Technical Broken thermostat - Is it difficult to change?

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Technical Broken thermostat - Is it difficult to change?

Hey Brian. Don't know what to say now, you should go to a service if someone doesn't have any other ideas. After a 20 min run, the engine should be warm enough even with a broken thermostat. Regarding the temp indicator, the sensor from which he gets the signal its a new one, he came with the new thermostat and if the wiring is ok, it may be faulty, presuming that it worked after you installed the new thermostat and temp sensor. When I bought the new thermostat it came with a new temp sensor. The thermostat was from Wahler.
 
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Pardon me for butting in:eek:.
I have just been on the Eurocarparts site and just out interest I had a look at there types of thermostat.
I noticed that there are one big hose connection and two smaller ones , is it possible that you have got these the wrong way round and generated a Suck v Blow situation?

Not impuning your working practices or owt! but iv`e bored folks to death before about checking the simple things first!

In the past I have had to blush so much with wasting money on car DIY that the quack thought I had bloodpressure:D
 
Hi found this Termostat JTD / Thermostat JTD - cheap replacement / Termostato JTD - sostituzione a basso costo - YouTube on you tube
I think my thermostat is on the blink I will give it a go.

I did that once on my old 2.0 16v gasoline Croma and it was a very bad ideea. After few hundred miles, the not recommended thermostat got stuck on close and my engine was damaged. Lesson learned, I'll never do it again. I'm not saying it will happen the same for you, but I'm not saying that it can't either, but your 30 quid of economy could lead to some big expenses on the long run. I'd buy the necessary part if I were you, is not even expensive. If you want to do this trick for a thermostat, then what you would do if your turbo fails, which is 20 times more expensive ?! This without taking in consideration that you need to dismantle half of the car :)
 
Hello again the reason that the you tube interested me was that it would avoid me having to cry whilst dealing with yet another Croma problem and it did look an elegant fix I thought that it fitted in the large flow hose from the broken stat to the radiator and was original fit to a number of old renaults/volvo 360 so a quality part should be as likely to fail as the original, it would open at 89degc instead 88deg c emm and I suppose if next summer if it's flow rate is an issue it would not take much to get it out. I will check that it is the flow pipe to the radiator .
 
Thanks again all for the thoughts and comments.

Given the way it's connected to the heat exchanger I'm not sure it could be fitted the wrong way round, although if it was possible I probably would ;)

The strange thing is that it did work fine for a few weeks with the needle going up to the middle quite quickly and staying there. However now it's gone back to the way it was before I changed it.

It does feel as if it's broken as well although it does seem like a real coincedence that it stopped working the weekend I was taking the front end off to change the nearside headlight. Not that I was anywhere near the thermostat. Also, the engine hasn't lost any coolant at all since I fitted the new stat so I'm fairly confident there isn't a leak anywhere.

I guess I'll lodge a warranty claim with ECP and see how it goes - hopefully they won't make me return this part before they send out the replacement.

Not the easiest of jobs but at least I know where all the bolts are and what tools I need. Maybe I'll be really flash and make a youtube video this time :)
 
It might be nice to somehow get a measurement of the engine temperature. I'd suspect the engine is hot but the gauge isn't working.

Stuck at the left says the needle's dead to my mind - even when my thermostat was knackered it would still have a bit of a wiggle now and then, especially if driving hard at low-ish speed.

It might be interesting to see what EcuScan says the temperature is. It would be obvious if the sensor was working and the gauge not, as you'd have a discrepancy. However, it would also tell you if the sensor was not working - if the engine was genuinely cold then it would give a reading of a low temperature. If it's dead or disconnected then it would be a flat zero.

There's always the possibility it's just a wild coincidence and something has happened to break at the same time as you doing the headlight.

Also: when my thermostat was knackered and permanently cold it sounded cold all the time - like a rattly bag of spanners. Does yours smooth out and lose the rattle in the engine tone after 10 minutes? If so then it's hot. Hopefully you know what I mean - my other half's said ours sounds like an old banger when it's cold.
 
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Hadn't thought about ecuscan, I'll give it a go tomorrow. The engine doesn't sound too bad so maybe it is just the sensor. Fingers crossed.
 
Ok, this is an old thread but having just replaced the thermostat TWICE within a week I'll feel fairly experienced at doing this job?

