A little more news about the bimetal. G.RAU have confirmed that both the TB1577-AGE and -GE are indeed manufactured by them and that the TB1577-AGE is designed to meet DIN1715 TB1577A specifications.

However G.RAU mentioned that the TB1577-GE cross references to their part TB1577B-GE which sounds a little strange to me. I'm awaiting confirmation.

I'll attempt to download a copy of DIN 1715 again, but I'm struggling finding a freebie as I don't really want to spend out 60USD

Lea

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

I received confirmation by G.RAU that their bimetals marked TB1577GE are crossed referenced to DIN 1715 TB1577B.

However we still have no full standard to review the Coefficient of Expansion (CoE) between the A and B specs - although I have found a snippet detailing some specs (in German), see attached. I can't quite understand the left hand column, is it saying that the meterial is different between the two? Is it a percentage/ratio of the composition?

G.RAU's product literature implies the only difference between A and B is simply the stress characteristics.... not the CoE ... interesting.....

I need to translate the DIN spec so another job for latter today...


I'll order my new VFC this weekend (hopefully) and of course will post any findings here too.....should anyone really care...

If the the new VFC allows the coolant to run at 110C as others then guess I'll have to send it back to Benz! I figure if I buy from my local dealer I won't have an issue resolving temperature issues should this be the case - but there is a reasonable price penalty of course!

Lea

Attached Thumbnails

 

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

Although the partial DIN 1715 spec I attached earlier is of poor visual quality, I really should have read it with a little more attention!

At the bottom, we can clearly see the metal composition between A and B is different (Kanthal specs also show this as 0.5Cu is added), however the specific deflection is identical at 15.5 for both. Also, compare this with both TB1577A/B products from Kanthal (155TB1577 and 155CTB1577), these have the a specific deflection of 15.6 each.

More to the point, my VFC has no A marking, G.RAU have confirmed that this indicates it's a B part and so we now know that A=B=15.5 specific deflection or TB1577A-GE = TB1577-GE.

So, one could conclude that although the alloy composition is different between A and B, the deflection is identical and therefore although my car has a different bms to others it's CoE is the SAME, contrary to what others have previously hypothesised!!

Therefore, when Mercedes changed from 119 200 00 22 to 119 200 01 22 on the 500E/E500 they did NOT change the bms because this wasn't required, they changed the airflow/temperature characteristics surrounding the VFC - or/and perhaps the internal characteristics of the VFC. Also, a few posts previous shows how the viscosity of the silicone fluid within the clutch can significantly change with temperature - bringing me back to my original thoughts of VFC fin and cowl design.

The VFC's locking point is NOT solely dependant on the bms, there are many factors significantly influencing this.

If I could get a reply from Sachs I would love to hear what the changes are between our VFCs and the 'Tropical' versions - because my bet would be no change in the bms..however they refuse to answer by email


Lea

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

Firstly, after picking up my cowl I soon realised that it couldn't be fitted as the plastic clips had all suffered and most had broken... I did try

Anyway, guess what I received and fitted today!? A brand new OE Benz 119 200 00 22.

Note that this unit's bms has the Horton part number 60 2100 013 001 but the SACHS stamp on the rear of the aluminium housing! I've not considered Horton before or how they fit within the dealer supplier relationship but the part number does seem to resemble the Sach's structure, although not directly listed by Sachs - I'll look into Horton later

So, moving on, here are a few pictures:



























Anyone for a closer look at the bms?




Let's start by observing the new VFC:

1. No MB part number on the bms.

2. Horton sticker on the bms

3. Dimensionally identical to my previous VFC

4. Sachs stamped on rear

5. 'Top' marking on the box

6. bms marked TB1577 A-GE-

7. bms looks slightly more 'yellow' than previous

8. Identical cowl design

9. New VFC has significantly less friction. Can spin the fan 1.5-2 turns by hand. My old VFC turned only 0.5 turn.


After some testing today I can report the following:

1. New VFC cuts in at a smidge over 95C, as displayed on my coolant gauge - previous VFC cut in at 85C.

2. Under my normal driving conditions (todays 18C ambient with a mixture of urban and light motorway) coolant temperature stabilised at 90C-95C, VFC NOT locked - perfect engine temperature!

3. I had trouble increasing the coolant temperature to 100C but today I also needed to check exhaust emissions so the cat required a pre-heat - this simply means driving hard in second gear for around 15 minutes . VFC cut in at 95C-98C and the roar was evident.

