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TR6 TR6 rocker assembly questions

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ichthos

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I was having problems with acceleration after putting in a rebuilt head, carbs, and rocker assembly. I am convinced it has to do with the rocker assembly and valve clearances. I coated the rocker assembly lightly with oil initially. I adjusted the valves, went about four miles, and quickly had problems with acceleration. I let the engine cool overnight, and again had to adjust the valves. The rocker assembly looks dry to me. Some of the rockers seem to stick. Shouldn't there be oil coming out of each hole in all rockers? It looks like there is little or no oil coming from the top holes in most of the rockers - especially those in the center. Could my rocker shaft be defective? If it makes difference, I am the one that put the rocker assembley together. Any help would greatly be appreciated
Kevin
 
Kevin,
The oil to the rocker assembly is low volume and pressure, it sort of weeps out. But it is unusual that the center is starved. Your rockers should not be binding.

Can you take of picture of the rocker assembly so we can eyeball how you assembled it?
 
Here is a pic of the rocker assembly itself.
 

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And here is a close up showing how dry it is. I can actually hear the valves go out of adjustment after a couple of miles. When this happens the oil pressure goes down too to about 25.
 

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That does look pretty dry. Might be worth pulling the assembly apart, make sure the bore is clear and the holes are lined up.

OTOH, I had a TR3 that had been assembled wrong, so the rocker shaft got no oil at all. The pushrods were literally rusty! But it ran pretty good that way, for several thousand miles at least (I bought it near Houston & drove it home to LA).
 
seems like the OP would go up a bit if it stopped feeding the rockers. Maybe the low OP is the real problem.
 
Did you have your head shaved ?
as I noticed that the adjusters were showing quite a bit of thread above the locking nut
 
Thought about the OP also, but before the valves move it stays between 50 and 70. Also, before I burned the valve, the oil pressure was fine. I am going to take the rocker assembly apart and see if anything is blocked as suggested. How is it possible to put the rocker shaft in wrong? How do you know if you have put it together correctly?
 
On the rear most pedestal, there is a hole on the passenger side . Line that hole up with the hole in the rocker shaft and insert the philips head screw to keep the shaft lined up so the oil holes are oriented correctly.
 
You said you installed a rebuilt rocker assembly ... generally the shaft is replaced during a rebuild and the replacement may not have been drilled correctly.

If I recall correctly, the TR6 shaft has plugs in the ends that can sometimes get dislodged as well.

I don't see any way that oiling to the shaft (or lack thereof) could cause that kind of pressure drop. Sounds to me more like something is too tight, and binding when it gets hot (like maybe the exhaust valve stems binding in the guides). The OP is also dropping from the heat (thinning the oil plus too much clearance somewhere).
 
TR3driver said:
The OP is also dropping from the heat (thinning the oil plus too much clearance somewhere).
Click to expand...

Gotta go with that one, Randall.
 
To answer a few of your questions, I did not have the head shaved, but who knows what they did before I got this car. I have only owned it four years. I must have not been clear with my wording. I installed a new rocker shaft and new rockers. The old ones were definitely too worn. I hope you are wrong on the valves sticking. The guy who did them was a jerk and wrote "Won't last 1,00O miles" on my receipt which I didn't notice until I got home. He was mad because I took forum members advice over his in not spending $1,000 to rebuild the head. Needless to say he won't help me out if it was his screw up. What can I do if they are sticking? How would I know? I will take the rocker assembly apart and check Poolboys advice to be oriented correctly. I sure hope that works, because I admit I am totally frustrated with this car right now.
 
Nothing in the rocker/valve gear could cause the low oil pressure you are experiencing. That's ok pressure at hot idle but it's low if you've got any kind of rpm on.
I think the real issue is bearing wear on the mains and rods although it could be defective oil pump or even the pressure relief thingie. The low oil pressure could be the reason you don't see much oil at the top end.
Putting in new bearings with the motor in-situ is not particularly difficult providing the journals haven't been damaged, you can get a lot of help on the forum here because lots of us have done the bearings; it makes a "huge" difference in the oil pressure.
I guess start by fixing the rocker assembly and work from there, I suspect you have more than one problem to fix.
 
Wait a minute! What did the guy do now? Did the valves? Wanted $1,000 to do a head job? I thought you said it was a rebuilt head. I'm confused
 
Sorry for the confusion. Let me try and clarify. I took my head in last summer to a local guy that works on British cars. I took my head in because I had a burnt exhaust valve that I could see without even taking the valves apart. When he took all the valves apart, it was obvious they were far enough gone that regrounding out of the question. I don't remember all that I had done, but I did get new valves and springs put in as well as surfacing the head.
 
So, why in the world would he fail to warrant it?
Now, when I did Brit cars in the shops, some of them you knew would be back again for more, but a thousand miles on a head job?

Another thing to look at, rockers off, spark plugs out, crank it and see if you actually get oil of the port in the head under the stand.
Who knows what might be blocking...

If the guides were usable, new valves HAD to cut the seats and grind to match......should be okay.
 
Well, more bad news. I took off the rocker assembly and 7 out of 14 rockers are basically frozen now. I know why the rockers felt like they were sticking when I tried to adjust them now. I have included a picture of the shaft below showing some of the damage. I cut the shaft in a number of places so that I could get what I could off of it without harming the good pieces. Could this be the result of no oil after only about 12 miles total? I have a used rocker assembly off of another TR6 engine (only a few serial numbers away from mine) to compare everything to, and I did assemble everything correctly. I have had enough tonight, but I will check to see that oil is coming out of the ports under the pedastals in the morning. If that works, I am going to put the used assembly on and make sure oil is moving through the individual rockers after I adjust the valves and see what happens.
 

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No matter what you do with that shaft and replacing it is the only thing to do, along with the rockers, you still have to make sure you are getting oil up through the head or this will happen again.
 
Ouch! IMO something worse than just lack of oil was going on there. Shaft too soft, rocker bushings too tight, something like that. And it happened in just 12 miles?! Just the assembly lube should have worked for 12 miles.

I would pull the plugs, and spin it with the starter (rockers still off) until the oil pressure comes up and you get flow from the hole in the head. It can take some time, and the flow won't be very strong, that's OK. But if you don't get oil coming out of the hole, there are deeper problems that you're going to have to fix.
 
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