I'll explain twice at the end but till then points to note are:

o To drain system you have to take main under tray off AND the small front black section linking to the from bumper. This section has screws and 4 "plunger rivets". You have to remove this to get to the radiator drain tap on the lower RHS.

o Battery & batter box have to come out as well as the turbo intercooler to inlet oxbow air hose (humped/bent hose)

o If you are careful there is no need to disturb the intercooler heat exchanger connections

o On the bottom back corner of the thermostat is a stud with a M10 nut which secures two water pipes. Take this nut off.

o Lift the front edge of the water header tank up and extract from securing bracket

o Back to the small metal pipes. Follow the outer RHS black pipe past the thermostat towards the front of the car up to the cylinder head. Remove the M10 bolt securing it to the front of the cyl. head. You can now move the outer pipe to the side. The inner pipe (stainless/silver?) is a little more difficult to unship from the stud. Gentle levering and a little bending of the "braket/tab" is required but once free pipe can be moved down.

o Hoses. There are 4. Three at back of thermostat (1 small, 2 medium) and one large at front. If you have the proper "Hose Pliers" you can remove AND replace the clips on these three hoses. However the big front hose is a remove/destroy and replace job.

o If you have hose pliers then the rear two larger hose clips should be easily remove. The smaller 10mm hose clip access may be obscured by the temperature sensor so you can just remove the sensor to get better access/aspect/approach angle.

o This smaller 10mm hose travels upwards to a pipe across the top of the cylinder head which is secured by three 10mm bolts. I suggest you release these as well to give more play.

o There is also a crankcase recovery tube, next to the oil filler cap. Suggest you unship this as well.

o Finally you may find it beneficial to uncouple the quick release vacuum hose that do to the brake master cylinder.

o The two M13 thermostat bolt can now be accessed with 1/4" drive 13mm sockets. 1/2" are too tight. If you have a good memory then visually note, or take a picture of the exact position of the thermostat before removing the bolts and extracting the thermostat. Spacing is tight, visibility restricted/narrow and thus accurate replacement is much more fiddly.

Right now for the IMPORTANT bit.

If you look at the original Fiat thermostat housing the "O" (actually square ring) sits in a groove and there are pips/clinch points to help retain the ring in the groove.

I used a GATES replacement that lacked these pips but the ring fitted snugly and looked secure and did not drop out.

When refitting the thermostat (on my own) I had several attempts to get the bolts & holes lined up. Eventually got there and then finger tightened the bolts before alternately 1/4 turn tightening down to "bight/stop" point. This is when I discovered/felt that the top bolt had become firm but the bottom wanted to accept more turns. Something didn't feel right but as we all know when you have struggled to where you are at backing out can be the last thing on your mind.

Anyway, torqued up to 2.5daNM (25NM), refilled, bled, test drove, checked bleed/topup etc. and all OK. Checked several days later to find header tank almost empty and fluid all over the top of the gearbox.

Fearing I may have crushed a slipped "O" ring I bought a complete new thermostat and then proceeded to strip down again. Yes the "O" ring had slipped by the smallest of distances. 95%+ was neatly in the grove but a 10% inner edge had been pinched and crushed thus affecting the overall seal quality.

Second time round I did the following.

1) put 6 small dops (with paper clip wire end) of super glue into the thermostat housing groove, fit "O" ring and then leave face down on flat sure under gentle pressure

2) get another pair of hands to help hold the hoses back, hold a mirror, etc. so you can directly align the thermostat without the need to slide around looking for the holes as this sliding/realignment process is most likely to disturb that pesky "O" ring.

Now I could have been unlucky with the first attempt but I have to say the wife's helping expert hands did a good job! :)
 
I cut a 13mm open spanner in half to make a stubby! I could not access the stud any
other way.(1.9 8v) and only one flat at a time!

The joys......

My local independent has threatened suicide if I ever bring my alternator to him again.

The joys.......
 
I cut a 13mm open spanner in half to make a stubby! I could not access the stud any
other way.(1.9 8v) and only one flat at a time!

The joys......

My local independent has threatened suicide if I ever bring my alternator to him again.

The joys.......

Thanks for the 8V vs 16V clarification. On the 16V if you removed all the stuff mentioned then 1/4" socket drive a 13mm allows access to the two thermostat housing bolts.
 
