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Warm Up Regulator diy kit vs Pro refurb

Started by SteveDuNord, 24 June 2023, 03:55 PM

SteveDuNord

I can't find any information online as to why people choose an expensive exchange and refurbishment service over just buying your own repair kit.

Is there a truly expert knowledge or skill that goes along with fixing these properly, or are the diy repair kits missing certain parts only available to the pros?

I'd be happy to pay for a refurb but they take up to 5 weeks! Would be great to hear a definitive answer on this. And it could help others who search for the answer online.
Thanks.
'77 280se

rumb

To me the benfit of sending out FD and Wur together is that they come back bench tested and calibrated to your engine. Its plug and play and will work immedately.
'68 250S
'77 6.9 Euro
'91 300SE,
'98 SL500
'14 CLS550,
'16 AMG GTS

Randys01

If your question relates to just the WUR, then I too can see the attraction of doing it yourslef.
At one time there, I could fix one in an hour.
But I had my own test rig...and they are fiddly little brutes.

If the question refers to the fuel divider, this is a whole new ball game..give me the pro shop any time !!

.pay ya money..move on.!!

raueda1

Quote from: rumb on 24 June 2023, 04:43 PMTo me the benefit of sending out FD and Wur together is that they come back bench tested and calibrated to your engine. Its plug and play and will work immediately.
One hopes!!  I had a WUR come back from CIS that had cold pressure wildly off.  Happily it was easy enough to correct.  Maybe I was their one-in-one-thousand goof, but it was 100% of my CIS experience.  On another occasion I got a rebuilt WUR from a lesser firm than CIS on ebay and it wasn't set right either. I guess the take away is to test the pressures even if you go with a rebuilt unit, just to be sure.  Also, if you replace any of the primary pressure regulator o-rings it's very likely that you'll need to tweek the primary fuel pressure.  Cheers,
-Dave
Now:  1976 6.9 Euro, 2015 GL550
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

SteveDuNord

Well I've contacted 2 places and they both want 5 weeks to recondition my WUR so can only assume they do stringent tests. Or are busy.
'77 280se

Feather535

Quote from: SteveDuNord on 24 June 2023, 03:55 PMI can't find any information online as to why people choose an expensive exchange and refurbishment service over just buying your own repair kit.

Well, in my experience the pros who are set up to rebuild these units are able to do it better. 

I spent many ultimately fruitless hours trying to get the control pressures right on a 280 SE after throughly cleaning the WUR and replacing all the internal parts with new ones from a kit, but finally gave up and bought a remanufactured WUR from k-jet specialists in Australia.  With the reman unit installed, the CP was spot on immediately and the engine ran perfectly for the first time. 

In the time-money equation, I would have been better off buying a rebuilt WUR at the start.
--------
1977 280SE
1983 300D (sold)
1988 BMW 535is
1999 E320T (sold)
2009 E350T (wife's)

SteveDuNord

Quote from: Feather535 on 27 June 2023, 10:29 AM
Quote from: SteveDuNord on 24 June 2023, 03:55 PMI can't find any information online as to why people choose an expensive exchange and refurbishment service over just buying your own repair kit.

Well, in my experience the pros who are set up to rebuild these units are able to do it better. 

I spent many ultimately fruitless hours trying to get the control pressures right on a 280 SE after throughly cleaning the WUR and replacing all the internal parts with new ones from a kit, but finally gave up and bought a remanufactured WUR from k-jet specialists in Australia.  With the reman unit installed, the CP was spot on immediately and the engine ran perfectly for the first time. 

In the time-money equation, I would have been better off buying a rebuilt WUR at the start.

Thanks, I'd gathered as much reading your thread but good to see it confirmed.

I'm not looking forward to a 5 week wait but if it has to be done, so be it. I've just whipped my WUR off for the second time and it has some brown residue in it, which I'm assuming is dirty fuel. I'll blast the mesh filters again and see what gives before sending it off. The gasket looks worn out at the very least, which tempts me towards a kit - must resist!
'77 280se

raueda1

Quote from: SteveDuNord on 27 June 2023, 04:27 PM
Quote from: Feather535 on 27 June 2023, 10:29 AM
Quote from: SteveDuNord on 24 June 2023, 03:55 PMI can't find any information online as to why people choose an expensive exchange and refurbishment service over just buying your own repair kit.

