Noisy valves after rebuild of TB42S

Hi folks , after weeks of 'terror' hanging my old bones over the big engine ... waiting for parts ... figuring out 'how do I do this and not that' ... the big engine is running again.
Proudly I can say 'at first go !'.

The first start after the head and more jobs was preluded with a few minutes of gently letting the oil find its way in the engine again. Deliberately run the engine with Diesel spec. oil to clean any left over water/ oil goo.
(Soon I will write a quick note how crazy I cleaned the enige after the disaster) .
Then the big moment was there : 'wil it run' ?
After all my mechanical engineering training is some 50++ years old and I became a full time photographer sometime in 1977 :D and never did a big mechanical repair job like this before..... (Besides working at a ship yard early 1970's and building my own Dune Buggy in 1981 :-) )
Turned on the petrol pump (electric): .... nope ! Switched to LPgas : Yesss !!! Let it run 30 seconds as I had not put in the coolant yet. Then turned off , let it sit for a few minutes - over to petrol : 'as if I turned on a light bulb' running too high revs. Turned off after some 15 seconds and filled with coolant. Then did a few idle runs on both LPgas and Petrol, adjusted the carby down to 650 RPM , adjusted the timing from 12 to 8 degrees (all on petrol now) and gently let the engine get warmer. I have a electric water pump and fan by Craig Davies and that kept the top radiator temp at 85 degrees. Eventually let the engine idle for 30 minutes, oil pressure was as ever , revving up the oil pressure increased normal.
So far so good - quite happy even though I fully realise it is a 400K engine with only a part rebuild.

Just one question:
The valves are quite noisy now - I set the factory valve spec setting of 0.38 mm as accurate as possible , it appears (with stethoscope) that the number 5 and 6 cyl are noisier as the others. But hard to be sure. The valves are definitely noisier as before rebuild , but the engine runs more ... how do I say that ... equal over all cyl. Nice like: tak tak tak tak tak tak tak , not like tekke tik takkkee tak tik tok :D :D . The engine even developed a magic cadence - kind of an incredibly slow sinewave sound.

I set the valves when the engine was cold - as it could not run yet. Should I do the settings again with a warm engine ?

thanks :
Jacob

Hi Jacob.
I just remembered of an 4 cylinder 22RE engine on a 4Runner that I once owned that required the valves to be adjusted hot. You had to idle it up to operating temp, open the valve cover, adjust two cylinders, close the cover, idle it to temp again, open again, adjust the two remaining...

That said, you got me curious if the TB was something like that and I found on the manual that the clearance you used cold is actually meant to be for hot scenario. In a cold scenario they should be a bit tighter. The manual doesn't mention that thing of doing two, heating again, doing some more two, etc, but it kinds of make sense to me. I am by no means an expert on the subject, so please, take your own conclusions. I just meant to add to the discussion.

Cheers!

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Thanks for this - the info I have sort of confused me as it stated the ame for hot and cold setting. Your info makes a lot more sense.
Will do that and see how it goes.
Unfortunately it looks like the whole rebuild was lost time - the first trials point to coolant loss again.
I was hoping to avoid a new head ....
At least got some training now :D
But who knows .... maybe maybe I am wrong and the engine behaves better with proper tappets settings.
thanks again - I will let you know:
J.

yep set them hot, not warm but proper burning your fingers hot

BillyJ Legend has got me thinking that Ambient Temperature/Hot Hauling Usage regional conditions might alter settings when needed versus old school set in concrete Nissan manual bible specifications Australia wide?
All I nuffy know is that whilst flogging our old TD42 towing up in our Northern Territory last year full tilt sun up to down it would clack away at idle each night whilst easing down for a snooze.
Back home in Victoria with less than 4hrs colder north to a border they’re back as tight as free needed I believe now?


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