2.0 l petrol coolant change/top up/bleeding etc

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smith335
Junior Bongonaut
Posts: 15
Joined: Tue Aug 07, 2018 10:32 pm

2.0 l petrol coolant change/top up/bleeding etc

Post by smith335 » Tue Oct 23, 2018 10:03 pm

Hi to all

need some help/advise please

I have looked at many posts about bleeding the coolant system for bongos, but most of them refer to the v6 petrol or the 2.5 derv.
on one post i read that the 2.0l petrol does not need to be bled in the same way as the other two types of engine.
and there for can been drained/filled in the same way as a normal car.

is this true....??


my bongo is a fresh import and the coolant looks green, and has not been changed since landing in the uk.
would this be old school green anti freeze or the jap/mazda oat stuff?? sorry dont know the correct names/terms.

i am very sorry if this has been done many times before but i just need a little help please..

thanks in advance


Aaron
2004, 2.0L Aero City Runner
Bob
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Location: North Somerset

Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by Bob » Tue Oct 23, 2018 10:20 pm

You are correct.

The 2 ltr petrol is like any other car, as for the existing coolant - no idea, but since it's a simple job to flush and change it, plus winter coming, I'd replace it.

Just make sure to flush out all the old stuff. :wink:
smith335
Junior Bongonaut
Posts: 15
Joined: Tue Aug 07, 2018 10:32 pm

Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by smith335 » Wed Oct 24, 2018 8:03 am

Thank you for your reply and info.

yes winter is coming and i would like to change the coolant, tested it and its only showing protection down to -7 , so not good enough.
my first thought was to drain only a litre of coolant out and add some fresh neat coolant just to bring it up to a better level of protection. i am very short on time. so this way would be good...
but then i am not 100% what the coolant is that is in there.

any advise/ tips how to drain the coolant and refill on the 2.0l petrol
is it just a case of draining the coolant via drain plug on the rad or dropping a hose off.
still getting used to the engine set up.

kind regards
smith335
2004, 2.0L Aero City Runner
TheLongRoad
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Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by TheLongRoad » Wed Oct 24, 2018 9:36 am

I have a 2.0ltr petrol and have recently done a lot of work on the coolant system, bypassing the rear heater etc that you have no doubt read about in other posts. I decided to change to the long life anti freze so did a system flush to remove as much of the old stuff as I could.

To drain the system, remove the under body panels as it just makes life easier getting at the hoses. There is a drain at the bottom right of the radiator, then another small drain plug on the large top steel upper hose. It seemed odd having it up there as it's not at the bottom of the system. However removing that gets more coolant out. Next I un-clipped the bottom hose under the engine and the hose to the rear heater. Sounds a lot of faffing but it's straight forward and is the only way to get most of the coolant out.

I flushed mine four times - eventually clean water came out so I was happy I'd got all the old coolant out. Each time I measured how much I'd drained and never got the full 13 litres out - max I got was just under 11 litres. I guess there are so many twists and turns in the system and inside engine which account for that.

Topped up with the new coolant mix to the prescribed concentration. The system self bleeds. Just leaving the engine ticking over doesn't do the trick, you need to rev to 2000 rpm for the pump to get a good flow going. At this point you'll here a lot of gurgling behind the glovebox or see bubbles in the header tank. Top up as required. I only had to add 1/4 litre once it had finished gurgling and it's been at a constant level since.

If you have the excellent Haydin Coolant Alarm fitted it might give a false alarm with the new coolant. Mine did but stopped soon after the work had been done. Just a final check of your hoses for leaks and you're done. I used the HCL Worm Drive constant tension clips as a replacement to the old Mazda spring clips.

Hope this helps.

Send a PM if you need to ask more questions - happy to help if I can.
2002 Friendee 2.0 ltr Petrol.
Bonneville
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Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by Bonneville » Wed Oct 24, 2018 12:01 pm

I drop mine at the bottom hose. Initial fill through the drivers side hose that comes off the inlet manifold and goes to the rear heater. That way you fill from the bottom up. Final fill is through the expansion tank as usual.
I differ in that I bleed it as per all other cars; squeeze those hoses and wait. Top up and listen for the gurgling when you squeeze. Wait some more. Repeat until it's filled. Pop the little hose off the front of the thermostat housing (expansion tank return) and let the air burp out. Put hose back on. With cap off, run engine (no need to rev high, just blip it to clear the cavitation in the water pump).
Don't let any engine run for more than a minute or so with the cap off. Boiling point of water rises 2-3 degrees per 1 psi of pressure so get the cap back on and run it to temp. Check warm air comes out of heaters and check bottom and top hoses periodically. Top hose should get warm after a few minutes as stat opens.
Check level the following morning and again every now and then for a week or so as it will settle over time. I bleed everything this way including some notorious horrors like 6-cylinder BMW's that lock air at the back of the head. Just needs patience and a good feel for the hose squeeze.
smith335
Junior Bongonaut
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Joined: Tue Aug 07, 2018 10:32 pm

Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by smith335 » Wed Oct 24, 2018 9:07 pm

Excellent info guys , thank you

any tips on flushing the system.

regards
2004, 2.0L Aero City Runner
TheLongRoad
Bongolier
Posts: 480
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Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by TheLongRoad » Thu Oct 25, 2018 6:45 am

Buy a bottle of rad flush. Drain system, fill with water and add rad flush. Take Bongo for a short drive and leave overnight. This gives time for the chemicals in the rad flush to do their job. Next day drain and fill with water. Warm engine again and drain again. Repeat as required until you are draining clear clean water out of the system. Then do your final fill with the new coolant antifreeze mix. Might be a little OTT but my Bongo is a hobby and I enjoy working on it. Plenty of videos on YouTube- there is one called super flush and the link was posted by someone on this forum. Have fun.
2002 Friendee 2.0 ltr Petrol.
smith335
Junior Bongonaut
Posts: 15
Joined: Tue Aug 07, 2018 10:32 pm

Re: 2.0 l petrol coolant change/top up/bleeding etc

Post by smith335 » Thu Oct 25, 2018 11:10 am

Thanks for the help...


will get it all done asap.

many thanks
2004, 2.0L Aero City Runner
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