273 rocker arm adjustment

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BTW, the 2 holes in the rockers don't line up with the 2 holes in the shaft.
- There is a bottom hole in the shaft with the banana groove; there is no matching hole in the rocker there.
- There is a small top hole in the rocker but no matching hole under it in the shaft; if open, this top hole just dribbles a little oil out that eventually finds it's way onto the valve stem tips.
- The only place where there are holes in the shaft and rockers that come close to lining up is on the uphill (pushrod) side of the shaft where the matching hole to the adjuster resides. This is where the matching of the holes may be useful. (I am of the opinion that if these 2 holes pass each other at sometime during the valve lift cycle, that will be adequate for most typical uses; spring pressures at or under 300-400 lbs and maybe RPM at or below 7k.)
 
Rapid Robert said:
I just saw a new set of the ball/cup pushrods with slight surface rust on Moparts for $25
Click to expand...

Where do i find that? i did a google search and couldnt come up with anything.

Summits website is down today for some reason.

nm9stheham said:
BTW, the 2 holes in the rockers don't line up with the 2 holes in the shaft.
- There is a bottom hole in the shaft with the banana groove; there is no matching hole in the rocker there.
- There is a small top hole in the rocker but no matching hole under it in the shaft; this top hole just dribbles a little oil out that eventually finds it's way onto the valve stem tips.
- The only place where there are holes in the shaft and rockers that come close to lining up is on the uphill (pushrod) side of the shaft where the matching hole to the adjuster resides. This is where the matching of the holes may be useful. (I am of the opinion that if these 2 holes pass each other at sometime during the valve lift cycle, that will be adequate for most typical uses; spring pressures at or under 300-400 lbs and maybe RPM at or below 7k.)
Click to expand...

I am getting a set of 273 rocker arms and shafts from Jon monday, and then i will have to look at this stuff closely. I might have to upload some pictures for verification to make sure i am on the same page.
 
The bottom of the rocker shaft where the Banana Groove is, is where the majority of the whole load of the spring, the valve, the pushrod and the cam lobe, pressure is exerted. All valve train load is at the bottom and side of the shaft during the cycling of the valve. So the need for the groove especially when using high-lift cams with lots of spring pressure.
 
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so i got the complete set of 273 valve train...these also only have one hole per rocker, and no banana grooves. Also looks as if they have the same galling marks that i have.

Looks like i am just going to have to drill holes and add banana grooves.

I have a nice big swing drill press at work, i can put the shaft in the vice and square it up and drill those holes pretty easy. i guess the hard part is deciding where to put the holes and what size holes.

The banana grooves i can make with a small abrasive wheel on a die grinder. the very bottom hole needs the banana grooves?

What about plugging/drilling holes in the rocker arms?

Once i get all the drilling done i can polish the arms and shafts to make them pretty smooth again.

What is the consensus on all this fine stuff.

Looks like i will just have to run those push rods from summit.

Thanks yall
 
I just looked on moparts & could not find them (& I just saw em yesterday!) a new set for $25 from Joel in edinburg Pa. yes add the banana grooves on the bottom 15 deg offset holes. I would plug the side shaft holes (they're clocked wrong) by soldering & add new ones in the side of the shaft/rocker to oil the cup and the valve (hole in rocker is already there on pushrod side & cap the large outer hole on pushrod side that is used by Ma to access this inner hole that is already there & cap the top hole (273 iron adj rockers). I get the cam on base circle & drill thru rocker/shaft at that point so there is some dwell time for the oil to shoot out.
 
What are you guys running for push rods?

Is there anyway you guys can make a drawing or some good pictures? My brain starts hurting after a long day at work. I keep confusing my self with where to plug and where to drill.
 
braze shut the top rocker hole. drill/tap/plug the outer 9 o'clock hole when done drilling thru (past) the inner hole (which is already there) & on thru the shaft. drill a hole thru the rocker/shaft at the 3 o'clock (right hand side) location. drill em (.100") with the cam on base circle. solder shut the small "side" holes in the shaft (you see two of em in the pic)

SAM_0499-001.JPG
 
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Rockers:

braze shut the top rocker hole, ok, what brazing material/method have you found works best? Also with the top hole plugged, how does the top of valve and tip of rocker get oil?

I found a 7/64 drill bit fits (little under .100") fits nicely in the two holes for the valve lash adjuster threaded bore (the 2 holes on the left), so using those two holes as a guide, drill through to the other side of the rocker on the right? Then drill tap and plug the most outer hole on the left of the valve lash adjuster threaded bore? that makes sense to me because it will help keep oil going to the top cup of the push rod which is my problem area.

