Urgent help needed with rad removal!!
Discussion
Hi folks,
Decided to pull the radiator this evening to see if a reverse flush would sort it.
Following the Rod Grainger manual, top/bottom/reservoir hoses removed, fans disconnected, 2x 12mm bolts removed (decided to leave fans on and remove them when out of car.
However, when lifting out it appears that the a/c pipes are somehow attached to the bottom of the rad
Doesn't mention this in the manual and it does deal with a/c cars as it mentions that the a/c fan will need disconnecting too.
It's not the auto trans. pipework either as mine is a manual.
Can anybody advise as I'd like to get it flushed tonight before the light goes!!
Decided to pull the radiator this evening to see if a reverse flush would sort it.
Following the Rod Grainger manual, top/bottom/reservoir hoses removed, fans disconnected, 2x 12mm bolts removed (decided to leave fans on and remove them when out of car.
However, when lifting out it appears that the a/c pipes are somehow attached to the bottom of the rad
Doesn't mention this in the manual and it does deal with a/c cars as it mentions that the a/c fan will need disconnecting too.It's not the auto trans. pipework either as mine is a manual.
Can anybody advise as I'd like to get it flushed tonight before the light goes!!
am prob a bit late now but as i remember when mine had air con before i ripped it all out, you need (well, it's easier) to take the undertray off. with the front of the car jacked up if you stick your head in from the front you can see where the ac pipes run from under the rad across the top of the front cross member. i can't remember them being attached to the rad, but then i ripped all the ac out, then replaced the rad so can't remember if the two were attached. i seem to remember the pipes being secured with some small clips with 8 or 10mm bolts on though
Thanks for that Dylan.
It was up on ramps in the garage so I'd already whipped off the undertray.
It seems the book is a bit misleading - the bottom two fan bolts on the LHS fan (if you're in the driver's seat) also secure the a/c pipes, so you have to take these out - then you can lift out the rad without drama!
So on the bright side it's all out - however, doesn't look to be much wrong with it. No obvious fin damage or splits in the plastic tanks, and although there was a fair bit of silt when I took off the bottom pipe, I reverse flushed it and the water ran clear within a couple of seconds, so I don't think it was blocked or really silted up.
So, not sure what to do now. Is it worth getting it pressure tested, or just buying a new rad at 80 quid? Will buy another new rad cap if MX5parts ever get them back in, and might as well replace the top & bottom hoses and the thermostat while I'm at it. Will flush the whole system when I do it.
Thoughts?
(For anybody who missed the original thread, car always smells of coolant although no obvious loss. In very hot weather smell is stronger, coolant in reservoir boils and level rises but temp stays in the middle. Guage started to rise a couple of weeks ago when very hot weather combined with traffic jam. Both fans work and cooling fan kicks in at about 100 degrees C. Initial thoughts were rad cap (but new genuine Mazda one a couple of years ago), or blocked/leaking rad causing coolant to boil and cap to release it into reservoir.)
It was up on ramps in the garage so I'd already whipped off the undertray.
It seems the book is a bit misleading - the bottom two fan bolts on the LHS fan (if you're in the driver's seat) also secure the a/c pipes, so you have to take these out - then you can lift out the rad without drama!
So on the bright side it's all out - however, doesn't look to be much wrong with it. No obvious fin damage or splits in the plastic tanks, and although there was a fair bit of silt when I took off the bottom pipe, I reverse flushed it and the water ran clear within a couple of seconds, so I don't think it was blocked or really silted up.
So, not sure what to do now. Is it worth getting it pressure tested, or just buying a new rad at 80 quid? Will buy another new rad cap if MX5parts ever get them back in, and might as well replace the top & bottom hoses and the thermostat while I'm at it. Will flush the whole system when I do it.
Thoughts?
(For anybody who missed the original thread, car always smells of coolant although no obvious loss. In very hot weather smell is stronger, coolant in reservoir boils and level rises but temp stays in the middle. Guage started to rise a couple of weeks ago when very hot weather combined with traffic jam. Both fans work and cooling fan kicks in at about 100 degrees C. Initial thoughts were rad cap (but new genuine Mazda one a couple of years ago), or blocked/leaking rad causing coolant to boil and cap to release it into reservoir.)
I Am Milk said:
To check your Rad properly, put the hose in the filler neck (where the rad cap goes) whilst the rad is vertical. Nothing should come out of the top hose hole. If it does your rad is blocked, and not working to it's full capabilities.
Really? OK, will check that.On reflection, I will change top & bottom hose, stat, radiator cap, and run it with water & rad flush in for a bit before filling with coolant and see if that is any better.
NiceCupOfTea said:
I Am Milk said:
To check your Rad properly, put the hose in the filler neck (where the rad cap goes) whilst the rad is vertical. Nothing should come out of the top hose hole. If it does your rad is blocked, and not working to it's full capabilities.
Really? OK, will check that.On reflection, I will change top & bottom hose, stat, radiator cap, and run it with water & rad flush in for a bit before filling with coolant and see if that is any better.
NiceCupOfTea said:
Lazza - tips on flushing the rest of the system?
Surely more complex than sticking a hosepipe in the top hose and a bucket under the bottom hose!? Stat needs to come out and heater set to hot, anything else?
I've never done it myself but that sounds reasonable to me. You can probably do the heater matrix separately using the pipe from the thermostat housing (if I remember the layout correctly - it's very possible I have that wrong though).Surely more complex than sticking a hosepipe in the top hose and a bucket under the bottom hose!? Stat needs to come out and heater set to hot, anything else?
