Speedmaster Stainless Rocker Arm Bushings

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JedIEG

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I bought a set of Speedmaster stainless rockers during the black Friday sale. I knew they weren't going to be perfect OoTB (swarf, deburring etc.) but the bushings have me a little concerned. I can clearly feel, with my fingernail, the machine turning lay on the ID of bushing. This is the first set of rockers I have dealt with at this price point so I dont have a good reference. I have run my finger over a couple of other parts with bushings I have on hand and they dont have nearly the roughness of these rockers so that has me second guessing the reliability.

Any experience with this or if I am worried about nothing? Any ideas where to get replacement bushings if needed? (I would prefer switching to a full width bushing instead of the two piece bushing they come stock with if I needed to replace them)
 
Chances are the bore in the arm is too small and pressing the bushings in collapsed them and they were resized by reaming them. So buying new bearings may also collapse when pressed in. You could buy a hand reamer and accurately size them, but it would still have some tooling marks but not as much as a production reamer. I would look at the carr McMaster web site or Grainger website.
 
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mike the bores, then either, run a brake hone through them or hone them on a rod sizing machine. i've done both.
 
the rod hone would be better for two piece bushings. have to hone lightly to clean surface, just food for thought.
 
Not looking for an argument, but I disagree with using a hone or any other abrasive tool to size a bearing. Bearing material is too soft and will get imbedded with abrasive leading to wear.
 
Thanks for the suggestions. I'm dont have a rod hone readily available, though that is a great idea, and I have considered a hand ream from McMaster. I need to measure for sure, but the bushings seem sized for the 7/8 shaft that came with the rockers. I would be a bit worried that reaming would open up the tolerance too much and end up with an oiling issue. Do you guys have a source for replacment bushings if I need to start over? I cant seem to find anything.

Here is a picture for anyone curious. You can see the lay I'm talking about if you zoom in on the bushing.
20230201_190740.jpg
 
ch1ll said:
Not looking for an argument, but I disagree with using a hone or any other abrasive tool to size a bearing. Bearing material is too soft and will get imbedded with abrasive leading to wear.
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How do you fit pin bushings?

The number one killer of rocker shaft bushings is not enough oil pump.

If you are running bushed rockers or plain rockers (alumimum or even ductile iron) you need to get the oil volume and pressure up at low engine speeds.

Its also better for the cam bearings.
 
JedIEG said:
Thanks for the suggestions. I'm dont have a rod hone readily available, though that is a great idea, and I have considered a hand ream from McMaster. I need to measure for sure, but the bushings seem sized for the 7/8 shaft that came with the rockers. I would be a bit worried that reaming would open up the tolerance too much and end up with an oiling issue. Do you guys have a source for replacment bushings if I need to start over? I cant seem to find anything.

Here is a picture for anyone curious. You can see the lay I'm talking about if you zoom in on the bushing.
View attachment 1716043033
Click to expand...

See post 7 and send it.
 
JedIEG said:
I bought a set of Speedmaster stainless rockers during the black Friday sale. I knew they weren't going to be perfect OoTB (swarf, deburring etc.) but the bushings have me a little concerned. I can clearly feel, with my fingernail, the machine turning lay on the ID of bushing. This is the first set of rockers I have dealt with at this price point so I dont have a good reference. I have run my finger over a couple of other parts with bushings I have on hand and they dont have nearly the roughness of these rockers so that has me second guessing the reliability.

Any experience with this or if I am worried about nothing? Any ideas where to get replacement bushings if needed? (I would prefer switching to a full width bushing instead of the two piece bushing they come stock with if I needed to replace them)
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Those machining grooves will hold oil. You can run a rabbit turd hone through to knock the high spots off, or a piece of scotchbrite in a slotted rod in a drill.
 
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892AA14C-DDCA-4945-BDD5-DD40661170F0.png


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This is the reamer I would use and take your pick of the bearings. Remember to ream out .0002 per pass till you get the fit you want keeping an eye on surface finish. A cutting fluid would help.
 
If I was building a serious engine where everything needed to be perfect I wouldn't start with Speedmaster rockers. Just sayin.
 
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I'd just polish the bushings up with some fine emery cloth.
 
IMO It's better with two bushings, the center serves as an oil well.
 
a bushed rod has to be honed for proper fit, on pins, done many of those, had no problems , i wash them afterwards, any after market rod pin bores have to be honed for clearance.
 
ch1ll said:
View attachment 1716043065

View attachment 1716043066

View attachment 1716043066


This is the reamer I would use and take your pick of the bearings. Remember to ream out .0002 per pass till you get the fit you want keeping an eye on surface finish. A cutting fluid would help.
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I don't think I'd be using Oilite bushings for rocker arms or anything in a car engine. They are designed for use where there is scant oil supply like electrical motor bearings and other light duty applications, and are a honeycomb structure that retains oil. I don't think they will support the load pressure that a true bearing bronze will either. For any bushing/bearing in a car engine I would be using 660 bronze or 952. That's whats used in punch press crank bearings and it can take a beating. The oil film is what should be taking the load anyway, so making sure the rocker is getting enough oil to the right place is where the effort should be made.
 
gzig5 said:
I don't think I'd be using Oilite bushings for rocker arms or anything in a car engine. They are designed for use where there is scant oil supply like electrical motor bearings and other light duty applications, and are a honeycomb structure that retains oil. I don't think they will support the load pressure that a true bearing bronze will either. For any bushing/bearing in a car engine I would be using 660 bronze or 952. That's whats used in punch press crank bearings and it can take a beating. The oil film is what should be taking the load anyway, so making sure the rocker is getting enough oil to the right place is where the effort should be made.
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That may be, but there are other bearings listed there. If they are suitable or not, I don’t know. I would ask a auto machinist for a recommendation, specific use has to be out there. I just listed 2 sources I know of that supply bearings to industry.
 
ch1ll said:
That may be, but there are other bearings listed there. If they are suitable or not, I don’t know. I would ask a auto machinist for a recommendation, specific use has to be out there. I just listed 2 sources I know of that supply bearings to industry.
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That’s what I already said.

He needs to stop fussing with it and send it. You don’t use oilite for bushing like that.

If the OP is losing sleep over it he can buy a dingle berry hone and slide that in there a few times, wash it them out and go.

Ive been honing bushing for years and years. It’s standard practice.
 
Exactly. Clearance it any way you like. There is no special oil requirement; the the factory oiling system is fine. Think of pistons with floating pins, they rely on splash oiling...& survive just fine.
 
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