Advice on a non-rotating pushrod

[clevtrev]

I have never seen a quill with any "thread" on it at all, if you read Richardson it states that there may be signs of "rubbing" on the quill but this is just bedding in and is of no consequence. I not know that yamaha
had many problems with racers ( apart from Ducatis!" they always seemed to go pretty quick!.) Velo's also have a quill, another design by Mr Irving and these were always pretty good.
dave gs.( Living in the world of shaft drive)

The thread is 1/4" BSW truncated to give the effect you see. So you have never looked at a quill ?

 

[piggywig]

Big-end quill

Dave gs,
Attached one original well worn quill but still showing "threaded" portion, still serviceable but now consigned to the growing old parts box, as nothing gets thrown away, ever!
If the thumbnail and inexpert photography does not show detail it will be posted later in misc. photos.

Col

 

[Tom Gaynor]

Quills

The one that came with my bike, probably the original therefore 43,000 miles old, had a shallow "thread" machined along most of its length.
The reference to Yamaha was intended to be ironic - I used to race a TR3 and later a TZ 350, rocketships, both.

I have never seen a quill with any "thread" on it at all, if you read Richardson it states that there may be signs of "rubbing" on the quill but this is just bedding in and is of no consequence. I not know that yamaha
had many problems with racers ( apart from Ducatis!" they always seemed to go pretty quick!.) Velo's also have a quill, another design by Mr Irving and these were always pretty good.
dave gs.( Living in the world of shaft drive)

 

[rwhitne2]

Phil - thanks for this post. Being new to Vincents this was v. helpful to me w/ my own stuck pushrod. Gave me confidence to tackle it etc. No choice really anyway here in Maine, USA.

Stuart,
I've seen this a couple of times. In both instances, the pushrod was siezed in the cup of the cam follower. These were engines that were rebuilt over 10 years ago and seemed to be using new push rods and/or followers. Attention must be paid to the shape and finish of the cup. I've seen followers that were deficient in both respects.

In both cases, I was able to rectify the problem by lapping in the pushrod. Using fine valve grinding paste, and the rod held in a hand drill, I achieved a polished surface in the cup, and clearance all around. Problem solved. Obviously you need to remove the timing cover, staedy plate, and cam to extract the follower. Ergo refitting is easy.

It is always best to remove the timing cover when refitting push rods. Then you can poke about and be sure they've landed in the cups. Failing that, remove all the valve caps and shine a light down another pushrod tube. You can then see the exact location of the target cup. This will improve your odds and give you a chance of dropping the pushrod home. Again, use the pen light to verify as best as possible. Good luck!

Phil

 

[rwhitne2]

tom - spot on - I had an "accident" also and my pushrods look just like yours, the engine having been rebuilt in '72 and who knows what since (tho the same owner til 2003. Mike Whitney

It's possible the reason the originals weren't replaced is that they were work-hardening stainless steel, and the only ones now available are flame-hardened silver steel. Which is best is arguable, but I like the stainless ones: initially they are soft, but as they wear to shape they harden. Maybe your engine builder thought that too. I was obliged to replace one of mine after "an accident" in which it was bent, so I decided to replace all four - which is the only reason I know this.
Cheer up: if they are silver steel, at least they can be fished with a magnet if one drops in.........
I'd take the timing cover off so I could see what was going on, despite the temptation to use the Mole wrench idea as a quick fix. I suspect you're not the first person to have this problem: 80% of my "new looking but old" pushrods have curious vertical scars on them, just where a Mole wrench would clamp. Probably just coincidence.......

 

[BlackLightning998]

Worth checking something else......

Phil - thanks for this post. Being new to Vincents this was v. helpful to me w/ my own stuck pushrod. Gave me confidence to tackle it etc. No choice really anyway here in Maine, USA.
Phil

Mike,

Mine was the original posting on pushrods and experience and the passage of time now shows that the stuck pushrod was just a symptom of a bigger problem that you might like to check for.

I was offered two clear schools of experience and thought - the, "pull it out, polish it, re-fit it ride and forget" school and then the "take the pipes off, take the timing chest cover off and have a look at what is going on inside" school.

I chose the former advice, my choice. I then found out a couple of thousand miles later that the cams and followers were eating each other for some reason - horrendous wear (have a search on the forum and you'll see pictures) and that the followers were getting hot which has caused the pushrod cup to overheat, distort and trap the pushrod.

Wouldn't have stopped it happening, but I would have found the damage 2000 miles earlier - I've learnt the hard way - next time I'll investigate to find out why the pushrod got stuck!

Might be worth having a look yourself?

Regards

 

[lindie]

i'm of the rip apart school too on most cases stuart. a gasket is usually cheap in comparison to hidden nasties.

 

[rwhitne2]

Stuart - thanks - I have been looking at same and all appears okay. My original problem was that I dropped a push rod while changing the seals and it got badly stuck - not as simple as it seemed for this old Triumph guy. Still learning at age 72 . Really appreciate the VOC - the best group of motor enthusiasts I have ever been in and thats about 11. MikeQUOTE=BlackLightning998;10932]Mike,

Mine was the original posting on pushrods and experience and the passage of time now shows that the stuck pushrod was just a symptom of a bigger problem that you might like to check for.

I was offered two clear schools of experience and thought - the, "pull it out, polish it, re-fit it ride and forget" school and then the "take the pipes off, take the timing chest cover off and have a look at what is going on inside" school.

I chose the former advice, my choice. I then found out a couple of thousand miles later that the cams and followers were eating each other for some reason - horrendous wear (have a search on the forum and you'll see pictures) and that the followers were getting hot which has caused the pushrod cup to overheat, distort and trap the pushrod.

Wouldn't have stopped it happening, but I would have found the damage 2000 miles earlier - I've learnt the hard way - next time I'll investigate to find out why the pushrod got stuck!

Might be worth having a look yourself?

Regards[/QUOTE]

 

[roy the mechanic]

It has been my experience that your motor is talking to you-it's asking for help! if you take the "easy route " it generally means it is about to bite your wallet. If in doubt-check it out, the worst that can happen is you will learn more about the machinery that works so hard to haul your sorry ass down the road.

 

[vince998]

It has been my experience that your motor is talking to you-it's asking for help! if you take the "easy route " it generally means it is about to bite your wallet. If in doubt-check it out, the worst that can happen is you will learn more about the machinery that works so hard to haul your sorry ass down the road.

Anything under 50 MPH and i think it´s screaming at me!!
I don´t listen to the voices anymore
Primary and timing cover off once a year just to check. (i must know the machinery better than my missus by now)

I read 30 years of MPH in one go once (right at the beginning), and shortly afterwoods the voices started.
I rode aroung with 5 kilos of tools and spares in a rucksack for 5 years !!!

Quote:
"I suspect you're not the first person to have this problem: 80% of my "new looking but old" pushrods have curious vertical scars on them, just where a Mole wrench would clamp. Probably just coincidence......."


Funny thing this Tom, but i´ve got a box full of them as well!!, I thought these where caused rotating an engine with un-seated push rods (i.e out of the bottom cup)?