Rocker pivot shafts:
uhhhhhhhhhhhh oh boy im going in circles here, how do i drill when im on the base circle of the cam?

the shafts pictured have two holes, am i going to end up with two holes?

I should have a hole with banana grooves right where the galling is happening.?

the rocker arm pictured, has 4 holes and the shaft has two holes

sorry guys...i feel like a retard ...i may need some more step by step instructions with pictures...
 
i also still haven't figured out what i am going to do for push rods...everyone online only has 9 of the RP-3159 push rods, so that must mean they are getting them from the manufacture and that all they have? i dont know why its so hard to get these push rods, there has to be something else out there available? I dont want to change the length either because i am getting a really nice pattern on the rocker tips. I need to get some push rods by next weekend so i can get this thing running.
 
70dart65coronet said:
i also still haven't figured out what i am going to do for push rods...everyone online only has 9 of the RP-3159 push rods, so that must mean they are getting them from the manufacture and that all they have? i dont know why its so hard to get these push rods, there has to be something else out there available? I dont want to change the length either because i am getting a really nice pattern on the rocker tips. I need to get some push rods by next weekend so i can get this thing running.
Click to expand...

If you can get them a good drawing to work off of so there is no confusion on how to measure the length, this place had ours shipped to our door within 3 days (and were cheaper than most of the pre-made ones):

The company that he used was OE Push Rods and they cost about $65 per set...

Home - OE Push Rods - Manufacturer & Distributor
 
70dart65coronet said:
Rockers:

braze shut the top rocker hole, ok, what brazing material/method have you found works best? Also with the top hole plugged, how does the top of valve and tip of rocker get oil?

I found a 7/64 drill bit fits (little under .100") fits nicely in the two holes for the valve lash adjuster threaded bore (the 2 holes on the left), so using those two holes as a guide, drill through to the other side of the rocker on the right? Then drill tap and plug the most outer hole on the left of the valve lash adjuster threaded bore? that makes sense to me because it will help keep oil going to the top cup of the push rod which is my problem area.

Rocker pivot shafts:
uhhhhhhhhhhhh oh boy im going in circles here, how do i drill when im on the base circle of the cam?

the shafts pictured have two holes, am i going to end up with two holes?

I should have a hole with banana grooves right where the galling is happening.?

the rocker arm pictured, has 4 holes and the shaft has two holes

sorry guys...i feel like a retard ...i may need some more step by step instructions with pictures...
Click to expand...
Your fine brother. I ain't a welder & I had my shop take care of that part. with the top hole brazed shut the holes we will add (3/9 o'clock with the mini file stuck into em in the pic to show where) will take care of the valve tip/pushrod tip. A 7/64 bit is fine. the rockers already have an inner hole on the pushrod side for oil to dribble down to the pushrod & a large outer hole on that same side that was needed to access/drill that inner hole & after you drill on thru the already there inner hole & on thru the shaft then the outer hole is drill/tapped/plugged shut as it is a leak & no longer needed. paint the shafts lengthwise on each side with Dykem & mockup & with the pushrods out so you are in effect on base circle on all of em (with you holding the rocker so it touches the valve tip on the other side) stick a thin scribe with a straight shank on the end (HF has just what you need) & scribe a little "circle" in the dye on the shaft and on the spring side do the same thing with a scribe with a 90 deg bend on the end cuz the spring is sorta in the way, thru the hole you have already drilled in the rocker (3 0'clock position) & mark the shaft then remove everything & drill the shafts for the holes in the dye on both sides. BUT FIRST before scribing, use rocker shaft thin shims (Hughes & others have em) to locate the rockers laterally on the shafts in addition to the OE thick spacers so there is .015" clearance side to side per pair & also the 5 hold downs are a bit oversize so there is some wiggle room there & this is the time consuming part is adding/juggling shims/holdowns till each pair of rockers are CENTERED on the valve tips with the .015" clearance per pair till you get each rocker dead on & scribed then undo everything & drill the rockers & the shafts in the dye & deburr the shaft ID when done drilling. The "side" oe holes in the pic are clocked wrong & should be soldered shut. you keep the holes in the banana grooves & when mocking up be sure to have the notch down & to the rear on the pass side & down & to the front on the drivers side. take alot of care to get it mocked up DEAD ON before you reach for the scribe. for final assy you would adj everything side to side till the holes line up before you evenly tighten/torque the (5) holdown bolts. I like to get the rocker arm adjusting screws adjusted for the vertical pushrod cold clearance I want THEN remove the rockers & goop the lobes then reinstall the rocker assys & go thru the side to side clearance setting but that's just me & my OCD. YMMV! but cam failures are epidemic & I want the lobes lubed good for startup along with light spring pressure for breakin
 
Ok I'm following all that except, my shafts only have 1 hole per rocker and without banana groove.

