Orange staining in the expansion tank
Discussion
Hi Guys,
Just about to buy an R-Reg (98/99) Mark 2 Japanese MX5. Really looking forward to joining the ranks of owners
One question though. Dark Orange/brown staining in the expansion tank, patchy though.
It looks like rust, smells like rust, probably is rust. Is it possible (serious question) that it could simply be rust and nothing more sinister?
Some notes on the car..
The coolant is very low (engine serviced 6,000 miles ago and not touched since). What little coolant in there looks clear (although I can't be sure......the owner is topping it up today and telling me what happens).
Specifically I need to find out from them if it overflows (I believe that would be a head gasket problem) or dissappears (who knows what that is?!).
Opening up the radiator cap shows noticeable rusty bits inside the collar - leading me to believe the orange colour in the exp tank is indeed rust.
There's no gunk under the oil cap or on the dipstick, or in the rad or expansion tank.
The car has not overheated in the three years they had it, so that's reassuring - although the exp tank is covered with orange/brown inside top to bottom (possible just due to water sloshing around).
I would be very grateful if you'd tell me if I am on the right lines, or is there anything else I should be looking for?
PS the car has done 155,000 kilometers, 1.8, waterpump replaced at 115,000kms, coolant replaced once in three years (other than perhaps when the wpump was changed).
PPS The oil smells fine, in fact for an car done 155k it smell like new! And the expansion tank doesn't smell funny either.
Thank you
Just about to buy an R-Reg (98/99) Mark 2 Japanese MX5. Really looking forward to joining the ranks of owners
One question though. Dark Orange/brown staining in the expansion tank, patchy though.
It looks like rust, smells like rust, probably is rust. Is it possible (serious question) that it could simply be rust and nothing more sinister?
Some notes on the car..
The coolant is very low (engine serviced 6,000 miles ago and not touched since). What little coolant in there looks clear (although I can't be sure......the owner is topping it up today and telling me what happens).
Specifically I need to find out from them if it overflows (I believe that would be a head gasket problem) or dissappears (who knows what that is?!).
Opening up the radiator cap shows noticeable rusty bits inside the collar - leading me to believe the orange colour in the exp tank is indeed rust.
There's no gunk under the oil cap or on the dipstick, or in the rad or expansion tank.
The car has not overheated in the three years they had it, so that's reassuring - although the exp tank is covered with orange/brown inside top to bottom (possible just due to water sloshing around).
I would be very grateful if you'd tell me if I am on the right lines, or is there anything else I should be looking for?
PS the car has done 155,000 kilometers, 1.8, waterpump replaced at 115,000kms, coolant replaced once in three years (other than perhaps when the wpump was changed).
PPS The oil smells fine, in fact for an car done 155k it smell like new! And the expansion tank doesn't smell funny either.
Thank you
Edited by Andy Maxwell on Friday 5th June 08:50
Edited by Andy Maxwell on Friday 5th June 08:51
Antifreeze contains corrosion inhibitors. If it has been diluted with water or is just old coolant, it may well be corrosion from some part of the cooling system.
Check the rad for leaks. My 98 mk1 had a small leak when I bought it in 2013. I only noticed it when snooping around, as the leak was so small, what little was leaking out was puddling up on the under tray and being dispersed when going for a drive.
Check the rad for leaks. My 98 mk1 had a small leak when I bought it in 2013. I only noticed it when snooping around, as the leak was so small, what little was leaking out was puddling up on the under tray and being dispersed when going for a drive.
Thanks thecremegg. Glad we share the same opinion, really reassuring.
I purchased the car on Saturday (see 'Show us your MX5' post on 8/6/15) and have given it a few runs - the coolant is still clear. So yes, looks like proper coolant hasn't been used and the staining is rust. The owner told me that "it has always been like that", they had it for 3 years so I figure if the head gasket was going to go it would've gone already
I purchased the car on Saturday (see 'Show us your MX5' post on 8/6/15) and have given it a few runs - the coolant is still clear. So yes, looks like proper coolant hasn't been used and the staining is rust. The owner told me that "it has always been like that", they had it for 3 years so I figure if the head gasket was going to go it would've gone already
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