4. After cat pre-heat conditioning and back to idle, coolant temperature increased to 100C. Car was left idling (waiting for Emissions Inspector) for around 5 minutes. Coolant temperature stabilised at 100C. VFC could be heard switching in and out.


My thoughts:

The new VFC operates perfectly and exactly as described by the MB documentation - a little relief

It does however operate at a slightly higher temperature then my previous VFC, BUT, the previous VFC was refilled (volume was guessed) with an alternative silicone fluid and had no cowl fitted.

So, for now I conclude that for the R129 129.067 (Euro spec) M119.972 a VFC purchased from MB, part number 119.200.022, operates perfectly


Enjoy!

Lea

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

i think the sticker says norton as in the abrasive company.not sure if that matters, though.

__________________
'95 s500 (bought for wife but can't bear to share!!!) 125kms
'92 legend 180kms
'88 tbirdturbo(fantastic car-only regular maint.)120kms
'87 mustang gt(gone)
'86 tbirdturbo(gone)
'85 mustang gt(gone-but not forgotten)

Lea,

Glad to hear that all ended up well. I never did have any doubt that once you change out your VFC, your coolant temperature will than be back to normal.

I am not clear however as to whether or not you received the newly redesigned VFC or the original design VFC. I will also be extremely interested in knowing whether or not your new bms has the identical bending characteristics as the original bms.

Phil

__________________
'95 E300 Diesel, 264,000 Miles. [Sold it]

Hi daddiojiggy

From the images the sticker looks a little like Norton but I studied it closely and it's definitely Horton - the H is just a funny font that doesn't .jpg very well when using 30% compression.

Take a look at their web site and you'll see Horton is a VFC manufacturer too - although why they sell Sachs VFCs is a little of a mystery! Maybe they have some kind of relationship?

Hi Phil

Good to hear from you again. I have top say I was a little relieved but you I were pretty convinced that it would all be OK - although I paid a significant premium by going to my dealer for the sake of this thread and of course the returns policy.

Regarding the VFC, it's dimensionally identical to my previous unit. MB never carried out a redesign across the range, only for the 119.974/975 engine - the EPC clearly shows this coupled with the 974/975 notes made here way back. Also, by MB providing me a VFC with identical part number '00 22' and dimensions this again demonstrates that no such redesign was made across board. The VFC and cooling design works PERFECTLY in the R129 so no need for change!

According to G.RAU (the bms manufacturer) the bending characteristics (specific deflection) are identical between this 'TB1577 A-GE-' and my previous 'TB1577 -GE' but in the interests of science it would be interesting to repeat yours or Jim's experiments.

I still have my old bms should any one want to try - Jim?


Two things that now interest me:

1. Who and how Horton fit into the equation?
2. That by removing the old cowl/refilling the VFC the cut-in point of the old VFC was lowered to 85C and therefore in normal driving conditions the VFC operated quite regularly
3. The R129 cooling system is as thought, designed to run at 90-95C in most driving conditions and in-fact it's quite difficult to increase it to 100C.

For those W140 drivers suffering temperature issues maybe there's a design issue with the rad?


One thing I want to correct is the previously hypothesised:

This is NOT strictly true and has been proved, so for those with R129.067 M119.072 cars your new MB VFC will operate perfectly keeping your cooling system running at a maximum of 100C (under severe driving conditions) and at 90C-95C for the rest of the time.

(Assumptions made - Ambient 20C)


Lea

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

I new I'd seen the name Horton before...


Unfortunately this means we still can't identify the VFC Sachs PN as the last three digits on the Hoton sticker are 001! Although I'd put money on it being identical to the Sachs 031.

Lea

__________________
'93 R129 500SL-32
'89 190E 2.6 - sold in 2002

http://antron.pwp.blueyonder.co.uk/i...nature/Sig.jpg

Hi,
I have a 96 E230 W210. My car's temp was usually running at 95-100 even in cold weather. My mechanic said it was a faulty clutch fan.
I just went to an aftermarket Mercedes parts shop and sold me a TRUCKTEC visco fan which they claimned as a TROPICALIZED version. it is a replacement (made in Germany) part with a mercedes part number reference.
The part is cheap at around $92. The Sachs version was a lot more expensive.

Now, the car runs at 80-82 even in traffic with the A/C on.