I am going to solder that one hole shut, and add two holes, locations transferred from the two holes in the rocker arm on base circle of cam

So I won't have an hole where the bottom of rocker shows all the galling? How does that area that is taking all the load get oil.

I understand how the rocker arm adjuster tip and valve tip get oil now.

But how do we oil the very bottom of the rocker where the galling is happening? I will end up with two new holes in the rocker, which one do I add bana a grooves too.?
 
How do the bearing surfaces of the rockers get oil? Oil pressure forces oil thru the tube, out the holes, and oil fills all the small spaces between the tube and the rocker arms. This is the same way any other bearing(s) in the engine work... ideally, everything is riding on a film of oil and there is no metal-to-metal contact.
 
ok this is what i came up with, double check my procedure

#1 fill the top hole of the rocker arm using brazing material. (many different methods, just avoid putting to much heat into the rocker arm)

#2 using the two existing holes in the valve lash adjuster threaded bore as a guide, drill through to the other side of the rocker using a .100" drill bit, #38 drill bit. This will put a hole under the rocker arm tip, which will shoot oil out onto the top of the valve stem/rocker tip. At this point there will be three holes in the rocker. Later on we will plug the outside hole of the valve lash adjuster threaded bore using a drill, tap, and set screw with lock tite.

#3 need to locate the rockers laterally on the rocker shafts. Center rocker on each valve tip on rocker shafts using additional shims. .015" per pair of rockers. so the order goes like this: rocker shaft clamp with bolt, then a gap, then a rocker arm, gap, stock rocker arm spacer, gap, rocker arm, gap, clamp with bolt. so those four gaps need to add up to .015", in which ever order is necessary to get the rocker arm tips centered on the valve tips. set it up with best judgement, and then put some dykem on the valve tips, rotate the engine and check the pattern. once all the patterns are good, make a diagram of how to put it back together.

#4 solder shut the existing one hole in the rocker shafts, polish, and then paint dykem on the shafts lengthwise on each side (where the 2 holes in the rocker arms are). re assemble using the diagram made in step 3 without push rods. hold the rocker tips on the top of the valve tip, this represents being on the base circle of the cam where there is no load on rocker arm from the valve springs. this will allow the oil to rush in when there is no load (larger gaps). While holding the rocker arm onto the valve tip, stick a thin scribe with a straight shank on the end and scribe a little circle in the dye on the shaft, and then on the spring side do the same thing but you will need to use a 90 degree scribe because the spring is in the way, through the hole in the rocker arm that we drilled underneath the rocker tip. Mark all 8 rockers (total of 16 holes), take the assembly apart, remove the rockers from the shafts and drill them with a #38 drill bit, the hole towards the bottom, add the banana groove, de bur, berry hole and polish everything. Also now we can drill tap and plug that outer hole in the rocker arm with a set screw and loctite.

#5 for the final assemebly adjust everything side to side till the holes line up before you evenly tighten/torque the 5 hold down bolts. Set the valve lash cold with no lube, then take them all part and lube everything up, then double check the side to side clearance.

here are the items that i am going to buy:

rocker arm shaft side shim kit (i think i need to get two sets?):

Amazon.com: Mopar Performance P3690896 SPACER PACKAGE: Automotive

the locking adjusters:

Amazon.com: Crane 99802-16 Shaft Rocker Arm Adjusting Screw - Pack of 16: Automotive

This is the end mill im going to use at work to mill the top of the rocker arms for the locking adjuster nuts. I can use the threaded bore for the valve lash adjuster, to bolt it perfectly to the milling machine table, then bring the end mill down to the top and just touch it until it has removed enough metal to be true.:

https://www.amazon.com/gp/product/B004KA99PI/?tag=joeychgo-20

number #38 drill bit:

Century Drill and Tool 11438 Wire Gauge Drill Bit, NO 38 - Jobber Drill Bits - Amazon.com

blue dykem:

Dykem 80300 Steel Blue Layout Fluid, Brush-in-Cap (4oz): Amazon.com: Industrial & Scientific

Adjustable push rod for measuring the custom push rods:

https://www.amazon.com/gp/product/B001G9HWCI/?tag=joeychgo-20

Picture attached:


wow that was a keyboard full, howd i do?

