Coast px1 flickering after cleanup

I got a coast flashlight from my brother in law not long ago and it is just right for using at close range out to midrange and it even has a slightly warm tint to it.
My only problem is in the threads of the twist head -it had grit in it, so I put some rem-oil on it and cleaned it up and got it smooth.
Now it flickers every now and then, but I can twist the head and it seems to clear up for a while. I really need to get that twist head off of it to clean it better and get the rem-oil off of the inner contacts--which I suppose is causing the flickering.
I can't find anything on the internet that will show me how to get it apart. Everything else seems alright. Can anyone help me please? Thanks in advance.

I have owned a few coast lights. they have all been glued together. if you send coast the light they will replace it for free.

Ok, thank you. The newer ones put out more, but they drain the batteries quicker. This one is probably 2 years old. It is just right for holding in my mouth when working on a vehicle.
I prefer the maglite solitaire LED, but I don't like that full regulation on it. When working on a vehicle all night it is frustrating for the flashlight to go out without warning and the have to keep replacing batteries every couple of hours.

I forgot to mention that I also like the warm color temp the led has on it.
That is why I traded my brother in law for it in the first place and if I got
another it probably wouldn't have that. Their "pure white" beam isn't warm enough
to sell me. Maybe I'm just old school, but extreme whiteness in a flashlight is just
sooo unflashlight like.

Edit: I do like whiter incan bulbs because I know it is higher in CRI. Also I think I have the ol coast fixed. I used some silicone grease on the twist head threads and it quit flickering (so far).