Recently, one of my autogate arm seems to be screetching even after the gate has finished opening, so I wanted to get some WD40 to stop the whining..
But to open the plate secured onto the tiled floor by 4 hex socket srews. I bought some hex keys (long type) but cannot get it opened because lack of leverage.
Is there a way to open these hex sockets, I am sure I can stop the screetching if I can open the plate and spray some WD40 into it?

If you are using those el-cheapo rm2 type...forget about the extra leverage as your hex key would easily give way.
Get an Umbraco...sounds something like that... brand and you can use an adjustable wrench to add torque....till the hex bolt give way...

Note that wd40 may just wash away the bearing grease and add more to the problem later on.

not rm2 but rm15, I will ask the hardware shop tomorrow. You are right, I need to open and see whether it is grease or WD40 needed.
It is hard without the right tools.

Autogate arms are not necessarily simple motors made just to swing the arms. My unit has a clutch mechanism. Do you think you know how to adjust or service the clutch? It need not be just lack of oil.

Perhaps you may be thinking water got in to the base unit? That's even worse - then it would be a bigger job of cleaning out the mechanisms.

The rubber seal may be destroyed when you open the base plate - do you think you can replace the rubber seal?

Think of all the consequences - I would just call a gate-man and leave it to the experienced people.

OK, some success, managed to turn the hex bolts after the HW shop guy sold me a metal pipe (rm2) to extend the leverage, it works, I got more leverage. Guess what, I broke the hex socket head so I have stopped trying to open the rest..

do you have anyone to recommend?

oh! surprise! I got the problem solved by loosening the connection between the gate and the turning arm! ok this autogate will prob see its 10th year.the screetching sound is gone. Wow, wonder what the technician .will have charge and what reason...

Not sure if your mechanism is screeching or its the external arm linkage to the gate which usually have a ball bearing there. That BB can be jammed after some years, although WD40 is only a temp fix but changing that little ball bearing will usually solve the problem on the outside. Any noise from the motor mechanism will need a total overhaul in that department. I've done mine many times as rain water gets in not only from the cover seal but the shaft seal. Somehow, these local stuff are not made to last for even a decade. They go kaput so easily. Terrible Made in Malaysia stuff actually. 5 years optimum performance is all I give, after that, anything may happen.

Use STAINLESS STEEL BOLTS for your automatic door mechanism...NOTHING else. Coat them with a little LM grease before fastening them and will ease removal next time.

Here's a tip:
I get ALL my "specific" machinery BOLTS and NUTS from this place.
They almost have every imaginable bolts and nuts for construction and machinery or any other precision use, small to large, steel, stainless steel types..and you can buy any quantity 1 piece or 1,000 pcs, no limit. I found they have exact stainless steel equavalents types when I refurbished my Linn Sondek turntable. Best to bring along sample for match.

Yew Siong Industrial Supplies Sdn Bhd
24 Jalan PJS 11/24 Bandar Sunway
Subang Jaya, Selangor 46150
Malaysia

Disclaimer: NO affliation with them nor do I get kickback from any personal recommendation.

__________________
Good judgment comes from experience. Experience comes from bad judgment.

Thank you all the same.

OT. Nice TT!