20170812_162209.jpg
 
Sounds like a new Bible on this! LOL

One possible issue: I think RR's point on the location and angle of the hole on the valve tip side is different than yours. Your sketch seems to show it in-line with the hole on the pushrod side, and your step #2 describes it that way. I think his point was to angle it so that it is as close to tangent to the rocker-to-valve surface as possible. Your sketch seems to show it at too low an angle and too far down on the side of the rocker body, so that it may well miss the top of the valve/retainer, and become useless.

I am going to make one suggestion and see what RR and everyone one thinks. The valve tips need relatively little oil, and if both of the holes (for both the pushrod cup and the valve tip) line up when the valve is closed, I would be a bit concerned that there is too much flow potential out of the shafts for the flow into the shafts to support. Remember, the flow into the shafts is already restricted in 2 places, so you end up with low pressure inside the shafts to start with. So putting too much flow to the valve tip may take oiling away from the pushrod cup.

So, I think that moving the valve tip side hole on the shaft down a bit would be helpful. Move it down by an amount that is a bit more than the diameter of the hole, so that it is closed off when the valve is closed, but it opens twice per valve cycle. This would regulate the valve tip flow to a lower amount.
 
ok here is a couple more pictures, when i first read RR's method it sounded like he was running the drill bit through the two push rod holes (using those two holes like a drill guide)

I think my drawing got a little wonky and i was confused about RR's picture because the two files he stuck in the rocker arm holes were at two different angles, but i think that was just because the file handles fit loose in the holes and he was just making a demonstration?

anyway, here is a drill bit that fits nice and tight, and it makes a straight shot to the other side, see how i lined up the drill bit with the ruler with the circle square tool.

20170813_095108.jpg


20170813_095227.jpg
 
i see what you mean about how if those two holes are lined up at the same time...the oil pressure inside the rocker shaft will drop. i kind of like your idea of drilling the hole under the rocker arm at a different angle, so it doesn't line up with the other side. I drew a red drill bit onto the previous drawing, is this what your thinking? i looks as if the two holes will still end up being pretty close to the same spot.

20170813_100841.jpg
 
Yes, your red drill line is what I think RR meant and which makes the most sense to me. I did a similar thing on a set of PRW needle rockers. In the 1st photo, you can see how it was jigged up using a 7/8" maple dowel to hold the rocker. The 2nd shows the hole for the valve tip side straight on, and how it juuuust passes the rocker tip on a tangent.

Flow was a constant dribble to the valve tip hole in that setup due to the internal restrictions, and no way to regulate it. Way over kill for the valve tip, but those PRW AL needle rockers had no oiling to the roller axle so I felt I had to get oil there somehow.

DSCN1763.JPG


DSCN1766.JPG
 
wow that was a keyboard full, howd i do?
Click to expand...
Pretty good. Some slight corrections: the banana grooves would go in the shafts at 6 o'clock across the already there 15 deg offset holes (If I was reading that situation correctly). the hole in the rocker on the valve tip side that goes out toward the rocker arm/valve tip interface needs to further up like in my pic/& was commented on later as opposed to being in a straight line from the other side. I turned the cam bearings to block flow up to the heads (cam bearings are a notorious leak) & I drilled thru each angled gallery on each side of the valley & on down into the main galleries so they are being fed full time then up at each deck I drilled/tapped into each oil gallery (the top of the 2 angled passages) for a setscrew drilled to 0.0625" . Point taken on 0.100" being too much for the valve tip side (I'll reduce it on my next one). The shaft bottom (6 o'clock) holes are much larger on a non banana grooved shaft than they are on an OE banana grooved shaft & may or may not need reducing & on an earlier Q, with the shaft haveing 3 holes now, I think the load bearing arc fulcrum should be getting plenty of lube. #1#1#1 get everything mocked up DEAD ON before scribeing the dykem (you dont want to have to do it again!) EDIT & I drilled new holes in the cam bearings vertical from the mains, 1/16" which is plenty for them
 
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ok i will digest this and reformulate the procedure for review.

unfortunately my engine is together and in the car, so i cant change the cam bearings at this point, but that is good info. Do you think i will be ok with the stock setup of the cam bearings?

.100" too much for the valve tip side? what do you guys think it should be? do we need to change that hole size in the shaft also?

