/aluminum). Treblig

Thank you. I had to tap the plugs in pretty good using a small socket. I have them seated just like the old ones.

 

[Wyrmrider]

agree with the above
in any case plugs are far enough from rocker to not make any difference
more important is clean ID on the shafts
the drilling sometimes leaves burrs