Stainless, Bushed PRW Rocker Arms

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Mopar69gts

Mopar69gts

FABO Gold Member
FABO Gold Member
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Hey everybody,
I wanted to post my experience so far with PRW Stainless, Bushed 1.6 Rocker Arms.
In 2019 I bought a set of Trick Flow 190's
For my 340.
Thanks to FABO I learned that the go to guy for Rocker Arms and geometry correction kits is Mike @ B3RE.
I called him and he spent quite a bit of time with me explaining Rocker Arms and geometry.
His recommendation was the PRW Rockers
Along with his correction shims to be added under the rocker shafts.
I got the complete kit from him
And I really can't say enough about his helpfulness and knowledge!
Everything went together perfectly.
The 340 picked up a ton of power everywhere!
Well after about a year and around 10k.
Miles I started hearing more and more valve train noise.
So I took off the rockers and found all the bushings were wearing out.
Leaving metal transfer on the shafts.
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I called Mike and he had me send them back to him to inspect.
He was so nice to warranty them for me.
He also suggested that I should add pushrod oiling.
He also suggested that I call PRW as well to let them know what happened.
They also suggested adding pushrod oiling.
So I changed all the lifters out to AMC style.
All went well for almost 1 year, but recently the valve train was getting loud again.
Pulled off the rockers and found number 8 exhaust Rocker arm bushing almost worn clear through.
Another one on drivers side was worn too.
Most of the others seem ok as far as the bushings go.
But now I found some of the roller tips getting flat spots and feel rough to spin with your finger.

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I called Mike and he stopped what he was doing to spend time with me discussing what was causing this.
So far he has not had many problems with PRW Rockers.
But we also discussed mine being a driver I probably put more miles on then most.
But still something is going on?
I had only been using penn grade oil
And having added pushrod oiling along with standard LA through the head oiling, you wouldn't think it's an oil issue.
Plus the cam is just a comp. Xe 268 h.
Trick flow springs @ 120 seat x 320 open.
I called PRW as Mike suggested
They said to send them pictures and they will get back to me asap.
I'll keep you guys posted...
Mike
 
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In the pics you have posted, it seems to me the rocker arm shaft oil holes are
more in line with the hold down bolt holes? Are the rocker shafts OEM or aftermarket?
Just check your shafts to make sure the oiling holes are facing to the lower side, to
the bottom edge of your valve cover, or to the exhaust manifolds or headers. If the shafts are OEM units, have you ever knocked out the end caps, and clean or have the shafts
boiled out at your machine shop? Just some FYI.
 
Well these rockers are made in China, so who knows with the quality control and what they are using to make the rockers and the bushing.
 
Not excited to see this post. I almost bought a set. I ended up using a set of old school Crane gold rockers and shafts because I beat the brakes off a 340 I had in a truck with a ton of miles and those rockers looked like new...

Keep us posted as to what the problem is.

JW
 
E7polyhachett said:
In the pics you have posted, it seems to me the rocker arm shaft oil holes are
more in line with the hold down bolt holes? Are the rocker shafts OEM or aftermarket?
Just check your shafts to make sure the oiling holes are facing to the lower side, to
the bottom edge of your valve cover, or to the exhaust manifolds or headers. If the shafts are OEM units, have you ever knocked out the end caps, and clean or have the shafts
boiled out at your machine shop? Just some FYI.
Click to expand...

The Rocker shafts are PRW that came with the kit.
The first set had oil holes on the bottom inline with hold down bolts.
The second set are drilled straight through with oil holes top and bottom.
Probably to make them fool proof.
Or maybe to help with oiling.
 
Mopar69gts said:
The Rocker shafts are PRW that came with the kit.
The first set had oil holes on the bottom inline with hold down bolts.
The second set are drilled straight through with oil holes top and bottom.
Probably to make them fool proof.
Or maybe to help with oiling.
Click to expand...
Oil hole in the top is of no value, you want to get the oil to the rockers main friction point, which is obviously the bottom. Widest clearance between the rocker and the shaft will be at the top. If the oil can escape there first, then it will.
You then want to spread oil across the bush, that's where a small oil groove comes in. Then you need to make sure it's getting enough oil.
 
Realistically a well controlled full time oil supply to the rockers is the best way to go, in my opinion.
 
Sorry for the rapid fire questions…not expecting answers back, just food for thought.

How much preload do you run? Do you check it/adjust it often? Do you ever get valve toss when you get on it hard? Have you run an oil pump prime with the valve covers off to make sure you’re getting oil in the shafts? Maybe the feed hole from the cam is choked down or blocked. Also check hole direction as others have mentioned.With the issue seemingly isolated to specific cylinders, have you checked those particular valves and guides? Maybe something is off, like they’re sunk a little deeper or shallow than others so their geometry is a little different…not all machine shops equalize the heights, or the guides are a little tight and have to get “run in”. Bolting on heads out of the box without set up from a machine shop can have some of those issues.

