M274A5 MULE 2 CYL. TICK ON STARTUP QUESTION

[RAS1]

Hi!
I need suggestions. I have a 2 cyl. mule that ticks and misses on passenger side (right hand) cyl. when cold.

I have changed the head to a genset head, no spacer.
I have installed new lifters.
I have changed the oil and filter multiple times.
I have added marvel mystery oil to the engine and gas tank.
I have only driven it 5 miles or so since working on the engine.

What would cause this? plugged oil passage? junk engine? should I pull the rubber valve stem gaskets out?

Here is a link to the youtube video of it running cold. Note, it is a very short 8 sec. video. Listen carefully, you will here it tick for the first 3 seconds and quiet down on its own.

https://youtu.be/XCbJpgLxVOk

Let me know your thoughts.
dave

[HoustonMule]

If I let my mules sit for weeks without running them one will have a lifter tick for a minute or two and the other may tick for 10 minutes. The ticking will eventually go away. If I run them every week typically no ticking. What oil are you running??? Yes the Marvel Mystery added to oil will help the lifters.

[RAS1]

Update on the ticking, fixed.

I changed lifters, changed oil and filter 3 times, did not solve the cold start tick.

Changed oil using risilone (about 1/2 quart) remainder using purple power 10w30. Started up no ticking, has been about 2 weeks, every subsequent start has been perfect.

Thanks
Dave