Do you know how I open up the oil pump? There's two hex screws which I've removed but then it isn't obvious what the next step is. It looks like there's a bit of a lip which looks like needs to be also prized open but then there's no slot as such. Bit puzzled as to what I need to do to open it up?! I've been told I should check it out to see the condition.
having just installed the GDU again today....yes it makes absolutely no sense to remove it from underneath. I installed it back in today with relative ease going in from the top with all the tail section removed, and As you point out...not having to remove the pump or anything. Lessons learnt!
another update to this thread, and may it help a fellow newbie in the future! I successfully and very easily primed by GDU pump after a refill.
- unplug the hose line from pump to radiator.
- use a small syringe, squirt new oil into the pump and down the hose until both start seeping out. Clean and reconnect.
- turn the wheels by hand backwards. This sucks the oil in and fills the pump.
- Disconnect the top hose line that connects to the top bung. Again turn the wheels by hand forwards, and after maybe 20 seconds/15 or so spins, it started to seep oil out. Job done.
@rojid ... and a note regarding the priming of the pump. I have found that on at least one of my GDU's that the pumps prime is lost after the car is left sitting for a few months...
I think this happens when the oil slowly (very slowly as it takes longer than a month) seeps back through the pump under the force of gravity... leaving the pump at least partly empty... not enough to self prime. This only happens on my older GDU which has some wear marks inside the pump's anodised aluminium housing.. I suspect that enough clearance to let the oil slowly leak back...?
So my process is to check the pumps prime immediately prior to a race meeting... using the same last step as Rojid lists above/... remove the return hose from the oil cooler that mounts onto the top of the GDU and turn the rear wheels by hand (normally takes about 15-30 seconds)... when oil arrives... you know you have prime. If not... you will need to re-prime it.