I run these rockers too, but really only at the strip, and with a solid flat. Wondering if too much preload was keeping the roller in the same spot vs with lash where it unloads and spins with every cycle.

I think it’s pretty awesome you put so many miles on it. Could just be crappy materials that were meant for the average classic that only goes out on nice weekends. All the best to you on your quest!
 
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Just looking at your pictures , it sure seems that you have an oiling issue ! I guess the question is why ? I’m thinking the second set would have looked just like the first set with the same time and mileage on them ! Most definitely keep us posted on what you find out Sir……
 
Bakerlite said:
Oil hole in the top is of no value, you want to get the oil to the rockers main friction point, which is obviously the bottom. Widest clearance between the rocker and the shaft will be at the top. If the oil can escape there first, then it will.
You then want to spread oil across the bush, that's where a small oil groove comes in. Then you need to make sure it's getting enough oil.
Click to expand...

I also agree with Bakerlite.....as the bushing would benefit tremendously if it was
cut with a groove! Does the OP know if the main rocker shaft is made of some type
of stainless steel? I am now wondering what the Chinescans were/or are using for
the inner rocker bushing? There are many types of bronze out there..... and for
what it is worth, are they using 100% oillite bronze for the production of these
rocker bushings? IMHO, by me viewing the rocker shafts (I am 60yo in two mos) eyes
are getting worn out) but the pics do show some different heat coloring on many areas
of them, which makes me think, these bushings are not made out of 100% bronze?
Maybe, some kind of other ionized powdered metal, or some other, ferrous metal mixed in. IDK?? Something is going on! I will run this situation by my 6 different machinist friends, and see what they all have to say. I will check thread tomorrow, as I do not want a headache before bed tonight.
 
No worries
Dusterbing the peace.
Thanks for the questions,
I use 1 turn down from zero lash.
I do check over everything often
It's getting a lot of oil especially since adding pushrod oiling.
These shafts are not like factory, in that the oil holes are not at an angle.
No orientation, just down.
The second set I have now have oil holes on top and bottom so you can't install wrong.
Thank you.
 
toolmanmike said:
Check these shafts out. Note the orientation of the oiling holes vs the bolt holes and the oiling grooves. These are nice pieces. [FOR SALE] - Small Block Rocker Arm Shafts for Adjustable Rockers - New
Click to expand...
Thank you
I have been looking at those.
I called RAU and spoke to Gary
He also spent a lot of time with me discussing this situation.
He said he'd be happy to check them over free of charge.
He said to re Bush them and have the shafts hard chromed would be $380
But then I saw the roller tips wearing flat.
So I don't know if their worth fixing.
If nothing else I'm getting to talk to a lot of really Cool and dedicated people!!
 
Another question, pushrod oiling? Where does the oil go when it gets to the adjuster on the rocker? (I know the answer)
 
The shafts need the nanner grooves in order to run that style rocker.
 
toolmanmike said:
Another question, pushrod oiling? Where does the oil go when it gets to the adjuster on the rocker? (I know the answer)
Click to expand...
These Rockers have a oil hole in the adjuster that feeds a hole in the rocker to the shaft.
I get what you're saying though if the adjuster and Rocker had no holes it would do nothing...
 
Mopar69gts said:
Yes
Click to expand...
Then the only thing left is the lack of nanner grooves. Am I seeing that right that all of the wear is on the bottom of the shafts and the bottom of the bushings? The lack of those grooves is keeping a good oil cushion from happening, imo.

I would also include maybe a bad batch of the bronze bushings, but it would have had to happen twice now wouldn't it?
 
RustyRatRod said:
Then the only thing left is the lack of nanner grooves. Am I seeing that right that all of the wear is on the bottom of the shafts and the bottom of the bushings? The lack of those grooves is keeping a good oil cushion from happening, imo.

I would also include maybe a bad batch of the bronze bushings, but it would have had to happen twice now wouldn't
Click to expand...

I think that banana grooves would help.
I did put on a set of 273 rockers with banana grooves now so I can still drive it.
I also did that after the first time and after taking them off they show no wear at all.
And they have cup and ball pushrods with no oiling?
So that tells me it's probably not my Engine/oiling...
Also the roller tips wearing flat is a whole other thing too...
 
Mopar69gts said:
I think that banana grooves would help.
I did put on a set of 273 rockers with banana grooves now so I can still drive it.
I also did that after the first time and after taking them off they show no wear at all.
And they have cup and ball pushrods with no oiling?
So that tells me it's probably not my Engine/oiling...
Also the roller tips wearing flat is a whole other thing too...
Click to expand...
The roller tip wear could be related. Without nanner grooves, there's a lack of oil. I would be inspecting everything about those rockers and shafts. Look very closely at all of the oil passages. If you weren't having pushrod or adjuster wear, I tend to agree you don't have an oiling problem from the engine. I would also make dang sure you have enough oil coming from the engine to the shafts. I bet you do.
 
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