Coolant change for 90 V8

The hand book talks about draining the block from the bungs on either side of the motor when changing the coolant, is this necessary ? Cheers

Not really.

i did this recently after i had a burst pipe and had to run a full laning weekend topping up with fresh water all the time.

as such i wanted to drain as much water out as possible to replace with 50:50 antifreeze.

i pulled the bottom rad hose and a lot of water came out. i undid the block plugs (first time ive done them) and around the same amount came out again.

as such, i would recommend the only way for a full drain is to drop the block jackets aswell.

remember you may also need to drain your heater circuit to get the last of it out.

Yes is surprising how much the block holds, but just for antifreeze replacement all that I do although it takes a lot longer is drain the rad, refill, run the engine for 5mins and drain, refill again etc etc to ensure that the whole system is just plain water.
I don't think I can even get to my plugs without laying underneath they are even difficult to see from under the bonnet, infact I don't think I've never seen them on this motor .

Taking off bottom hose to drain and then back flushing should do. Agree with Discool, getting at the block drains is a pain.

classic kev said:

Taking off bottom hose to drain and then back flushing should do. Agree with Discool, getting at the block drains is a pain.

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Hey thanks for your replays, Here is what I did. I pulled off bottom hose from radiator drained and then pulled off heater hose, stuck garden hose into heater hose and flushed for about 5min. Then I stuck the garden hose into the top of the radiator and with my hand over the bottom out let flushed back through the other way, all with the heater control on Hot. Then refilled with new antifreeze, its turned out ok but a bleeder would have made for a quicker job of it.

That's the way "a full flush" the end result is the same with clean water through out the cooling system.

I can't use a hose pipe they are banned in my part of the world, we have a shortage of water.. so they say.

discool said:

That's the way "a full flush" the end result is the same with clean water through out the cooling system.

I can't use a hose pipe they are banned in my part of the world, we have a shortage of water.. so they say.

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Thanks, yeah I feel like its had a good flush, but like I said, a bleeder to burp the air out would be a big help. Maybe next I will leave the heater hose off until I can see the new coolant come through.

Never have a problem with my 3.9 disco as it self vents via the expansion bottle cap so I just refill slowly, but in my old 3.5RR days with the expansion bottle with the half twist metal cap -a different system- I always had a problem untill a LR tech told me to raise the front of the RR so the top of the rad was the highest point and then slowly refill, but if air does get in and it always did in my heater matrix the only thing to do was drain and start again.

Fortunately my driveway is on a slight slope so I refilled with the vehicle facing upways and it always worked after that, so a 'top tip' from Land Rover in the days before Forums.

i dont wish to dig my heels in unneccesarily but i thought the block drains were a easy enough, and i have tubulars fitted.

both are easier accessed from underneath.

anyway just for reference if anyone in future reads this thread...

Mr Noisy said:

i dont wish to dig my heels in unneccesarily but i thought the block drains were a easy enough, and i have tubulars fitted.

both are easier accessed from underneath.

anyway just for reference if anyone in future reads this thread...

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Any chance of a pic of ya tubes ?