how do i find TDC if i cant see timing marks?

[admiralslater]

Not on a diesel but yeaago with my father we stuck a screw driver in the plug hole and moved the flywheel back and forth and felt tdc. I know I know but it worked

[blueazimuth]

You can make valve adjustment as complicated or as simple as you want. All the above sound fine but why not keep it simple?

What could be simpler than what Lookinggoodrock suggests?
KISS ...

A diesel engine won't start by turning it over to adjust the valves but, by all means, take the key out and turn off the start battery switch.

[Barney21]

Originally Posted by Wotname

Not sure why you need to see the timing marks to adjust the valves. Rotate engine until both valves are fully closed and the existing valve clearance is at a maximum. Reset to desired value.

Having an engine with a decompression lever is helpful .

Curious - what engine are we discussing?

Just do this ,is very easy . No need for timing marks etc,no books!

[RaymondR]

Have not adjusted valves for a long time but used to do it with the engine running with go/no go feeler gauges on petrol engines.

[Cheechako]

Originally Posted by RaymondR

Have not adjusted valves for a long time but used to do it with the engine running with go/no go feeler gauges on petrol engines.

Me too on gas engines, but diesels throw oil about 2 feet with the cover off!