difficulty priming 4.3 oil pump after oil + filter service

[Griff43V8]

anyone else found that 4.3 pump wont prime after oil and filter change - only c 18k miles from new and excellent pressure and suitable oil

Specialist had to pack pump to prime - c.7k miles back (still excellent pressure), but scares me leaving with new specialist / attempting to do at home

[GreenV8S]

That can happen if you leave it draining too long. I use an electric pump to ciculate oil round the whole system after refilling, which removes that possibility, but that shouldn't normally be necessary - if it doesn't reprime within a few seconds on first startup, pack the pump with vasseline and try again.

[Belle427]

I think its been mentioned before but some choose to drain and refill the sump first and then replace the filter priming it as much as possible.
What difference it makes i dont know, as said usually problems occur when its been left too long.

[Sagi Badger]

Yep long long time ago with my SD1 (sold to fund moving into the first house) I had the non priming experience. Scary stuff. Tub of Vaseline and some cursing that this was necessary...

[Griff43V8]

Thats what he did, seems crazy that that should be necessary and having witnessed it fist hand, I am scared stiff of entrusting an unknown mechanic in not running engine ten secs to see if it will self prime to save extra work....

If doing it at home, whats best way of tackling it - havent looked to see how u would pack the pump if necessary

As an interim compromise (because car has been standing over 10 yrs) if I leave filter in place and just change the oil to drive it to dealer to have filter changed will that definitely keep it primed?

[Adrian@]

Being a 4.3 there is a small chance that it has an 'tadpole' adjustable pressure relief valve, which adds complexity to a simple job. A@

Edited by Adrian@ on Friday 29th March 10:13

[Belle427]

Not sure if the 4.3 is the same but you can buy a priming tool for a drill that drops down the distributor hole and engages with the oil pump drive.
Obviously distributor needs to be removed to do it so marking its location first is advised.
Ive seen some people having problems with that too though.
Ive also read that some choose to prime and change the oil filter, run the engine and then drop the oil in the sump.

[Griff43V8]

.....every engine has its design flaws - how can cos produce millions of engines without evolving such flaws out...
Now I am scared to do it myself and scared to let a garage do it