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TR6 TR6 rocker assembly questions

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" I will check to see that oil is coming out of the ports under the pedastals in the morning"

It's not going to come out of but one hole, the one under the rearmost pedistal. From there oil goes thru the rocker shaft to the arms.
 
Kevin, IIRC you replaced the rocker shaft so that is a new one.
If it is where did you get it and is it a hardened one?
 
Kevin, take a look at this picture. Notice upward pointing arrow as it locates the rocker oil feed hole, then compare the downward pointing arrow identifying the worn area on the shaft. This rocker was not properly installed on the shaft. The oil that should have lubricated the rocker, instead went out onto the head, starving the downstream rockers of oil plus reducing the supply to the upstream ones.

TR6rocker3.jpg


Compare your wear pattern to this old shaft where you can see each rocker arm covered the supply hole and oil reservoir.
P8270002_edited.jpg


So here is what happened. A rocker or several, lacking oil, seized on the shaft. One or more kept a valve open, which gave you the "putt-putt" sound.

An expensive mistake, but not a budget buster.

To get you back on the road until you can afford new parts:

Check your old spare rocker assembly for proper alignment of the rockers over the oil supply holes and correct as necessary.

and, check your push rods to insure they are not bent by rolling them on a hard surface.
 
Don, I bought the shaft and rockers from BPNW is all I can tell you. I removed the rocker assembly, push rods, and spark plugs and then turned the engine over. It took about 10 seconds, and then oil came out the feeder hole for the rocker assembly. As far as the shaft goes, the holes and groves do not match up perfectly on the old and new rocker shafts. I have a close up of the last half of the shaft nearest the fire wall and my old shaft. Would this normally be acceptable still? I double checked my work, and I can't see how I could put the rocker shaft together incorrectly since the posidrive screw near the firewall only goes in one way on the last pedistal. Oviously I need a new rocker shaft. Can I use the seven rockers that came off smoothly and just order seven new ones? Two of my push rods are bent, but I have two extras. As a number of you mentioned, I can go no further until I figure out what the real problem is. At this point the problems seems to be me or the rocker shaft. What should I do now?
 

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Here is another picture showing the two pushed up to a square for better comparison. The posidrive scew hole matches up, but the groves and holes do not.
 

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Adjusting the valve lash is often confusing to some, judging from the posts I've seen on the Forums. Do you feel confident that you have it down pat ?
I, too, noticed the extensive amount of threads showing on one of the adjusters in a picture you posted.
 
ichthos said:
Are you asking me to take a close up or better quality picture?
Click to expand...
Yep

poolboy said:
Adjusting the valve lash is often confusing to some, judging from the posts I've seen on the Forums. Do you feel confident that you have it down pat ?
I, too, noticed the extensive amount of threads showing on one of the adjusters in a picture you posted.
Click to expand...

Ken, do you think so much has been shaved the P. rods are too long?
 
I'd sure be suspicious of that Don. That is an awful lot of thread showing if the gap is .010.
 
I think I have done it corectly, but to be honest, I am never totally confident in anthing I do on this car. I have learned a lot over the last few years from reading my my book and forum member help, but I do better with hands on examples - something I don't have available to me. I have adjusted valves on this car before without any problems. I have the Bentley manual, so I followed the sequence shown and adjusted them to .010. I adjust two at a time to .010 and check it with a .009 to make sure it is not too tight and a .011 to make sure it is not too loose. I check my valves twice to make sure. I think the threads may be sticking out because the rockers were already sticking and I didn't realize just how bad they were sticking until I took everything apart.
 
Ken isn't saying that Kevin. He is talking about checking valve lash to see if you need shorter push rods.

I think that is what he is saying
 
But you followed the sequence and were able to tell when the 2 "indicator" valves were open (down) and the 2 you had to adjust were closed (up), right ?
 
DNK said:
Ken isn't saying that Kevin. He is talking about checking valve lash to see if you need shorter push rods.

I think that is what he is saying
Click to expand...
I guess I was kinda beating around the bush on that, Don. I kinda wanted to feel Kevin out on his technique.
I also wonder if he has any adjustment left or is the push rod now directly on the rocker arm. There doesn't look like there's much adjustment screw left to contact the push rods..at least in the picture.
 
ichthos said:
What should I do now?
Click to expand...
First thing you should do is contact BPNW and ask what they will do about the obviously defective rocker assembly they sold you! My choice would be to return it to them for a refund; and send the old, worn one off to Rocker Arm Specialists for rebuilding. Although their web site design is pretty awful, they did great work on my rocker assemblies and the price was very reasonable. Took about 2 weeks from the time I shipped them my old ones until I got the rebuilt ones back, but it probably varies with how busy they are, whether the parts are in stock, etc.

If BPNW won't refund your money, I'd put the old one back on the motor (so I could drive in the meantime) and send the new one to RAS. Be sure to explain to them what happened, so they know not to just copy the defective shaft. Since all of the force on the rockers is in one direction, the engine will actually run quite well with the rockers & shaft badly worn. And they should be able to rebush and/or ream all the rockers to make them right, plus repair or replace anything else that is below par (like the shaft).

As far as the adjusters, I agree they look higher than usual. But as long as the valves are adjusted properly, and the pushrod cups are not hitting the underside of the rocker, they are not "too high". And it might be just that BPNW supplied adjusters that are longer than usual.
 
I didn't see your replies as I was writing mine. I didn't mention this earlier, but I did end up swapping heads from another engine because mine had corrosion from one of the coolant holes into the fire ring area of one of the cylinders. How would I know if it was shaved or not? Is this something I could measure easily? I enlarged the picture. Let me know if it shows what you want.
 

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from your pics it also looks like there are suppose to be horizontal flats machined from the small oil hole to the groove and where the new shaft is worn bad either the flats are worn off or were not there???

Hondo
 
Hondo, you should be able to see the flat parts now. Randall, I doubt that I could get a refund now since I bought the the parts over a year ago. Plus I had to section the shaft with a cut off tool to get the parts off. I normally check my old parts against new, but forgot to this time around to compare shafts when I put it together. I won't make that mistake again. So, are you saying you definetly think the rocker shaft was the problem? What I want to do is put the rocker assembly from my second engine on so that at least I will have transportation. I am a bit on information overload. So here is what I have: Seven of the new rockers look fine inside, and seven are scratched. I also have the original rockers and shaft. Would I be better off to just get a new shaft and seven new rockers, or would I be better off to just send everything from my old rocker in and ask for it to be rebuilt?
 
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