Hi it is some time since I uesd the youtube thermostat fix posted on this thread and it works fine even on the hotest of summer days aircon on stuck in traffic!.The temp needle rises to half way farly quickly never higher, a positive thing is that the engine is much quieter and smoother.I know that the sticklers might pour scorn on this fix but after 10,000 miles no problem and if it ever does stick shut it will take minuites to pull the stat out of the hose. Best of all for the 16v engine the stat in hose ploy takes less than an hour and no bad language or every tool in my shed.:)
 
Well some sticklers might actually agree with you provided we are talking about a duff thermostat that does not close down enough in cold weather, which is the majority / all? of Croma thermostat issues.

Were mine not a towing vehicle where I drag down to Italy and into the mountains as well a lakes areas (temperature, altitude, steep long haul climbs) I would certainly give the "in tube thermostat a try. It will however increase water flow resistance by virtue of two mechanical restrictions in the water flow path and in heavy load conditions (like towing up very long inclines at altitude) you won't know how much of a headroom margin there is till that needle unexpectedly goes beyond where you want it to.

That said for normal UK and European motoring I doubt the extra restriction is likely to cause an issue so for the less brave a quick to do thermostat implant is a good option, even for sticklers :)
 
I ended up borrowing a ratchet spanner to get the stud off my 8v 1.9d. The 2 other bolts hidden behind it are a serious pain to find never mind undo.
 
I keep on meaning to do some runs with MultiECUScan connected to see a graph etc. and actually find out what temeperature the first div down is. 5 degrees, 10 degrees .... below normal.

On a 16V Diesel the temp. is 80 degrees if the hand is on the vertical line on the gauge (normal working temp.)
When the hand comes free from the pin, the water is 50 degrees, on the line in between this positions it is 65. Measured with Ecuscan.
In the old days I was used to place a piece of carton in front of the radiator to raise the temp. This was not to forgotten when the ambient temp. went higher. (Dangerous!!!)
Sudden types of Mercedes were equipped with a adjustable curtain in front of the radiator, don't know if this was hand or automatic controlled.
 
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Sudden types of Mercedes were equipped with a adjustable curtain in front of the radiator, don't know if this was hand or automatic controlled.

The cheaper ones were just held in place by press studs and were adjusted manually. The deluxe version could be operated from inside the car. My old man had one on his Sunbeam Supreme for the German winters.
 
Hi it is some time since I uesd the youtube thermostat fix posted on this thread and it works fine even on the hotest of summer days aircon on stuck in traffic!.The temp needle rises to half way farly quickly never higher, a positive thing is that the engine is much quieter and smoother.I know that the sticklers might pour scorn on this fix but after 10,000 miles no problem and if it ever does stick shut it will take minuites to pull the stat out of the hose. Best of all for the 16v engine the stat in hose ploy takes less than an hour and no bad language or every tool in my shed.:)

Dear Telegraph, sorry for so much questions about the inline thermostat you installed, I like to use it as a tester to find out if the original stat is responsible for the degrease of temperature on low speeds. Please let me know, is this thermostat identical to the one showed in the video, namely Calor Stat. TH4493.89? If not please tell me which one you made use of. Is the needle on the temp. gauge stil in vertical position, spot on the line when on temperature, since this thermostat is developed for 89 degrees. Can you please explain where exactly you placed this apparatus?
Many thanks in advance
 
Hi Vento yes pretty sure that is what I used it fits old Volvo 360 and some other cars. It fits into the large rubber hose from the thermostat housing to the radiator to the left of the battery. It involves removing the hose clamp and pulling the hose off then the only tricky part pushing the stat into the hose the YouTube bloke used grease to help I used neat antifreeze as a lubricant and it is a tight fit a tube or large deep socket helps to push it that last 25mm be careful not to damage the bulb thing. As you refit the hose you will see that the bulb fits nicely into the housing, new clip refill and hopefully job done
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.Ours is still fine last summer on our holidays it had a stiff test and no trace of overheat. The temp needle should rise to halfway fairly quickly even when it's freezing. I do not understand why FIAT fitted this over complex difficult to access expensive and unreliable thermostat assembly so many thanks to youtube gentleman!.
http://www.ebay.co.uk/itm/VOLVO-340...ts_SM&fits=Car+Make:Volvo&hash=item461b16fc41
 
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