Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
[Engine] Driving without a thermostat ... any side effects?
#1
Hi all. 

As a new, first-time-ever Multispace owner (2003 1.4 petrol model, very basic, no aircon) and new to the forum too, I'm grateful for all the info I've found here so far.

Less than 10 days into ownership, the car overheated, on one of the hottest days of the year as well. Beep + STOP warning. I stopped as quick as possible. Temp gauge was in the red. Thermostat failed apparently and one of the heater pipes split, loosing all the coolant. Had to get it towed away.

Next day a mechanic by-passed the heater altogether and joined the two heater hoses together. He also removed the thermostat and replaced the housing. He put water in the expansion tank and suggested using it like this for a while, to see if any further damage would show up, like head gasket damage symptoms I reckon. I was assured I wouldn't have an overheating problem anyway.

All was well for a week or so of short-trip local driving only. Got confident then and ventured a bit further onto open road. Hadn't gone far when I heard that beep again and STOP warning  – the temperature needle seemed to 'flick' into the red rather than creep up slowly, or quickly. I pulled over, turned off the engine and could hear the fan still working for a while afterwards. After it cooled down a bit, I checked the coolant/water level and it was ok this time. Temperature eventually read normal and I drove it home.

Brought it back to the same guy a day or two later and he checked the water was circulating ok, the pressure on hoses etc. Said he could find nothing amiss. The rad was even in temperature too, from top to bottom, suggesting no sign of a blockage I presume. There was no sign of oil in the coolant either, which was reassuring. So, we decided I should go ahead and buy the hoses and a new thermostat. Feeling relieved to have escaped a head gasket replacement, this didn't seem too bad. But ...

.. later than evening, just after starting up the engine, the engine management light came on, and it stayed on, for a whole 4 mile trip.
Got it read next day and it was giving codes for a faulty temperature sensor and also a lambda sensor.
Jeez! what next? Huh

I'm slowly getting quite depressed with this scenario ... and spending far too many hours reading, because I have very limited knowledge of car stuff, so far. None of these mechanical people I came across mentioned to me that you can actually check the health of a sensor, for example, with a volt metre or multimetre or whatever they are called.

So my questions are: Is it ok driving without a thermostat? Even for a while. Are there any side-effects?
Is there some domino effect going on here?
What about two sensors failing at the same time, is that unusual? Or perhaps they're not faulty at all? Although the temperature sensor fault makes some sense as it could explain the second mystery overheating. Buy why now?

Any help or suggestions very welcome.

Thanks in advance. I want to keep liking this car Smile
Reply
#2
A coolant temp sensor is surely pretty cheap? Suggest just change it.

https://www.berlingoforum.com/thread-8044.html

Removing thermostat means the engine will take longer to warm up, more emmisions, more wear. Not really a problem as a very temporary fix. But a thermostat is like £10!
Reply
#3
Agree with jamesg. Engine never gets to or stays at the optimum temperature without a stat and should only be a short term fix. The heater system is actually part of the cooling system as it is operational at all times - air is diverted towards or away from heater matrix dependent on where the temp control is set. So by-passing the heater is not a good thing to do as it reduces the cooling capacity available. Did the heater have a leak of some sort - usually accompanied by a spicy smell in the cabin when hot.
If the mechanic didn't take the time to fill and bleed the system correctly it will have air locks and these will again cause overheating. If you are adding anti-freeze then it would be false economy not to fit the correct thermostat ( there are a number of different ones) a new sensor, re-connect the heater and bleed the system. Maybe a different garage?
Reply
#4
Depending on engine cooling system design ( water flow circuit ) running without a thermostat can indeed cause localised overheating of the cyinder head and or a couple of the barrels - long and short is potential for a blown gasket so don't underestimate the potential for a big bill.

Best to put back to standard and have peace of mind.
Reply
#5
I'd go for the 'failing to properly bleed' scenario too - he's likely left an air pocket in the system which would cause the symptoms you describe.

Ours has a really 'spicy' smell if you use the heater - my thoughts being that somebody had overheated the beast at some point and knackered it. We changed the coolant, bled the system properly ( search this forum for tips i.e. location of bleed screws and how to blow down the disconnected overflow pipe to push the coolant up into the bleeders) and, so far (2,000 miles later and 1200 of those towing a small caravan) nary a problem.

Have a go at bleeding the system properly and then give it another test run - you may find that all is well.

As also stated - no thermostat will mean that everything warms up slower, you will see a drop in fuel economy (maybe tiny) and you'll not get heat inside in the winter quickly - I'd chuck another one in there asap.
                                                                                                                                                     
Our car - 2008 1.6 HDi 92 Multispace. 152,000 miles + counting. 17,000 + miles in our care. 48.88 mpg ave in that time
Reply
#6
(06-07-2017, 07:13 PM)jamesg Wrote:  A coolant temp sensor is surely pretty cheap? Suggest just change it.

https://www.berlingoforum.com/thread-8044.html

Removing thermostat means the engine will take longer to warm up, more emmisions, more wear. Not really a problem as a very temporary fix. But a thermostat is like £10!

I couldn't really understand it myself, why the mechanic wouldn't just go ahead and put in a new thermostat when he was removing the old one anyway. I had no problem paying for it. Hoses were damaged too though and they're not so cheap.
I wasn't too happy with the idea of driving this way, despite being assured it was fine, so I used the car as little as possible since. Thermostat and hoses are ordered now though, plus the temp sensor.
Sensor wasn't an issue till a week later. That's why I was wondering if driving without the stat had any effect on causing the fault.

