After thinking that I've somehow fixed the ticking noise a number of times and never really knowing why I came across a page that said to rev from idle in neutral slowly to 3000 rpm over 15 secs and then letting it drop back to idle and keeping it there for 15 secs and repeating that cycle (up to 30 times apparently) it'll come good.

Ok I did that a couple of months ago (took about five goes) and it seemed to work.

Started to come back a couple of times since and both times doing the above made the ticking noise go.

way better method you have found ...

than stripping down the top covers off a V6 engine

Yep, good old Mitsubishi last adjuster bleeding technique. Everyone should know about it.

http://s25.postimg.org/w5v4ojkov/lifter_bleeding.jpg

I had my lifters out when doing the valve stem seals, and I cleaned them in diesel yet they still ticked afterwards. Presumably this would not help them?

They've been fairly quiet recently but I did add a can of the LiquiMoly lifter additive.

This process worked for my magna TP (2.6 astronII).
Along with going to semisynth 15W40 from the typical 20W50 (oil for older cars!).

I had my lifters out when doing the valve stem seals, and I cleaned them in diesel yet they still ticked afterwards. Presumably this would not help them?

They've been fairly quiet recently but I did add a can of the LiquiMoly lifter additive.

Yes this process should work. It's because there is air in them which there isn't supposed to. This process opens them up and gets new oil in them. Otherwise if you have them up you're supposed to stand them upside down in a tub of new oil so oil will soak down through the nipple and in to the chamber.

I've seen magnas that have been starved of oil (1l came out at the oil change) and the lifters then go very noisy once you get under a certain level. Lifters were still very noisy for weeks after the starvation occurred. Went through this process and it sounded like new afterwards.

The thing is though, if the lifters can lose oil overnight, then wouldn't it mean this would need to be done each time the car is driven?

I thought the lifters had new oil pumped through them with the engine, as oil squirts into them and they are spring loaded so at the valve closed position they would pull oil in while extending their max limit governed by the valvetrain?

Correct. They are meant to change in length as the engine runs and goes through min to max temperature cycles, in order to keep the rocker to cam lobe clearance constant.
If they seize up, the normal cycle compresses them and they won't come back up to normal length, hence the slight hammering noise.
Clean oil of a low viscosity helps - 15W-40 instead of 20W-50 for instance, as do some additives.

Cleaned mine out as per the manual on a V6 TS, replaced a couple that wouldn't co-operate - still got the cold tick, but went away after warming up. No big deal.

In pondering the sheet posted (in post 2) I checked the oil level more carefully and it's too much. I think when filling last time I discounted the effect of not doing it with the car level. As a result I keep having to do the above procedure about once a week. I feared it was a sign of something terminal, which at 403000 k's wouldn't surprise me. No doubt the lifters could do with a good clean. The whole engine could. It's never been opened up, except to change a cam seal. So, if I start, where do I stop? I figure If I can clean them with some technique like running a bit of ATF in the oil before next change and in the mean time siphon off some oil ... and see how it goes. ?

I thought the ATF in the engine oil was a busted myth?

In pondering the sheet posted (in post 2) I checked the oil level more carefully and it's too much. I think when filling last time I discounted the effect of not doing it with the car level. As a result I keep having to do the above procedure about once a week. I feared it was a sign of something terminal, which at 403000 k's wouldn't surprise me. No doubt the lifters could do with a good clean. The whole engine could. It's never been opened up, except to change a cam seal. So, if I start, where do I stop? I figure If I can clean them with some technique like running a bit of ATF in the oil before next change and in the mean time siphon off some oil ... and see how it goes. ?

Lifters tick because they are either worn and lose oil while parked, or they are gummed up to the point where they are compressed and can't extend back to full length. But on a 403,000 Km car, I wouldn't worry about it, unless the tick stays there when the engine is hot.
I wouldn't add ATF to engine oil, no idea what it would do to seals for example.
Oil level is ok even if 1 cm over full.
Synthetic oil like Mobil 1 may help to clean out the lifters if they are glued up with varnish.

As to 'where do you stop?' Why, looking for a third gen with about a quarter of the km on it, of course!

Thank's for the ideas Max. I've got another TS with 140 000 k's on it waiting to take over when this one finally carks it.

_________________________



Here's a transcript of the page kindly posted in post 2:

BLEEDING THE LASH ADJUSTER SYSTEM

http://i27.photobucket.com/albums/c168/yanndee/bleed_zpsfgvts1yt.jpg

NOTE

- Parking the vehicle on a grade for a long time may leak oil from the lash adjuster causing air to enter the high pressure chamber when starting the engine.

- After being parked for many hours, oil may run out from the oil passage. It takes time before oil is supplied to the lash adjuster, causing air to enter the high pressure chamber.

- In the above cases, eliminate the abnormal noise by bleeding the lash adjusters as follows:

1. Check the engine oil. Add or change oil if required [image Z7EN0207]

NOTE

- If the engine oil level is low, air is sucked from the oil screen, causing air to enter the oil passage.

- If the engine oil level is higher than specification, oil may be stirred by the crankshaft causing oil to be mixed with air.

- If oil is deteriorated, air is not easily separated from the oil, increasing the amount of air contained in the oil.

- If oil mixed with air enters the high pressure chamber inside the lash adjuster from the above causes, air from the high pressure chamber is excessively compressed while the valve is opened, resulting in abnormal noise at closing of the valve. This is the same phenomenon as when the valve clearance has become excessive. The lash adjuster can resume normal function when air that has entered the lash adjuster is removed. [image 7EN0392]

2. Idle the engine for 1 to 3 minutes.

3. Repeat the operation pattern shown at left at no load to check for abnormal noise. [image 7FU2059]

(Typically the abnormal noise ls eliminated after repeating the operation 10 to 30 times. If no change is observed in the abnormal noise after repeating the operation 30 times, it is suspected that the abnormal noise is due to some other factors.)

4. After elimination of abnormal noise, repeat the operation shown at left five more times.

5. Run the engine at idle for 1 to 3 minutes to make sure that the abnormal noise has been eliminated.

If abnormal noise is not eliminated, clean the lash adjuster.
refer P115733.




I found this very helpful. As a result I rechecked the engines oil level on a level surface and found I had overfilled.

I drained the oil out and refilled so it was below max (level surface) and then repeated the above pattern about 7 times at which point the audible clicking stopped and then, as advised, repeated the pattern another 5 times.

I noted the oil was pretty dirty and a bits of light foam floating on top. I note the caution above: "If oil is deteriorated, air is not easily separated from the oil, increasing the amount of air contained in the oil.". So as I see how the clicking goes I'll keep that in mind and contemplate an oil change.

Following that, if the problem persists, I'll clean* the lash adjuster.

(*Yet to determine how.)

I guess I can say from experience now that for my car a tick can signify too much oil in the sump. Since adjusting the volume the ticking has largely gone. I've had to a couple of times to redo the procedure but nothing like before. If I'd known of this I'd have saved a lot of worry and some bucks on lifter cleaner bottles over the years.

I've yet to change the oil so I can't say whether the occasional tick is due to the old oil which still has air suspended in it. I'll make a note after I do.

I wonder if that is due to the oil getting more aerated by the crankshaft dipping into the oil.
Followed by some micro bubbles of air ending up in the lash adjusters.