Edited by MX-5 Lazza on Wednesday 21st July 08:49
have you done the waterpump/any evidence it has been done recently? mine was running spot on when i bought it but i changed the rad/stat/cap/water pump when i did a cambelt change just so i knew i wouldn't (hopefully) have any issues in the future.
if the coolant boils in the expansion tank, it's obviously circulating though. hmm. i'd change the stat first, seeing as it's cheap - i think mazda respecified the opening temps of them, as the later design i got to replace my, i assume, original was slightly different
if the coolant boils in the expansion tank, it's obviously circulating though. hmm. i'd change the stat first, seeing as it's cheap - i think mazda respecified the opening temps of them, as the later design i got to replace my, i assume, original was slightly different
OK,
Or should I just buy a new rad?
Here's the old one:
And before I washed it through - you can see a dark patch at the bottom, not sure why, it's been in the garage for 10 days so shouldn't be wet. Possible there is a tiny leak there?
- thermostat replaced (old one looked OK but you never know)
- top/bottom hoses replaced with pretty blue ones (may regret that one as the bottom hose was shorter then the old one so I hope it reaches to the rad!)
- radiator thoroughly flushed forwards and backwards. Not much sludge in it. When directing the hose through the cap hole, there was some water coming through the top hose hole - does this mean there is a blockage?
Or should I just buy a new rad?
Here's the old one:
And before I washed it through - you can see a dark patch at the bottom, not sure why, it's been in the garage for 10 days so shouldn't be wet. Possible there is a tiny leak there?
Edited by NiceCupOfTea on Wednesday 21st July 16:51
you're not loosing any coolant though are you? at all? front main seal look ok?
my rad looked in better nick than that to be honest, but seeing as you can never see inside it, i knew it'd always be in the back of my mind and piss me off, no matter what you flush through it, how much pressure etc.
by all means give it a flush through and see if it makes any difference though, it's free afterall. i do repair rather than replace things every so often
as an ex k series owner though, i treat the whole cooling system as a consumable, probably overkill but it keeps me out of trouble
my rad looked in better nick than that to be honest, but seeing as you can never see inside it, i knew it'd always be in the back of my mind and piss me off, no matter what you flush through it, how much pressure etc.
by all means give it a flush through and see if it makes any difference though, it's free afterall. i do repair rather than replace things every so often
as an ex k series owner though, i treat the whole cooling system as a consumable, probably overkill but it keeps me out of troubleI had a problem with my cooling system recently, I'm fairly certain mine was to do with a bodge job clogging the thermostat housing T piece when it was fixed. As i'm OTT, I changed everything to do with the cooling system, and it's better now.
On another note, have you checked your Fan is coming on at the correct temperature? It could be the temp sensor at the back of the engine isn't working as you might think. Can be checked by sticking a thermometer in the radiator while the engine is running and checking it(they) come on at 97 (I think). Obviously the water will boil earlier with the system under no pressure but you can check the temp sensor is working.
On another note, have you checked your Fan is coming on at the correct temperature? It could be the temp sensor at the back of the engine isn't working as you might think. Can be checked by sticking a thermometer in the radiator while the engine is running and checking it(they) come on at 97 (I think). Obviously the water will boil earlier with the system under no pressure but you can check the temp sensor is working.
Not noticed any leaks. Not losing any coolant I can see.
Tested the fan the other day, it does work but it kicks in around 105 degrees. Is that too high?
Just put the car back together, filled with water and ran up to temp. Thermostat seems to work OK but couldn't check for leaks because I had a small geyser coming out of the rad cap
Water/coolant all over the garage floor Started boiling at 100 so killed the engine so unable to test fan, but as I say it worked before...
Tomorrow I will drain now it's on the flat, fill with flush, run, drain, fill with water, run, drain, and finally fill with coolant mix.
Shouldn't be any new leaks, new hoses pushed well on and have those sprung hose clips rather than jubilee clips.
Tested the fan the other day, it does work but it kicks in around 105 degrees. Is that too high?
Just put the car back together, filled with water and ran up to temp. Thermostat seems to work OK but couldn't check for leaks because I had a small geyser coming out of the rad cap
Water/coolant all over the garage floor Started boiling at 100 so killed the engine so unable to test fan, but as I say it worked before...Tomorrow I will drain now it's on the flat, fill with flush, run, drain, fill with water, run, drain, and finally fill with coolant mix.
Shouldn't be any new leaks, new hoses pushed well on and have those sprung hose clips rather than jubilee clips.
my rad looked better than that when i changed it for another one - fixed all my probs 
worth asking around on nutz for a spare if you're trying to save the pennies, as quite a lot upgrade to ali rads. or if you're not saving the pennies, why not use this opportunity to upgrade it yourself!
worth asking around on nutz for a spare if you're trying to save the pennies, as quite a lot upgrade to ali rads. or if you're not saving the pennies, why not use this opportunity to upgrade it yourself!
We had an overheating problem with my wife's recently acquired 10th anniversary model. It ran hot in slow traffic with the temp needle moving over to the right on "H" and would boil the coolant in the expansion tank.
A flush and new 'stat didn't cure it, but a new radiator cap looks to have done so.
A flush and new 'stat didn't cure it, but a new radiator cap looks to have done so.
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