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Rocker Shaft & Valves


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Evening All, or morning to some.

Spent the last two days confirming TDC and setting all the 12 valve clearances. Haven`t a clue exactly what cam I have except its a fast road cam and stage 2 conversion to bring a US 125bhp version up to a UK 150 PI. Thralled through the web and online and come to the conclusion to set inlet to 0.014" and exhaust to 0.018" as a compromise from available data.Sounds OK and seems to run OK at idle as well as further up the rev range. Anyone know how to find out what cam I have while I have the cover off without too much dismantling?

Second questions are:

1. At idle with the cover off, all rockers are "oiling" through the small hole in the rocker, except for No 11 where no oil is emerging. Is this a worry?

2. At the front end of the rocker shaft (split pin end) there are what look like two rubber washer to fill the gap. At the rear end there is only one leaving a gap of 2 mm. Is this a worry has something broken off?

Cheers Colin. 

 

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14 hours ago, c.hydes said:

Evening All, or morning to some.

Spent the last two days confirming TDC and setting all the 12 valve clearances. Haven`t a clue exactly what cam I have except its a fast road cam and stage 2 conversion to bring a US 125bhp version up to a UK 150 PI. Thralled through the web and online and come to the conclusion to set inlet to 0.014" and exhaust to 0.018" as a compromise from available data.Sounds OK and seems to run OK at idle as well as further up the rev range. Anyone know how to find out what cam I have while I have the cover off without too much dismantling?

Second questions are:

1. At idle with the cover off, all rockers are "oiling" through the small hole in the rocker, except for No 11 where no oil is emerging. Is this a worry?

2. At the front end of the rocker shaft (split pin end) there are what look like two rubber washer to fill the gap. At the rear end there is only one leaving a gap of 2 mm. Is this a worry has something broken off?

Cheers Colin. 

 

Can't answer the first bit on clearances but the lack of oil on a rocker is a major worry. I have had two such instances early in my TR6 ownership. The first time the pushrod and tappet destroyed themselves. The 2nd time I knew what to look for when I got tappet noise and saved the parts. TR6s are known for it as the oil galleries up there are very small and any small debris in the oil blocks them. The tappet/pushrod dry out and beat themselves to death.

My car hadn't been used regularly for 25 years and I ended up removing the sump and cleaning out the sludge that had built up. Haven't had a problem since in about 2-3 years.

It isn't difficult but it is a bit time consuming to fix. Remove the rocker shaft and then take all the rockers off, one by one, and use compressed air to ensure all the oil ways are clear. Reassemble, refit and set the clearances again. Check the oil is flowing.

I don't recall any rubber washers at the ends of my rocker shaft but they might have been there. The Moss catalogue doesn't show any.

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Maybe you can blow clear via the little hole in the rocker with compressed air. Off course, the debris may come back in this or another rocker.

Waldi

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Thanks everyone for the replies.

I made a mistake about the "rubber washers" at each end, they are in fact spring washer spacers which are correct.

I started it up again yesterday with the rocker cover off, left at idle till up to normal temperature, and again all rockers were oiling themselves except for No. 11. However, if you push the rocker with a screwdriver against the spring towards the front whilst running, oil does then begin to emerge from the oilier hole. Release it back to normal position, wipe off oil and again no flow. 

Am I being overly concerned here, ie with the cover on and higher revs it will all splash everywhere or maybe No. 11 will start to oil properly?

Thanks, Colin.

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15 minutes ago, c.hydes said:

Thanks everyone for the replies.

I made a mistake about the "rubber washers" at each end, they are in fact spring washer spacers which are correct.

I started it up again yesterday with the rocker cover off, left at idle till up to normal temperature, and again all rockers were oiling themselves except for No. 11. However, if you push the rocker with a screwdriver against the spring towards the front whilst running, oil does then begin to emerge from the oilier hole. Release it back to normal position, wipe off oil and again no flow. 

Am I being overly concerned here, ie with the cover on and higher revs it will all splash everywhere or maybe No. 11 will start to oil properly?

Thanks, Colin.

No, it needs the oil from the rocker. Splash won't do it. It will take no time for it to start to disintegrate.

Try taking the rocker shaft off and blowing compressed air through that rocker oil hole. It should clear it but keep an eye on it that it doesn't block again.