Well, in my experience the pros who are set up to rebuild these units are able to do it better. 

I spent many ultimately fruitless hours trying to get the control pressures right on a 280 SE after throughly cleaning the WUR and replacing all the internal parts with new ones from a kit, but finally gave up and bought a remanufactured WUR from k-jet specialists in Australia.  With the reman unit installed, the CP was spot on immediately and the engine ran perfectly for the first time. 

In the time-money equation, I would have been better off buying a rebuilt WUR at the start.

Thanks, I'd gathered as much reading your thread but good to see it confirmed.

I'm not looking forward to a 5 week wait but if it has to be done, so be it. I've just whipped my WUR off for the second time and it has some brown residue in it, which I'm assuming is dirty fuel. I'll blast the mesh filters again and see what gives before sending it off. The gasket looks worn out at the very least, which tempts me towards a kit - must resist!
Sounds like a good plan.  That sludge is, as far as I know, very fine rust dust.  Feather had the same issue if I recall, and I have too.  Until the fuel system is purged of it, problems will recur as the various filters and screens get plugged up all over again.  It will make you crazy.  I'd change the primary fuel filter if you haven't already.  Then disconnect the fuel line and collect fuel in a clear container till there's no more junk in it.

As for the send-it-out-or-DIY question, I fall into the minority camp.  Try and rebuild IF you're willing to monkey with resetting it.  Why?   Just cause it's cheaper and faster.  And if you fail then just send it in.  Cheers,
-Dave
Now:  1976 6.9 Euro, 2015 GL550
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

SteveDuNord

I bought the rebuild kit.

From what I can tell, there's nothing you can't calibrate on the car itself that you can on a test rig.

It's just not that complex a unit.

The only thing that can stop me progressing is myself!

 :-[
'77 280se

Feather535

Quote from: SteveDuNord on 27 June 2023, 04:27 PMI've just whipped my WUR off for the second time and it has some brown residue in it,

That brown dust is your enemy. Like raueda1 says, it seems to be very fine rust particles.  Regardless of whether you send the WUR out or rebuild it yourself, you must rigorously clean everything upstream before you reinstall it or you'll be back where you started (ask me how I know).  At minimum, replace the screen in the inlet side of the fuel distributor, the main fuel filter, and the screen in the bottom of the fuel tank.  Better still, remove the tank and clean it and replace all the hoses at the rear of the car. 
--------
1977 280SE
1983 300D (sold)
1988 BMW 535is
1999 E320T (sold)
2009 E350T (wife's)

Feather535

Quote from: SteveDuNord on 28 June 2023, 02:32 PMFrom what I can tell, there's nothing you can't calibrate on the car itself that you can on a test rig.

That's true, but in my experience calibration isn't the problem: cleaning is.  I wasn't able to get adequate flow through the inlet side of the WUR even with multiple soaks in parts cleaner and lots of compressed air.  You may have better luck.  An ultrasonic cleaner would probably help.
--------
1977 280SE
1983 300D (sold)
1988 BMW 535is
1999 E320T (sold)
2009 E350T (wife's)

SteveDuNord

Yes the screen in the WUR is going to be a challenge. I'm hopeful, though, because the first time I only used contact cleaner. This time I'm going to soak the hell out of it with brake cleaner. I also noticed that the shiny, thin, disc is in fact two discs. Not sure why, seems to be a single piece in all the guides I've watched.

The gasket is clearly worn out. I'm hopeful new parts and a damn good soak will produce results.

I've changed the primary filter, the inlet filter and also put new o rings on the primary fuel regulator. The tank and strainer were seen to by the previous owner but could need doing again. I'm reluctant to tackle this on my driveway. But we'll see.
'77 280se

raueda1

Quote from: Feather535 on 28 June 2023, 10:09 PM
Quote from: SteveDuNord on 28 June 2023, 02:32 PMFrom what I can tell, there's nothing you can't calibrate on the car itself that you can on a test rig.

That's true, but in my experience calibration isn't the problem: cleaning is.  I wasn't able to get adequate flow through the inlet side of the WUR even with multiple soaks in parts cleaner and lots of compressed air.  You may have better luck.  An ultrasonic cleaner would probably help.
Excellent suggestion.  A WUR-size unit isn't very expensive and useful for many things.  If you rebuild the WUR be sure to polish the face surface with 2000 and 3000 wet paper and immediately dry with acetone or similar to prevent rust.  Mine also have 2 discs. 