Sensor is close on 40 euro. All told, just over 100 euro plus whatever goes to the mechanic.
Lambda sensor was coming up as fault too, also a week later,  and I think they're expensive, but worth doing the smaller stuff first and see how it goes.
Cheers!
Reply
#7
(06-07-2017, 08:56 PM)oilyrag Wrote:  Agree with jamesg.  Engine never gets to or stays at the optimum temperature without a stat and should only be a short term fix. The heater system is actually part of the cooling system as it is operational at all times - air is diverted towards or away from heater matrix dependent on where the temp control is set. So by-passing the heater is not a good thing to do as it reduces the cooling capacity available. Did the heater have a leak of some sort - usually accompanied by a spicy smell in the cabin when hot.
If the mechanic didn't take the time to fill and bleed the system correctly it will have air locks and these will again cause overheating. If you are adding anti-freeze then it would be false economy not to fit the correct thermostat ( there are a number of different ones) a new sensor, re-connect the heater and bleed the system.  Maybe a different garage?

I think the heater was fine. Only had the car a little over a week and the weather was hot at the time, so didn't use the heater, but had tried it out. There's no coolant in the system at the moment, just water. I was reading the Haynes manual pdf that someone posted here and thought to bleed it myself as it sounds like it's necessary in light of what happened, especially as the thermostat is already out. Haynes suggests removing it anyway to flush out the engine after flushing the rad.
Spent all I had on the car, expecting to be trouble free for a while at least, then tax on top of it, so I'm just going to have to learn how to do a few things myself. Just have enough cash to get the other parts but I'm hope the lambda sensor fault was a false reading. Somehow.
Reply
#8
(06-07-2017, 09:05 PM)geoff Wrote:  Depending on engine cooling system design ( water flow circuit ) running without a thermostat can indeed cause localised overheating of the cyinder head and or a couple of the barrels - long and short is potential for a blown gasket so don't underestimate the potential for a big bill.

Best to put back to standard and have peace of mind.

Yeah, my gut was telling me it wasn't a good idea. Especially as I probably narrowly avoided the blown head gasket with the first overheating. It would be a shame to cause it over a small part like a thermostat.
Reply
#9
(06-07-2017, 09:22 PM)GraemeT Wrote:  I'd go for the 'failing to properly bleed' scenario too - he's likely left an air pocket in the system which would cause the symptoms you describe.

Ours has a really 'spicy' smell if you use the heater - my thoughts being that somebody had overheated the beast at some point and knackered it. We changed the coolant, bled the system properly ( search this forum for tips i.e. location of bleed screws and how to blow down the disconnected overflow pipe to push the coolant up into the bleeders) and, so far (2,000 miles later and 1200 of those towing a small caravan) nary a problem.

Have a go at bleeding the system properly and then give it another test run - you may find that all is well.

As also stated - no thermostat will mean that everything warms up slower, you will see a drop in fuel economy (maybe tiny) and you'll not get heat inside in the winter quickly - I'd chuck another one in there asap.

Going to try the bleeding ... sounds like it worked wonders for yours. I don't think it was done. In fact I'm fairly sure it wasn't.
Have ordered the thermostat and hoses and they're going in as soon as possible, but there's also the engine management light which is now on constantly.
2 sensors faulty apparently. The cooling sensor and the lambda sensor.
Odd that 2 should go bad at the same time? I'm wondering if it's anything to do with the current set-up at all. Or just coincidence and bad luck.
I'll change the first one but I'm hoping the second one will be just be nice and sort itself out. Might be hoping for too much there tho'.
Reply
#10
Thanks to everyone so far for helpful advice and links etc. I'm new to using forums, so if I'm making a bags of anything, feel free to let me know. I'll cop on to it eventually anyway I reckon. I hope..

I see my status has changed already from being a newbie to 'it's starting to get serious'. That's funny.
Damn right it is too!
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)
[-]
Welcome
You have to register before you can post on our site.

Username:
  

Password:
  




[-]
Search
(Advanced Search)

[-]
Latest Threads
Big miles on an auto!??
Last Post: manovilla
Today 07:26 AM
» Replies: 23
» Views: 3086
Highest mileage Berlingos
Last Post: manovilla
Today 07:23 AM
» Replies: 29
» Views: 8607
New Vauxhall (Berlingo)
Last Post: manovilla
Today 07:20 AM
» Replies: 11
» Views: 951
What Reg Berlingo do you own?
Last Post: manovilla
Today 07:17 AM
» Replies: 128
» Views: 83836
gear leaver and rod needed
Last Post: landcrab
Yesterday 11:01 PM
» Replies: 2
» Views: 200
reversing mirrors
Last Post: GraemeT
Yesterday 10:16 PM
» Replies: 1
» Views: 295
1.6 hdi turbo fail again advice please
Last Post: Lighty
Yesterday 06:19 AM
» Replies: 22
» Views: 3366
gearbox removal
Last Post: Art b
09-12-2018 11:27 PM
» Replies: 2
» Views: 310
Issue with starts (cold/warm engine)
Last Post: TessG
09-12-2018 06:12 PM
» Replies: 16
» Views: 1359
Berlingo sudden lurching and jumping.
Last Post: lien
09-12-2018 04:31 PM
» Replies: 7
» Views: 1046

[-]
Recent Visitors
Locations of visitors to this page