There is alot to this stuff and i want to do this stuff right the first time... i have two more weekends before the big car show at silverwood. i got alot of technical work to do...hows that smokey and the bandit song go...

thanks
 
IMHO, if you offset the oil hole in the rocker shaft from the oil hole in the rocker slightly when the rocker is at rest (lifter on base circle), so that there are just a spurt, or spurts, of oil per valve lift cycle, then I'd stick with the .100" hole or so. You don't need a ton of oil there but the timed spurts ought to give some oil control.
 
I got the top hole of the rockers brazed, i used silicone bronze tig rod and tig brazed them, it went ok.

I ended up using the same method to plug the holes in the shafts, it went ok until i was machining the welds down smooth in the lathe when i realized the shafts are chromed and the lathe chipped a bunch of chrome off, ughhh....so then i had to fill that in with more silcone bronze, and switch to smoothing the welds down with a belt sander...eekkkk. Then i took it to the polish grinder and smoothed them out, i think it will be ok... i cant believe those are chromed...that was a PITA

RR what do you mean the shaft having 3 holes? i had one hole, now i have zero holes, and i need to drill two holes and add a banana groove on one of those holes at 6 o clock

i still need to update the procedure we have been formulating for drilling the rocker arms and shafts, but before i do that i am trying to get my push rods figured out, so i can get them here so i put this thing back together next weekend.

krazykuda said:
Rob, can you list the part number for the crane replacement adjusters and nuts???

Let's get all the info in one thread as many people like to run the stock 273 adjustable rockers on hydraulic cam small blocks...

Then maybe OE Push Rods can assign a part number and can make them available for everyone...
Click to expand...

Do you know if this ever happened?

I have the comp 7709 push rod checker and i am having a heck of a time using it. When the checker is in the head you cant grab the lower half to adjust it. (its really hard to do in the car, since i am dealing the previous owners oversights)

The ones on the end are easy, because where the push rod checker goes through the head its thinner. also PITA you have to take the complete rocker shaft assembly each time because there is no way to get the push rod checker in there each time.

I have four measured so far with a average of 7.123" from end of ball to end of cup. The ones he had in there were 7.382" (sealed power RP-3159) ! its no wonder the cups were digging into the rocker arm.

The other thing that sucks with this setup is you cannot adjust the geometry of the rocker. These flat tipped rockers have a huge drag surface compared to a roller rocker. but i believe to change to that setup you have to have major machine work done to the heads.
 
I suspect most folks use the checker pushrod during assembly with the intake manifold off.

Chromed? Maybe some sort of surface hardening?
 
70dart65coronet said:
I got the top hole of the rockers brazed, i used silicone bronze tig rod and tig brazed them, it went ok.

I ended up using the same method to plug the holes in the shafts, it went ok until i was machining the welds down smooth in the lathe when i realized the shafts are chromed and the lathe chipped a bunch of chrome off, ughhh....so then i had to fill that in with more silcone bronze, and switch to smoothing the welds down with a belt sander...eekkkk. Then i took it to the polish grinder and smoothed them out, i think it will be ok... i cant believe those are chromed...that was a PITA

RR what do you mean the shaft having 3 holes? i had one hole, now i have zero holes, and i need to drill two holes and add a banana groove on one of those holes at 6 o clock

i still need to update the procedure we have been formulating for drilling the rocker arms and shafts, but before i do that i am trying to get my push rods figured out, so i can get them here so i put this thing back together next weekend.



Do you know if this ever happened?

I have the comp 7709 push rod checker and i am having a heck of a time using it. When the checker is in the head you cant grab the lower half to adjust it. (its really hard to do in the car, since i am dealing the previous owners oversights)

The ones on the end are easy, because where the push rod checker goes through the head its thinner. also PITA you have to take the complete rocker shaft assembly each time because there is no way to get the push rod checker in there each time.

I have four measured so far with a average of 7.123" from end of ball to end of cup. The ones he had in there were 7.382" (sealed power RP-3159) ! its no wonder the cups were digging into the rocker arm.

The other thing that sucks with this setup is you cannot adjust the geometry of the rocker. These flat tipped rockers have a huge drag surface compared to a roller rocker. but i believe to change to that setup you have to have major machine work done to the heads.
Click to expand...

Here are the Crane adjusting studs and nuts:

https://www.summitracing.com/parts/..._-crane-cams&gclid=CPC0zrX8lNICFYQvgQoduD0N4g

The two other threads can give you the end dimension that we used...
 
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