Rocker Gear

[John McCormack]

I have a set of rocker gear for my TR2 rebuild. Cleaning them up today I noticed two of the rockers don't have oil holes. I've never seen this before and have had problems in the past when a rocker in the TR6 got blocked and destroyed the pin and pushrod.

Any ideas please.

 

[John McCormack]

No ideas were forthcoming, probably because readers were waiting for me to realise my dumb mistake.

On the two rockers in question, there is a hole underneath that directs oil onto the ball pin and pushrod.

I looked underneath but only for a hole opposite the one on top.

Dóh.

[Lebro]

Not so dumb.  I would have expected all rockers to be the same (except left hand & right hand of course)

Perhaps you have a mix & match of rockers from different sources.

Bob.

[John McCormack]

3 minutes ago, Lebro said:

Not so dumb.  I would have expected all rockers to be the same (except left hand & right hand of course)

Perhaps you have a mix & match of rockers from different sources.

Bob.

I'd say they have come from different sources. These rockers were on the head of my daily driver TR2 when I bought it so I knew they were OK. I just didn't look for a hole in an unusual place.

[RogerH]

Hi John,

        I believe the hole in the top is to allow a good spray of oil under the rocker cover to lubricate anything it touches.

The rocker arm it self should be well lubricated as oil is squeezed between the arm bearing and the rod shaft.

You have 6 other fountains - I wouldn't panic.

 

On your TR6 was it the blocking of the hole that did the damage OR did the hole get blocked due to the damage.

 

if in doubt drill a hole where it should be.

 

Roger

[John McCormack]

4 minutes ago, RogerH said:

Hi John,

        I believe the hole in the top is to allow a good spray of oil under the rocker cover to lubricate anything it touches.

The rocker arm it self should be well lubricated as oil is squeezed between the arm bearing and the rod shaft.

You have 6 other fountains - I wouldn't panic.

 

On your TR6 was it the blocking of the hole that did the damage OR did the hole get blocked due to the damage.

 

if in doubt drill a hole where it should be.

 

Roger

On the TR6 it was blocking of the hole due to dirty oil. When I bought the 6 it had done about 5000kms in the previous 22 years, and not many in the years before I got it. I changed the oil and filter and then did it again a few hundred miles later. Sometime after that I got the first blocked rocker and not realising what it was just adjusted the tappets without too much thought. When the noise returned the rocker and pushrod were severely damaged. The rocker was bone dry, not a skerrick of oil on it.

I replaced the ball pin and pushrod, cleared the others and put an oil treatment through the engine. 3-6 months or so later another one went but I picked it up before any significant damage.

I then removed the sump and cleaned the gunge out, new oil and filter, cleaned all the rockers and the shaft. No problems since. The rockers need the oil feed from the hole, especially on the exhaust valves. If it is blocked the ball pin and pushrod will give up.

However, with the TR2 rockers in the photo there is a hole underneath that releases oil next to the ball pin, nearer the shaft than the hole on top is. I just didn't see it.

[roger murray-evans]

John,

Miniscule observation is that your rocker pedestals are TR3 onwards I think,

being aluminium.TR2s had cast iron pedestals hence the differing exhaust valve settings

of TR2 .012/TR3 .010!! (probably makes not the slightest difference either!)

Roger M-E

[Drewmotty]

Rightly or wrongly I welded up the holes in my rockers 35 years ago in an attempt to force the oil to exit through the bearings after the rocker shaft wore out twice in quick succession.

The shaft is still fine and there is always plenty of oil getting splashed around the rocker cover.

[Ian Vincent]

5 hours ago, Drewmotty said:

Rightly or wrongly I welded up the holes in my rockers 35 years ago in an attempt to force the oil to exit through the bearings after the rocker shaft wore out twice in quick succession.

The shaft is still fine and there is always plenty of oil getting splashed around the rocker cover.

Back in the day when we ran cars on a shoestring, I did the same by drilling and tapping so that I could insert a small set screw in each rocker to deal with a worn rocker shaft.  It was on a Healey 3000 and it worked for as long as I had the car.  It marginally boosted the oil pressure and reduced the amount of oil splashing around the rocker cover whilst forcing the lubrication out through the bearings.

Rgds Ian

[John McCormack]

On 2/27/2019 at 10:06 PM, roger murray-evans said:

John,

Miniscule observation is that your rocker pedestals are TR3 onwards I think,

being aluminium.TR2s had cast iron pedestals hence the differing exhaust valve settings

of TR2 .012/TR3 .010!! (probably makes not the slightest difference either!)

Roger M-E

Yes Roger. This one is from a high port head that was on my daily driver when I bought it. The head was heavily modified and the car went very well. The head swallowed a valve up through the valve seat at 110mph on the freeway 25 years ago.

 Apart from the clearances they are fully interchangeable. If I find a steel pedestal one I'll get it but in terms of originality it  isn't visible and has exactly the same function.