ONE LIFE LIVE IT. D90

Active Member
Hi fellas

Planning on doing a coolant flush on my 300tdi tomorrow. Firstly because it looks like it hasnt been done for a long while, and secondly due to poor heat out of the heater.

Tried to do some research, but still unsure hense the thread.

Inside the header tank, it is lined with rusty water residue. Despite having no cooling issues at all, do you think its worth using a flushing agent of some sort? Or dish washer chemicals? The reason i question it is - i dont want to expose a leak, from a perfectly working cooling system. Other than a possibly blocked heater matrix (luke warm heat from heater).

Ive read that the latest OAT anti freeze isnt really suitable. So would this one be up to the job in a 95 300tdi?
http://www.ebay.co.uk/itm/331037355289

Lastly, is there anything i need to be carefull of. Ive read that anti freeZe is bad for animals, but its going to be near impossible to contain it all. And what is it like on paint work?

Many thanks in advance.
 
Yep thats the one good old blue glycol works just fine.
Wont hurt paint, but worth rinsing the area clean afterwards.
Dont leave any open containers about as animals will drink it as its sweet tasting and screws the liver up.
Glycol coolant is meant to be changed every 2 years to keep the corrosion inhibitors up to strength, oats on the other hand can go 4 years
 
Cheers lynall. I'll get that stuff then i think.

I want to give the cooling system a really good flush out with the hose pipe. Especially the matrix. How am i supposed to do this if its risky to animal with getting coolant on the floor?
 
Catch what you can and rinse spillage away with hose pipe
Has the 300 got the drain point in the block on the left side near the front approx between cylinder 1 and 2?
 
Catch what you can and rinse spillage away with hose pipe
Has the 300 got the drain point in the block on the left side near the front approx between cylinder 1 and 2?


Yes, but it still sprays everywhere unless you have a big tray.
 
Remove the drain bolt slowly until you have a nice steady stream bit like a beer induced slash!
 
Hahaha cheers guys. Did the coolant flush today. It was well due.
A query though... I Removed the thermostat, and it had 75 stamped on it. Which i beleive is a cooler stat. Why though?

Also, after the coolant flush, including flushing out the heater matrix thoroughly. The heater is no warmer. Its still the same luke warm air. Why?
 
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I'd go buy a new heater matrix mate, they are only about £30 and can make a big difference. It's not a bad job to do either, there are plenty of instructions on the internet if you need help.
 
Absolutely certain that the thermostat should be rated at 88 degrees C - I've recently changed mine and it made the world of difference and to be honest this was a cheap one off the internet.
 
Made a big difference to the heater in my series 2 tdi now runs pretty much 88 all the time, same as my 90.
Neither heater is brilliant but defo better than lukewarm
 
I replaced my matrix last year due to a leak,also removed the heater blower and opened it up was full of crap and all the foam seals had perished so made some new seals and adjusted the linkages that control the flap,wot a difference it gets quite warm now:)
 
One other thing to consider is that whilst the heater box is off the car you can make it gas tight. Get some aluminium foil air conditioning pipe tape and use this inside and out on every joint in the heater box (between the hot area and the cold bypass as well as between the inside and outside) plus replace the foam on the flap and between the matrix and box then give the flap hinge a lube. Then make sure the seal between the heater box and bulkhead is intact. Lastly make sure that the cables are properly adjusted. If you do all that it will start to pump out heat but it takes maybe 5-7 miles to heat up fully. I've got mine up to that point and next job is to affix insulating foam to the outside of the heater box.
 
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