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On 5/3/2020 at 9:30 AM, John McCormack said:

Can't answer the first bit on clearances but the lack of oil on a rocker is a major worry. I have had two such instances early in my TR6 ownership. The first time the pushrod and tappet destroyed themselves. The 2nd time I knew what to look for when I got tappet noise and saved the parts. TR6s are known for it as the oil galleries up there are very small and any small debris in the oil blocks them. The tappet/pushrod dry out and beat themselves to death.

My car hadn't been used regularly for 25 years and I ended up removing the sump and cleaning out the sludge that had built up. Haven't had a problem since in about 2-3 years.

It isn't difficult but it is a bit time consuming to fix. Remove the rocker shaft and then take all the rockers off, one by one, and use compressed air to ensure all the oil ways are clear. Reassemble, refit and set the clearances again. Check the oil is flowing.

I don't recall any rubber washers at the ends of my rocker shaft but they might have been there. The Moss catalogue doesn't show any.

Hi Colin,

The oil gallery on the side of the block collects  sludge, when rebuilding an engine it is important that the blanking plugs at each end are removed and a rifle bore type rod and brush are pushed through from end to end, to push out all the sludge and there can be an awful lot !

Bruce.

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John/Waldi: Agreed you did recommend that earlier. I suppose taking off the rocker gear and removing all the parts and giving everything a good clean up isn`t too complicated - correct? Any tips on what to be careful off, or what not to do would be useful. If all the parts don`t show any worries or wear can I just re-assemble and set up correct rocker gaps? Also how do I get the blanking plugs off each end , and will they go back on again without falling out?

Bruce: when you say .........."oil gallery on the side of the block and removal of blanking plugs/clean out", you are not referring to the rocker shaft -correct? If not is this a big strip down, how do you do it?

Thanks and regards, Colin.

 

 

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It is pretty normal, that there are some oil holes preferred

but they should not be blocked. Even with the additional oil line

some rockers stay nearly dry.

 

With the cam I would recommend to check the max lift and lift at TDC

With these data there might be a hint, what is in use.

 

Would not be that problem if there would not be the Kent or Bastuck cam

that requires much more clearance. If you have it and give it 0.01" clearance

the valves might fail and spoil the engine.

 

A coarse hint might be that the Kent is set 5 degrees advance what means

at TDC the inlet valve is more open than the exhaust. All the others I know

have same lift at TDC.

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Colin,

before you dismantle the rocker assy, first increase revs and see if oil starts flowing from #11.

If you still see no oil, I would first blow clear as indicated above, yes, it’s a quick fix.

If you want to remove the entire rocker assy, be carefull to release the pedestals one bit each at a time. Follow the wsm.

I the rockershaft is worn, it is best to buy a new tuft-rided one, not the soft ones. Ensure the end caps are in and the oil hole From the rear pedestal in in-line with the hole in the rocker shaft.

Waldi

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On 5/4/2020 at 4:04 PM, TriumphV8 said:

It is pretty normal, that there are some oil holes preferred

but they should not be blocked. Even with the additional oil line

some rockers stay nearly dry.

 

With the cam I would recommend to check the max lift and lift at TDC

With these data there might be a hint, what is in use.

 

Would not be that problem if there would not be the Kent or Bastuck cam

that requires much more clearance. If you have it and give it 0.01" clearance

the valves might fail and spoil the engine.

 

A coarse hint might be that the Kent is set 5 degrees advance what means

at TDC the inlet valve is more open than the exhaust. All the others I know

have same lift at TDC.

Andreas, thanks for the suggestions on the camshaft etc. I don`t want to confuse this post with the original concerns which is why no oil dribble is coming out of rocker No. 11 hole, but all others are oiling OK. Maybe we can have an offline communication just about camshafts and your advice on how to measure? Would you be happy with that?

Cheers, Colin. 

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On 5/4/2020 at 6:09 PM, Waldi said:

Colin,

before you dismantle the rocker assy, first increase revs and see if oil starts flowing from #11.

If you still see no oil, I would first blow clear as indicated above, yes, it’s a quick fix.

If you want to remove the entire rocker assy, be carefull to release the pedestals one bit each at a time. Follow the wsm.

I the rockershaft is worn, it is best to buy a new tuft-rided one, not the soft ones. Ensure the end caps are in and the oil hole From the rear pedestal in in-line with the hole in the rocker shaft.

