PDA

View Full Version : TR2/3/3A Valve Adjustment?



karls59tr
02-08-2019, 12:58 PM
How often should the valves be adjusted on a TR3? How can you tell when they need adjustment? Should they be adjusted warm? Any other valve adjustment tips?

CJD
02-08-2019, 01:03 PM
Funny...GM and Ford always said to adjust hot...but Triumph gives the cold adjust numbers. So set them cold.

If they start to make a lot of noise (chattering or one valve clicking above the others)...then it's time.

If you spend a lot of time at highway speeds using unleaded gas...check about every oil change.

If you have an old rocker shaft and arms, then a feeler gage will not give an accurate gap. It bridges any wear marks on the arm tips, giving a larger actual gap than measured. Use a dial indicator for worn shafts and arms to get true gap.

I make it a habit to check valves at every oil change, although that's probably overkill.

TR3driver
02-08-2019, 01:47 PM
The TR4 workshop manual says to run the valves every 6000 miles, but I've never done it that often unless there is a problem. Normally, the clearances will only change very slowly as long as the oil is kept clean and so on. So I only do it once a year, as part of what I think of as a "major tune-up".

In addition to excess noise as John mentioned, poor idle quality is another symptom of incorrect valve lash (particularly if they are too tight as a result of valve seat recession). Not getting a clear peak when adjusting mixture is another symptom.

STeve 1958
02-08-2019, 07:33 PM
Pull all the spark plugs and gap them while you can still find your feeler gauge. This makes the engine easy to turn by hand. Then use the rule of nine.
I bought a feeler gauge and when I got home I found it had a .009 and a.011 but no .010. I just used .011 and kept them a little tight.

Steve

DavidApp
02-08-2019, 09:47 PM
When I started to run my engine I had a valve tick. Checked the clearances again and it still ticks. So I removed the valve cover and ran the engine and put pressure an the rockers in turn till I found the culprit. I did noticed that I was getting oil to the rockers.
The ticking rocker was not lose in fact it seemed a little tight so I slackened the adjuster right off to check for wear on the end of the rocker. No wear but the bushing was worn allowing the rocker to move up and down on the shaft.

Have to order new bushes and shaft. I do have a spare that I am cleaning up to see if that can be pressed into service.

I suppose the morale of the story is a ticking valve may not have too much clearance but have a worn rocker bush.

David

poolboy
02-09-2019, 11:23 AM
Or an bad spark plug wire...I adjusted and checked (obsessively) valve lash even swapped rocker assemblies trying to eliminate a louder than normal tick on 'tick over'.
Gave up...but much later for some other purpose I checked wire resistance..I found a bad one, replaced it and then the ticking sounded normal again.

DavidApp
02-09-2019, 01:21 PM
Good point worth remembering.

David

6TTR3A
02-09-2019, 04:33 PM
I just modified the feeler gauge to compensate for rocker arm wear at the
valve stem contact point.

TR3driver
02-09-2019, 06:01 PM
You can actually buy feeler gauges with narrow tips, for that reason.

Personally, I prefer to have the rockers rebuilt when they get that worn. It's easy to remove the shaft, and there is a service out here that does them. I don't recall the numbers offhand, but the total cost with shipping was very comparable to what I would spend for just the parts to do it. The results came back looking like new, I still don't know if they actually replaced the arms or just gave them a flash coat of copper. But only the pedestals and caps were obviously original.

They've moved up north, but originally they were located in the same city where I worked.
https://www.rockerarms.com/

DavidApp
02-09-2019, 09:31 PM
Started to clean up the spare rocker assembly.

The rockers look like they are bronze bit the tip is steel? I need to check them with a magnet. No wear on them.

David

TR3driver
02-09-2019, 09:46 PM
The workshop manual says case hardened steel.

DavidApp
02-11-2019, 11:49 PM
Got the spare one cleaned up and checked that the oil passage was clear to all the rockers. No play on the rockers so I swapper the rocker assembly out with the one on the car. Took the opportunity to re-torque the head bolts.

Set the gaps to 0.010" inlet and 0.012 exhaust as the book says. Or has that been updated?

Still get some ticking. Maybe that is the normal amount on these motors.

David

TR3driver
02-12-2019, 12:50 AM
Unless you have a TR2 or early TR3 with cast iron rocker pedestals; the exhausts should be set to .010".

But .012" won't hurt anything, except a little more noise.

And yes, they always make some valve noise. The curse of solid lifters.

DavidApp
02-12-2019, 10:37 AM
Hello Randall

I thought I remembered they were both 0.010" but could not find the info in a quick leaf through my books so I went with 0.012" to be safe. I well re set later this morning.

The noise sounds more even now. Before there was a definite location for the louder noise.

David

TR3driver
02-12-2019, 02:45 PM
My apologies, misremembered the change point. The aluminum pedestals were introduced to production at TS12564E, which isn't even TR2, let alone an early one! My earlier engine must have been retro-fitted at some point.

Anyway, the .010" number can be found in the back of the factory workshop manual (Engine section of the TR3 supplement), or in Practical Hints (page 31 in the 6th edition)
https://drive.google.com/open?id=0B2H2NJt34OffNjQ4MTkyNjItZTVmYi00M2U2LWJhY WUtMjEyZDgxMzUyNzUw

karls59tr
02-14-2019, 11:20 AM
Can the tip of the rocker arms not be lightly cleaned up with a fine file provided the wear is not excessive?

bobhustead
02-14-2019, 05:01 PM
Karls59

You would have a hard time getting the flatness (parallel to the shaft) and the roundness (perpendicular) right.

Bob

DavidApp
02-14-2019, 07:57 PM
A file will probable not make any impression on them. The tips are very hard.

A machine shop with a flat grinding wheel would be able to do it.

David