Jump to content
Sign in to follow this  
oldtuckunder

Triumph Rocker oil Holes

Recommended Posts

 
 
 
Just posting this from a PM thread as it may be of general interest, and others may also have insight/comments
Alan

Hi John

Just playing with rockers and had a question you may be able to answer.  The standard Triumph rockers have a hole drilled between the rocker arm and the journal that runs on the shaft, so that a little dribble of oil is fed to the rocker tip to I guess 1) Lubricate the tip to valve stem contact, and I guess also apply a dribble of lubrication to the spring assy and the the valve stem. Looking at other cast rockers like mini ones they don't seem to have this feature. I think I picked up that you are now using roller rocker arms? do they have a feed from the bushing to the tip/roller assy? or do they rely on way more oil being fed to the whole rocker box area to compensate.

Alan

Alan,

That oil feed to the rocker journal is all there is.    No further drilling out to the tip, which is - must be! - lubricated by splash.

I belive that there are some roller rockers that  provide an oil passage, but in this example, it just catches splash i the open top and allows it to seep down onto the roller, which is otherwise covered.

Related image

http://www.jegs.com/p/COMP-Cams/Comp-Cams-Ultra-Gold-ARC-Aluminum-Rocker-Arms/955190/10002/-1

My rollers are Titans, that also shroud the roller, but AFAIK they rely on splash.

 

  4 hours ago, JohnD said:

That oil feed to the rocker journal is all there is.    No further drilling out to the tip, which is - must be! - lubricated by splash.

Interesting! I'm tempted to say what splash with the standard triumph oil feed to the rocker shaft, which in my experience is just a nice positive dribble sufficient to do the job, unless an external oil feed is added when yes the rocker chamber does seem to get flooded.

The tip feed in the Triumph Rocker is interesting in that I haven't seen it in other common engine rockers like Mini, Ford, MG I wonder if they all had higher oil feed volumes to the rocker assy?

Alan

"tip feed"?    Do the ones I sent you, or the ones yu have fitted, have a drilling out to the tip?

I've had a look at Mini sites, and they rely on splash, the originals anyway.

This video of a very similar Ford arrangement shows a small drilling in the rocker hub, that leaks oil onto the side of the rocker arm, in the hope that it will splash out onto the valve stem , I think.  On the evidence of that film, and the oil sitting on the spring caps, it works, mostly, but not on No.3 valve (from the right)!   And a massive flow of oil out of the rocker beraings and dow the floor of the gallery.   

 

Is that what you mean?    I don't think Triumph's have those, do they?

JOhn

 

Wow what a strange world we live in. Its not what you know that is dangerous its what you think you know.

I was always certain that from the MK1 Vitesse onwards all the Triumph engines used the same rockers, and I'm right but wrong.

So I popped out the garage to take a picture of your rocker shaft with the feed holes in the rockers, and as you see below it doesn't have any!

5a9187176aec9_rockertipfeed001.thumb.jpg.3cf4642916251737956f79bcd41b3ade.jpg

So dug out a Spitfire 1500 one and as below it does, almost similar to mine except on mine the hole is about 10mm further towards the tip

5a91887aebb22_rockertipfeed002.thumb.jpg.bf68718ceff92f609e9795bf4c57882a.jpg

So a quick check on Rimmers shows that yes I was correct all the engines used the same rockers, and their picture shows one with a feed hole.

https://rimmerbros.com/Item--i-109023

So as mine is an early engine and the Spitfire 1500 is a late one, and I guess yours is middle period, all I can assume is that they used to make them with feed holes, then they stopped (reduced cost?) and then they started using them again (maybe because of problems).  Or the rockers on your shaft come from a non OE source that didn't drill them, but they look genuine.

I can understand why they may have moved the hole back a bit between mine and the 1500, easier drilling and maybe slightly stronger.

However I can say I like the idea of that feed hole as it does encourage lubrication to run down to that rocker tip.  

Wish I'd started this as a thread rather than PM to see what others know, however I thought it was a simple question if they did the same thing on the roller rockers?

Alan

 

 

 

 

 

As I know from my frequent urgent conference calls to Sideways, just talking about a problem frees it up!    Either it starts new ideas in your mind or you get new information from others.   See my posts this PM about Trigger Wheels to prove it!

Your researches have revealed a facet - a hole! - in our knowledge of Triumph rockers.   I'm sure you could just copy and paste this thread into one on the general board, and I'd say do it, to publish this newly discovered fact.

AS to why the holes were there at first then not, then back again, I'm sure that it was production managment accountants - or just Sir John Black, the old skinflint, who was always keen not to spend money.

John

Share this post


Link to post
Share on other sites

Yep, some rockers have holes on top, some don't.  Not sure what the pattern of distribution is though.  I've a feeling I've seen them with hole below too, close to the adjuster ball, though I couldn't swear they were Triumph ones......

There's plenty of fine oil drops flying around in there at higher rpm anyway - it's prolonged idle that kills 'em I reckon.  Thrash'em, they love it!

Nick

 

Share this post


Link to post
Share on other sites
1 hour ago, Nick Jones said:

There's plenty of fine oil drops flying around in there at higher rpm anyway - it's prolonged idle that kills 'em I reckon.  Thrash'em, they love it!

 

Never had the cap or rocker cover off at high rpm's to see, however I'm not so sure how much is flying around in there with the standard triumph feed.  Its hardly scientific but if I take the rocker cover off during the season for an odd tappet check, I find the rocker shaft, rockers, springs, and head surfaces have a very nice thin oil film covering, but the inside of my rocker cover is almost dry. Now I run very very clean oil with a couple of changes during the season so I don't have any black stuff around to leave tell tale marks on the inside of the cover, and it could be that a very fine mist of clean oil has just run off the inside of my cover. If I take the cap off with the engine running (all be it at lower revs) I can see a nice pulse dribble coming out of the oil hole on the visible rockers, which is a nice visual check that there is oil getting to the rocker assembly, and yes I can see why on assemblies without oil holes prolonged idle wouldn't be good as what little oil does get pumped up to the rocker shaft is going to lubricate the rocker bushes and then just drop on to the cylinder head without much opportunity to be flung around to lubricate the rocker tip and valve stems.

Think if I was building a rocker shaft with factory rockers I'd make sure they were the ones with oil holes, and as they are identical rockers across the whole range it does mean you can raid a few spitfires for them :biggrin: Would be interesting to know if all the new ones supplied by the likes of Rimmer's have holes in them, and also if their uprated ones with bronze bushings also have a hole, and if so is it drilled through the bronze bush.

Alan

Share this post


Link to post
Share on other sites

I'm judging by the amount of oil that is carried through the breather if you have a blow-by issue.  The PI used puke pints out that way into the air box, even after the external feed was removed.

I've seen some stories about the "uprated" rockers with the bronze bushes.  The bushes are a fine idea, but possibly covering for the rockers themselves not being sufficiently hard.  Rapid wear of the tips has been reported and the occasional outright breakage......

Nick

Share this post


Link to post
Share on other sites

I noticed this when I was trying to work out why I had a loud tap from the engine on first start up. You all identified it as lack of lubrication to the rockers which turned out to be a blockage in an oil gallery in the recon head. These where a selection of Rockers known to come from Mk2 vitesse early and late 1970 and a 2.5 tc and PI.

Mark

Edited by Mark

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×