Merc 4.3 oil change

[Rob406]

Having trouble getting suction through my dipstick tube. I have two new hand pumps, one which threads on to the dipstick and one which came with a rubber tube the ID of the dipstick. Neither are successful in their own ways.

Is it an absolute necessity to heat the oil? Did not think I would have this much difficulty with ~100* oil. Will not be able to run the motor till tomorrow.


Thoughts?

 

[achris]

...Is it an absolute necessity to heat the oil? ...

Yes. For 2 reasons.

1. You should have the engine at operating temperature to change oil (that's 'mechanics 101'!) so it can carry all the impurities away when the oil is drained/sucked out.
2. The oil really is much thinner when hot.

You should never be changing oil cold (unless it's full of water and you don't want to emulsify it, but that's a whole other topic)....

Chris.....

 

[QBhoy]

Hi
all is forgiven if you are not totally up on all this...but AC Chris is spot on. You really need to get up to absolutely full operating conditions to even think about changing the oil.
You need it fully warmed to suspend all particles within the oil equally
and you need it warm as can be to be able to take the oil out in good time before it gets cold and viscous. Ideally you want to get the engine under load to do this properly or you might find it doesn’t heat up sufficiently to be able to do it properly...despite the temp gauge suggesting you’re there. Trust me, if you do this and get half way through the oil change and it all slows down...you’re past the point of no return and you don’t have enough oil to start it again. Do it properly or not at all really. Sorry to be harsh. As Chris says. It’s rule number one to get the oil totally at operating temp to suspend all particles equally within the oil. No use at all any other way.

 

[Rob406]

Trust me, if you do this and get half way through the oil change and it all slows down...you’re past the point of no return and you don’t have enough oil to start it

That was another one of my concerns. I think ill just fish a tube up through the drain plug and funnel the oil out throgh the sump. Pumps are getting tossed. Thanks for the responses guys.