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JCW GarageInterested in John Cooper Works (JCW) parts for your 1st Generation MINI? This is where JCW upgrades and accessories for the Cooper (R50), Cabrio (R52), and Cooper S (R53) MINIs are discussed.
I'm losing 3/4 cup of coolant (maybe less) each day (60+ miles), and seeing a trail of dried coolant coming from the driver's side, above the trans somewhere. There are splash marks above the starter, so I have a hunch it might be the housing or thermostat or adjacent hoses. Can you help confirm just by looking at the photo? If so, what hoses do I need to purchase? And is the thermostat part of the housing? Thanks so much guys!
Thanks guys - the fluid seems like is pooling on the transmission housing. And I can definitely hear a hissing in that general area upon engine shutdown.
UPDATE: Replaced the thermostat housing (a technically easy job, but made too complicated by the confined spaces and limited visibility); hoses did not need to be replaced. I bled the system and over 1.5 days had to top it up probably 0.5 cups a couple more times. The coolant level held steady for another 1.5 days... until today. I was backing into the driveway when I saw a long wet trail on the surface I had parked and I went, "Oh crap, what now?" Checked the expansion tank - it was below the minimum level. I'm waiting for the day to warm up a little before I check underneath, but I really hope it's not a leaky water pump now. It's odd (as you can see from the photo above) that the leak was coming from the thermostat area. But what I am saying? This is an R56, so it SHOULDN'T be odd. This could possible get from feeling frustrated (with the thermostat) to pissed off.
So I removed the air box/intake and tried to wiggle the water pump return pipe (from thermostat) and couldn't feel or hear any creaking/cracking that might indicate a cracked or broken seal on the WP end; it's not scientific, but I thought I'd give that a try. Checked underneath and it was WET down there, which makes it hard to tell if it's actually the water pump leaking or the seal where the pipe (from thermostat) plugs into the WP. Would really appreciate y'all's input. I have another observation: The expansion tank was pretty much empty from the time I noticed (in my last post) that the coolant was right below the minimum level indicator to the point when I did my latest inspection, which was roughly 1 hour later - do WPs leak that quickly? Or could it be indicative of a crack in the pipe?
It’s probably a good idea to just replace that pipe on “just in case....better safe...) premise. I just did my thermostat and that pipe broke off at the water pump end because it was 6 years old and brittle. Be smarter than me and have one on hand before you begin, it seems that these get very brittle and most folks end up needing to replace it too. I know that Way from WMW replaces them at the same time as a matter of course because of this. The o-ring just slips into the pump side with a little clip on the t-stat side. Takeoff the intake makes it a LOT easier, trust me on this.
Edit: just saw that you already did the thermostat replacement, you may need to pull it loose to replace that water pipe to the pump, but I’ll bet that’s your culprit
It’s probably a good idea to just replace that pipe on “just in case....better safe...) premise. I just did my thermostat and that pipe broke off at the water pump end because it was 6 years old and brittle. Be smarter than me and have one on hand before you begin, it seems that these get very brittle and most folks end up needing to replace it too. I know that Way from WMW replaces them at the same time as a matter of course because of this. The o-ring just slips into the pump side with a little clip on the t-stat side. Takeoff the intake makes it a LOT easier, trust me on this.
By intake, you mean intake manifold? That means I'll need a new gasket and all, right? The removal guide (Pelican Parts, I think) looks pretty involved, similar to removing the thermostat.
I would get the pipe done also. I have seen and done the thermostat and the pipe was fine. Its that end of the pipe into near the waterpump side that can crack when the thermostat is moved. It get the heat cycle then it get brittle over time. Most of the time its the little clip thats missing or not one and the oring is note seated into that thermostat.
I have the pipe. I had it all along when I did the thermostat, but I chose not to do it, because it felt fine. In hindsight, I should've just pulled it out and checked. Question for all of you: If the ends break off in the WP housing, can it be easily removed from there?
Now I"m just waiting... Just ordered hose clamp pliers from Amazon.
Yes the manifold. It’s really pretty simple to take off. There are only 5 nuts and one bolt underneath on the support bracket, easy to find when you remove the charge pipe. No need to replace the gaskets if they are in good shape, you can use a little RTV sealer if it makes you feel better, won’t hurt.
I have the pipe. I had it all along when I did the thermostat, but I chose not to do it, because it felt fine. In hindsight, I should've just pulled it out and checked. Question for all of you: If the ends break off in the WP housing, can it be easily removed from there?
Now I"m just waiting... Just ordered hose clamp pliers from Amazon.
yeah, I just used a pick and a flat head screwdriver to pop the broken piece out.... I recommend using a mirror or something to make sure you get it all out.
I have the pipe. I had it all along when I did the thermostat, but I chose not to do it, because it felt fine. In hindsight, I should've just pulled it out and checked. Question for all of you: If the ends break off in the WP housing, can it be easily removed from there?
Now I"m just waiting... Just ordered hose clamp pliers from Amazon.
Yes, just have to wiggle it out and clean up the cracked off pieces if it does.
Thanks everyone! I'm really hoping it's just the pipe and not the WP. I'm quite certain that it's the former as the amount of fluid loss overnight (whole expansion tank) is more in line with a crack. I think.
From what you have said, and my newly found intimate knowledge of the cooling system (had the ultimate nightmare scenario last week. I had to remove and flush every. single. hose and part that could be removed and flush the block and head due to a stupid decision on my part) it sounds and looks like the pipe is your culprit
