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Vito 112CDi
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Discussion Starter · #1 · (Edited)
Hello All

I have looked through many threads but did not find this. I do hope thats because noone has experienced this, but hopefully someone knows the "fix" ?

112CDI '99

had the 60 degree C issue - changed the thermostat like 3 month ago, fixed it - engine ran just over 80 degree -nice.

But now the engine takes a very long time to heat up and it usually continues to way over 100c and I have no heat in the cabin, but when the system is "up and running " after maybe10-15 minutes suddenly the temp. drops significantly - below or about 40c - and I have heat in the cabin - but only for a short while - because the heat comes up again 100c + and I have no heat in the cabin - drops suddenly, I have heat .. . cycle takes about 2 min. and it just continues . . . .I should mention the " LOW coolant lamp " will follow the cycle after a little while, if I have just topped up the coolant.

I guess theres something stopping the coolant from getting out of the engine into the cabin heater and the rest of the system, then opens = the temp drops and there's heat, but then it blocks again ?
what makes it open at 100c + and why does it get stuck again ?

I'll add that the engine uses coolant fast when this behavior is active, but when I stop the engine and let it cool for 8 hours the system is still under a lot of pressure if/when I remove the expansion cap ? and not a drop under the car !
This is also the case if I try to open the cap while the engine is hot and the " LOW coolant lamp " is on ? coolant will be pressed out ? The system is pressurised - I mean.

I cooked my earlier defect thermostat to check function and it seemed to open and close correct, so I changed it.
That gave somekind of a confusing result ; first it like stabilized around 60c as usual and I had heat in the cabin, but then it like reset and it behaved the same as described above ?

Is there another thermostat for the cabin heat ?:confused:

I hope someone has an idea about this ! as it is confusing me, you can probably deduct that from the above description :surrender:

thanx
benny
 

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Vito 280 ,ZX7r,gsxr 750, ,Z650 Cafe ,Benelli Tornado.Ford consul , Ford Pop , ,Chevy Astro,Dog,Wife
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Sounds like you just have air in the system..
 

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Vito 112CDi
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Discussion Starter · #3 ·
Hi Gixxer

Yes, I thought about that and have tried everything I can come up with, to bleed the system and I believe I have tried all suggestions found in here, unless there is some way to bleed around the heater element in the cabin I can not come up with any new ideas in that respect.

How would you fill up an empty system ?

Thanx
Benny
 

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Vito 112CDi
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Discussion Starter · #4 · (Edited)
Hello All

Though i value gixxers reply ( honestly :) it's good to feel noticed :)

Does no one else have any ideas ? it's WE now and I have time to fix and test - I will anyway, but if someone could point me in the right direction - it would be highly appreciated.

Maybe I'm not clear enough in my description ? I certainly find it hard to describe, so that may very well be the case, pls. tell me !

Have a nice WE all !
 

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2000 Vito 110CDI (never should have sold it), Current project 1999 V220 Ambient
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As far as I remember there is a bleed screw on top of the pipe that feeds the heater matrix. I would agree with Gixxer that it sounds exactly like an airlock in the cooling system
 

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I have just done a trip and the same problem has come up . the car has not used a drop of water in 5 years and over the last 3 weeks it has been using water and on this trip it has been over heating as vito-cdi has explained . I have checked the water pump . checked the radiator and am now pulling the thermostate out to check that .

There must be some one out there that know whats what . Thanks
 

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I have just replaced thermostate and taken the car for a run . Every thing sorted . The thermstate was faulty . I can breath again .
 
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