C180 Coolant leak when vehicle left
Discussion
I wonder if you can help me on a coolant leak that has me stumped.
Car is a 1995 C180 WDB2020186F209260
The car leaks the coolant from the reservoir tank when it hasn’t been used in a few days. This isn’t a slow drip over the course of a week rather I come out in the morning and the workshop floor is wet where it’s seemingly lost the coolant suddenly. It’s wet around the hose where the reservoir tank enters the rad. The first time this happened I thought maybe it slightly blew a hose as it was very hot here in Thailand at the time. I removed both the hoses from the expansion tank and the lower radiator hose which is below it. I did this only at the radiator end.
I then refilled the system using 50/50 mix of coolant and distilled water and ran it for 15 minutes or so with the cap off. I had the heater set to full and the hose leading to the heater core (I presume) was hot but no hot air came through the cabin, only cold aircon air. I also did not undo the bleed screw on the thermostat which I’ve since read about!
I then took the vehicle out for a good drive and it warmed up / maintained temp fine and for the next couple of weeks whilst in daily use was good. I kept checking level in the tank and left the sump guard metal plate off of so any leaks would show up on the floor. None did so I assumed it fixed and one of the hoses had come lose.
Alas not, the car hasn’t been used in a few days and I come out to find a pool of coolant around the right front wheel and a dry reservoir tank. I had a quick look at the hose from the tank to where it enters the rad and sure enough it is wet in that area. It’s like someone comes and undoes the hose and nips it back up when its not in use for a few days! In use she is fine.
Any ideas fellas?
Could it be reservoir cap?
I bough a cheap fan clutch spanner but whilst it fitted the fan nut good the spanner broke before it loosened the nut (yes I know left hand thread) So I can’t get the fan off to remove the fan shroud and get a better look / remove the rad from the car – unless it can come out underneath the vehicle.
It’s just strange that it doesn’t leak while running or overnight straight away after its been refilled, rather a week of no use and it leaks. Never had that before.
What would you guys check next? I’ll be able to have a good go at it this weekend and need to get it fixed, it is annoying me!
Car is a 1995 C180 WDB2020186F209260
The car leaks the coolant from the reservoir tank when it hasn’t been used in a few days. This isn’t a slow drip over the course of a week rather I come out in the morning and the workshop floor is wet where it’s seemingly lost the coolant suddenly. It’s wet around the hose where the reservoir tank enters the rad. The first time this happened I thought maybe it slightly blew a hose as it was very hot here in Thailand at the time. I removed both the hoses from the expansion tank and the lower radiator hose which is below it. I did this only at the radiator end.
I then refilled the system using 50/50 mix of coolant and distilled water and ran it for 15 minutes or so with the cap off. I had the heater set to full and the hose leading to the heater core (I presume) was hot but no hot air came through the cabin, only cold aircon air. I also did not undo the bleed screw on the thermostat which I’ve since read about!
I then took the vehicle out for a good drive and it warmed up / maintained temp fine and for the next couple of weeks whilst in daily use was good. I kept checking level in the tank and left the sump guard metal plate off of so any leaks would show up on the floor. None did so I assumed it fixed and one of the hoses had come lose.
Alas not, the car hasn’t been used in a few days and I come out to find a pool of coolant around the right front wheel and a dry reservoir tank. I had a quick look at the hose from the tank to where it enters the rad and sure enough it is wet in that area. It’s like someone comes and undoes the hose and nips it back up when its not in use for a few days! In use she is fine.
Any ideas fellas?
Could it be reservoir cap?
I bough a cheap fan clutch spanner but whilst it fitted the fan nut good the spanner broke before it loosened the nut (yes I know left hand thread) So I can’t get the fan off to remove the fan shroud and get a better look / remove the rad from the car – unless it can come out underneath the vehicle.
It’s just strange that it doesn’t leak while running or overnight straight away after its been refilled, rather a week of no use and it leaks. Never had that before.
What would you guys check next? I’ll be able to have a good go at it this weekend and need to get it fixed, it is annoying me!
Is it a pressurised reservoir or an overflow/siphon back type?
Could it just be a slow leak that doesn't show up until it's been sitting a while. If you're driving around it could be dripping and drying up with air circulating (especially warm tropical air) and then sits in a cooler workshop and forms a pool.
If the hoses seem OK look for a crack in the plastic of the reservoir.
Could it just be a slow leak that doesn't show up until it's been sitting a while. If you're driving around it could be dripping and drying up with air circulating (especially warm tropical air) and then sits in a cooler workshop and forms a pool.
If the hoses seem OK look for a crack in the plastic of the reservoir.
Strange behaviour. The only thing I can think of that would leak after such a long delay is an air leak exposed when something has dried out - the system could be sitting under a slight vacuum when it's cold, which might be enough to prevent a leak. That theory relies on there being two quite unusual faults so it doesn't sound at all likely, but it's my only idea.
I'm pretty sure now that it is a hairline crack in the plastic end cap of the radiator that sometimes let's the coolant out. Werid I know but that's where I am with it.
I failed to undo the fan nut using the rachet strap method, the bloody strap snapped before the bolt let go. That bolt was extremely tight.
In the end took it to a local garage and with some acting skills and difficulty we managed to losen it and nip it back up to a tightness I can deal with at home here.
He had a pressure but it didn't seem to work, he also got it up on the ramps and we couldn't see anything obvious.
Topped up and isn't leaking yet, if it does it again I'll have to fork out for a new rad.
Any experience with Nessens?
I failed to undo the fan nut using the rachet strap method, the bloody strap snapped before the bolt let go. That bolt was extremely tight.
In the end took it to a local garage and with some acting skills and difficulty we managed to losen it and nip it back up to a tightness I can deal with at home here.
He had a pressure but it didn't seem to work, he also got it up on the ramps and we couldn't see anything obvious.
Topped up and isn't leaking yet, if it does it again I'll have to fork out for a new rad.
Any experience with Nessens?
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