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GoNz0

The old thermostat questions (again)

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I remember now when I did this mod to an old car, when it used to come up to temperature it would go beyond the opening temp as the hot coolant was nowhere near the bodged in stat so temp needle would shoot over close to overheating before it finally got the stat hot.

 

Anyway back to my patience trying once again stuck on the drive 5er.

 

Spoke to the guy heading up the UK side of Hella by pure luck when I phoned for tech support on this, It isn't a known fault but why would it be as 99.?% of owners don't check temps, BMW don't check temps, BMW do next to nothing unless a parts pissing out a fluid or hanging off the car. Diagnostics show no code for this.

 

It's only by pure luck I was pointed to the heat exchanger after changing both the other stats and after that it was only me pulling up the hidden menu to view temps after noticing the economy had taken a dive that I realised the new part had failed after a few weeks. Pure and utter shitty luck the new one died the 1st time it opened?

 

I have decided against buying from BMW as they have a 100% markup for the same part, this was confirmed again by Hella as being the same part they sell to BMW, minus the sticker and various details removed with a dremel on the other side to de-BMW it.

 

Anyway a video is below of my less than technical test  

 

https://youtu.be/KDX9WOxXhb8

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I collected heat exchanger #3 today, production date was 6 months newer than the previous one. Spent the usual few hours installing it, 20 minutes bleeding the coolant, the coolant that I got out was clear, no debris like last time. A 40 round trip back to euros to get the refund on it, temps were fine 87-89 on an urban run.

I took it out tonight once the roads were quiet and went for a long mixed drive, temps were solid averaging 88 with the gearbox oil around 55. A few miles from home I put it in manual in 3rd at 30 and did a few foot down up to 60 and back. A few minutes after that I noticed the temp was 82!!!!! :( and it dropped to 79 while I was doing 50, I carried on back to the bypass and launched up the slip road, temp hit 87 again, then stuck it in cruise at 75, temps dropped back to 79 again and only went up if I booted it.

Gutted is an understatement, I know the bastards stuck open again, I got home and had a feel around and sure enough the return pipe to the main stat was stone cold, the return pipe from the heat exchanger was hot again. The photo I took of the last one had a date of 04/17 and this was 11/17 so 7 months apart to hopefully rule out a bad batch but I really am at my wits end now, If I found shit in the coolant it could point to the water pump impeller breaking down if it was plastic or composite but the pics I see online all seem to be metal impellers?

 

I have been talking to the UK manager at Hella in charge of this part of Hella UK and he has confirmed they are the same units BMW buy, they butcher off the markings with a grinder and half of the sticker with BMW's part number on then stick an additional Hell/Behr sticker on, this rules out buying cheap shit!

 

I am at a loss now, I don't know why this keeps happening, the cars basically sat off the road again as the temps are low enough to screw up economy and prevent regens.

 

I am open to suggestions?

 

 

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Bloody hell..  I thought it was crap before, but that really does take the piss... Can't be three dodgy stats, can it?  You'd hope not, but then again, I guess you sort of hope it is!  

 

Maybe get your man at Hella to pick one out and give it a thorough test before wrapping it nicely and posting it to you?

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I got my temp display on on the way home from work tonight. 35 minute drive, 20 mins rural roads, 15 mins on the motorway.  Temp didn't go above 69, although it is blimmin cold out there tonight.. 

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Just now, DaveR said:

Bloody hell..  I thought it was crap before, but that really does take the piss... Can't be three dodgy stats, can it?  You'd hope not, but then again, I guess you sort of hope it is!  

 

Maybe get your man at Hella to pick one out and give it a thorough test before wrapping it nicely and posting it to you?

I asked him to find the one I returned and get me a report on why in the hope it's either the failsafe springs overpowering a bad batch of stats that are unable to close one opened or I would be happy to get a reply saying a lump of plastic water pump impellers stuck in it holding it open, but if it were the later I would have expected to find bits in the coolant I drained off.

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3 minutes ago, DaveR said:

I got my temp display on on the way home from work tonight. 35 minute drive, 20 mins rural roads, 15 mins on the motorway.  Temp didn't go above 69, although it is blimmin cold out there tonight.. 

Thing is Dave, when the systems working it gets to 88 (give or take a couple) and stays there, around town and motorway as I tested both, I did a driving miss daisy to ECP and back due to the time of day and the amount of cameras about. Its -1 round here and it was fine for about 90 minutes then went south again when the stat jammed open. Once I had given the box a workout in 3rd to warm up a bit more it started to cool the engine as you can see above. 