Waldi

Thanks Waldi, yes I tried to increase revs above idle, but oil sprayed everywhere! I can`t see how this can be done without the rocker cover on but that defeats the object and would be confusing for looking at the emissions from the rocker No. 11 hole. Any ideas?

I can`t see that the hole in the rocker, nor to the feed to it, is blocked as when pushed off centre against the spring towards the front whilst running, its starts to oil? 

It doesn't make sense does it, so can`t be blocked?

Cheers, Colin.

 

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38 minutes ago, c.hydes said:

Thanks Waldi, yes I tried to increase revs above idle, but oil sprayed everywhere! I can`t see how this can be done without the rocker cover on but that defeats the object and would be confusing for looking at the emissions from the rocker No. 11 hole. Any ideas?

I can`t see that the hole in the rocker, nor to the feed to it, is blocked as when pushed off centre against the spring towards the front whilst running, its starts to oil? 

It doesn't make sense does it, so can`t be blocked?

Cheers, Colin.

 

If on idle you can move the rocker and can see oil on the shaft leave well alone.

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15 hours ago, ntc said:

If on idle you can move the rocker and can see oil on the shaft leave well alone.

Thanks NTC, can you explain your rationale to your comment? Just need to understand the logic here.

Cheers, Colin. 

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Think I understand,  there is oil inside the bearing, although it is not excessive. Friction side (contact) is on bottom.

Waldi

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All well and good If you know what you are doing.

Thanks NTC, can you explain your rationale to your comment? Just need to understand the logic here.

I will but first do you have a external rocker feed fitted?

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15 hours ago, ntc said:

All well and good If you know what you are doing.

Thanks NTC, can you explain your rationale to your comment? Just need to understand the logic here.

I will but first do you have a external rocker feed fitted?

Thanks all, I do not have an external Rocker feed connected.

Colin.

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4 hours ago, c.hydes said:

Thanks all, I do not have an external Rocker feed connected.

Colin.

Sorry forgot to ask do you have a up rated rocker shaft ie can you see a bush on the outside of the rockers

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28 minutes ago, ntc said:

Sorry forgot to ask do you have a up rated rocker shaft ie can you see a bush on the outside of the rockers

Hi NTC, no I don`t think it is uprated. The car is a US (125) converted to PI, stage II, and fast road cam. The rocker shaft has the location screw fitted, as well as two end caps fitted. 2 photos attached.

The rockers dont have a brass insert bush fitted that runs on the shaft. All in all all parts look like the orginal, Mileage is 83,000, oil pressure always good circa 70 psi at idle. As stated, oil emerges from all rockers and then runs down the rocker to the tip and then valves except for No. 11.  

Hope this helps, and thanks Colin.

Front Rockers.JPG

Rear Rockers.JPG

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OK NTC understood, dry all rockers and shaft, block all other rocker holes except No. 11. Run it up on idle and see whether No 11 starts to oil. This will prove that the extra pressure (in the rocker shaft), pushes up to No.11 hole -correct?

Whatever the result, then remove the other 11 blocked rockers and see what happens - correct?

Whatever the results above, if No. 11 rocker has oil emerging from either side and under the rocker then this is OK. But why, surly they should be all the same?

Regards, Colin. 

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Hi

Leave the shaft alone it may only be a small blockage just might force it out. If the oil comes out beside the rocker then oil is getting there also remember hot oil is what you need this you will not see on a cold engine also hot oil will always find the easy way out 

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OK NTC + others thanks, will do this tomorrow and let you the outcome shortly. I do really appreciate all your inputs, fantastic suggestions and keeps me thinking. 

Standby for results, Colin

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4 hours ago, c.hydes said:

OK NTC + others thanks, will do this tomorrow and let you the outcome shortly. I do really appreciate all your inputs, fantastic suggestions and keeps me thinking. 

Standby for results, Colin

I must partly disagree with ntc, oil on the shaft is only part of the need for lubrication of the rockers.

The pushrod and rocker ball pin need oil. The oil seeps down the rocker from the oil hole on the underside of the rocker. The cup on the end of the pushrod should be full of oil. If this runs dry the pushrod and rocker pin beat each other to death. It has happened twice on my TR6 although I saved the parts the 2nd time because I knew what was happening.

 

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