Fixes for loose rocker arm spindles?

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Who has successfully fixed their loose rocker arm spindles?

I have noticed on some of the early 1960's heads I have with scrolled rockers that the fit is much more loose than on later sixties and 1970's heads. Some of them will fall out if the head is tipped sideways and I fear they are a sloppy enough fit that they would move in use and beat their holes oval if they have not already.

Welding and re-machining would leave the area soft and prone to beat out and loosen faster. Steel bushes would get loose at high temp., bushing with hard aluminum might work. JB weld gets weak at high temp and would beat out. Hard-chroming the spindles and honing the rockers to fit is an option.

Just wondering if anyone has ever came up with a fix that stood the test of heat and miles.

Thanks.
 
I have fixed them two ways.
First and probably the best was to make oversized spindles and ream the holes. The rocker then needs to be honed to fit. I have made new spindles from aluminum bronze and found they wear better than steel.

I have also repaired them with thin-walled aluminum bronze bushings. Touchy process. Jim
 
Simillar to what Jim did, I have had Commando spindles hard chromed to a slight oversize, and then honed the rockers to fit. In my case, the fit wasn't so loose as to require reaming the head or making bushings, and not much honing was needed.

Ken
 
Mine weren't loose to the point that they rocked in the head but loose to the point that they slid out with minimal effort.
I found that they would slide into the head past the point that they would disengage the locking tangs in the spindle plates and then rotate as the engine was running causing it to lose alignment with the oil holes.
My fix was to take a center punch and tap 3 spots around the inner boss to raise the metal so that the spindle would have some interferance fit when driven home.
I also went to my hardware store an bought a 2" long stiff spring to the diameter of the inner bosses smallest diameter, cut about 3 coils long of a piece of the spring and fitted it in the bore prior the driving home the spindle.
This would allow the spindle to remain pressed up against the spindle plate and keep the spindle from turning.
This worked the best as it hasn't moved at all since fitting it over a 1000 mile ago.

Now if the bores are just wiped out, then that is another story.
 
I fixed mine with bearing-fit loctite. Make sure you don't get it where it will lock the rocker arm to the spindle!
 
Depending on the amount of wear, a fairly well known engineer in the UK told me that he got a large ball bearing, placed it on/in the head where the roker shaft locates and gives it a sharp tap with a hammer. This spreads the alloy slightly.

I don't suppose it's as good a fix as Jim and Kens, as it will be fairly localised where the alluminium spreads, but another possible way to improve the situation.
 
A cheap and dirty trick if the outer hole is only slightly loose is to use a 1/2 inch grade eight bolt-fully threaded- along with a couple hard washers and a nut. Put it through the outer hole and torque it guten-tight. I squeezes the metal and shrinks the hole a couple thousandths. Jim
 
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