 

As for your 69c, it will over fuel and be unable to regen the DPF.

Edited by GoNz0

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1 minute ago, GoNz0 said:

Thing is Dave, when the systems working it gets to 88 (give or take a couple) and stays there, around town and motorway as I tested both, I did a driving miss daisy to ECP and back due to the time of day and the amount of cameras about. Its -1 round here and it was fine for about 90 minutes then went south again when the stat jammed open.

Appreciate that..  I said it more as a reminder to myself to look at my temps, but that'll have to wait til it's a bit warmer.  Buggered if I'm doing that in this weather. ..

 

Assuming the gearbox stat works like any other stat, then I guess the wax must have leaked out somehow? Maybe a bad crimp on the housing, or something.  

And I know you don't like the idea, and frankly, I don't blame you, but maybe the Renault in line stat is the answer....

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I had a similar issue with a driveshaft on a Honda once, replaced it with a "quality OEM" part and it was worse than before. Assumed I must have got something wrong. In the end decided the new part was faulty. Got it replaced. Better but still not right. Replaced it again and still a problem. Finally replaced it again with a part from a different supplier and perfect.

 

So.... in my case something had gone adrift in the manufacturing process at the part manufacturer. It does happen, and if Hella are manually grinding off markings that tells me their processes are manual and prone to errors. I also know that some automotive manufacturers do tier parts, BMW will get the very best and the parts market will get those that are not quite as good.

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Thanks Jason, I have heard of this before with the stats from BMW as well, pain in the arse, I guess I have to wait for Hella to reply now.

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I've heard this too guys...but it's sometimes worth the gamble. Especially if the company accepts the returns etc. However, I've finally got the EGR and main Stat replaced yesterday from Cotswold . Car now running at a solid 90 even at 1.C. A 50 mile run in manual 4th at 70 done too. Fault cleared manually by reader. So will see how it is on next run. I suspect it will need a few runs to regen as the cat was like this when I bought it. Silly me bought a coolant sensor first which I mis read on here. BMW Cotswold accepted it back but unfortunately my garage wants to charge for all labour costs. But cash is king and they like to negotiate.. 

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anyone got an old one who can pop the clip off the thermostat housing to look inside and put some pics up?

I would be it would involve draining the coolant again in that area and possibly having to remove it from the gearbox oil lines losing more oil :(

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1 minute ago, RightHandGoose said:

Feel for you..... time and money already spent surely must justify the part from BMW Cotswold with discount of course.... 

As the Hella manager has said it's the same part stumping up another £100 is a bitter pill to swallow :'(

I will see what they quote and may see if my local can price match to save fucking about with returns *sigh*

Edited by GoNz0

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Yeah I'm resigning myself to that fact now, at least I can go back to the parts dept if it happens again rather than messing about with CP4L and Euro's

To credit them they did arrange to get one of the last 2 they had transferred to my local branch but as you say this shouldn't happen, nevermind 3 times. They are showing out of stock again so I think I will start the ball rolling on the RMA.

 

Local nottingham branch has just quoted £210, RRP is £224.96

So £80 more than the debranded version!

 

Wife is going to murder me at this rate, I tried to get the gearbox fill plug out yesterday when the box was warm at least 30 degrees not the -1 it was outside and stripped the torx (I was using a decent halfords pro TX50 as well ffs)

I was booked into the garage anyway as I noticed a weep of fluid that sods law I cleaned off 10 minutes before they sent a message saying come in tomorrow so we can check so I have to go in cap in hand and hope he has an easy way to get the bleeding thing out (box will be warmer by then) and replace it. He is a ZF specialist on the 5er so I hope it's a 2 minute thing for him and a drink in his back pocket.

Edited by GoNz0

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5 minutes ago, JasonH said:

The gearbox fill plug is an 8mm hex.

 

Topping it off is relatively easy if you know what you're doing and have a ramp.

My box is a TX50

I can just jack the car enough to get under and have it level!

Edited by GoNz0

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Got told it was an 8mm so fuck knows how I missed that, cars on a ramp at rga in Notts, dropped the exhaust off and he got the plug out :)

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Well i pickup my genuine one from my local this afternoon who price matched my best offering.

Here we go again.

 

CP4L said I can take the latest duff one back to Euro's with my invoice and return number for a refund, at least I don't have to mess about waiting forever for that to be refunded like the 1st.

Edited by GoNz0

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