As for the dust, I wonder if what starts as rust powder doesn't eventually kind of self-sinter into a hard mass when car sits too long.  Rust dissolves in acids but there are obvious problems with that.  I wonder if soaking in a weak acid like vinegar or citric acid would do the trick without corroding the WUR body?  Or ultrasonic cleaning using citric acid?  This must be an issue for the rebuilders.  I wonder how they handle it.
-Dave
Now:  1976 6.9 Euro, 2015 GL550
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

SteveDuNord

Quote from: raueda1 on 29 June 2023, 07:01 AM
Quote from: Feather535 on 28 June 2023, 10:09 PM
Quote from: SteveDuNord on 28 June 2023, 02:32 PMFrom what I can tell, there's nothing you can't calibrate on the car itself that you can on a test rig.

That's true, but in my experience calibration isn't the problem: cleaning is.  I wasn't able to get adequate flow through the inlet side of the WUR even with multiple soaks in parts cleaner and lots of compressed air.  You may have better luck.  An ultrasonic cleaner would probably help.
Excellent suggestion.  A WUR-size unit isn't very expensive and useful for many things.  If you rebuild the WUR be sure to polish the face surface with 2000 and 3000 wet paper and immediately dry with acetone or similar to prevent rust.  Mine also have 2 discs. 

As for the dust, I wonder if what starts as rust powder doesn't eventually kind of self-sinter into a hard mass when car sits too long.  Rust dissolves in acids but there are obvious problems with that.  I wonder if soaking in a weak acid like vinegar or citric acid would do the trick without corroding the WUR body?  Or ultrasonic cleaning using citric acid?  This must be an issue for the rebuilders.  I wonder how they handle it.

I might just order an ultrasonic cleaner. Surely will get some use out of it over the years.

When you say polish the face surface, do you mean the main joint where the gasket sits?

I might look into buying a drum to catch half a tank of fuel. Put a new strainer in as a minimum. Having messed around with the fuel pump, I'm more confident about removing the fuel line.

That being said, the fuel I collected in the fuel return flow test looked crystal clear to me.
'77 280se

raueda1

Quote from: SteveDuNord on 30 June 2023, 04:30 AM
Quote from: raueda1 on 29 June 2023, 07:01 AM
Quote from: Feather535 on 28 June 2023, 10:09 PM
Quote from: SteveDuNord on 28 June 2023, 02:32 PMFrom what I can tell, there's nothing you can't calibrate on the car itself that you can on a test rig.

That's true, but in my experience calibration isn't the problem: cleaning is.  I wasn't able to get adequate flow through the inlet side of the WUR even with multiple soaks in parts cleaner and lots of compressed air.  You may have better luck.  An ultrasonic cleaner would probably help.
Excellent suggestion.  A WUR-size unit isn't very expensive and useful for many things.  If you rebuild the WUR be sure to polish the face surface with 2000 and 3000 wet paper and immediately dry with acetone or similar to prevent rust.  Mine also have 2 discs. 

As for the dust, I wonder if what starts as rust powder doesn't eventually kind of self-sinter into a hard mass when car sits too long.  Rust dissolves in acids but there are obvious problems with that.  I wonder if soaking in a weak acid like vinegar or citric acid would do the trick without corroding the WUR body?  Or ultrasonic cleaning using citric acid?  This must be an issue for the rebuilders.  I wonder how they handle it.

I might just order an ultrasonic cleaner. Surely1. will get some use out of it over the years.

When you say 2.  polish the face surface, do you mean the main joint where the gasket sits?

I might look into buying a drum to catch half a tank of fuel. Put a new strainer in as a minimum. Having messed around with the fuel pump, I'm more confident about removing the fuel line.

That being said, the fuel I collected in the fuel return flow test 3. looked crystal clear to me.
1. I got this thing.  3 L version I think.  One of the best buys I ever made.  I use the "citrus" cleaner stuff from Home depot.  Works fantastic.

2. Obviously you need to knock the cylindrical valve body out of the WUR housing.  It's the surface underneath the thin diaphragms with the hole in the center and the o-ring.  Put paper on an ultra flat surface and wet-sand.  You'll see the surface change from grayish to mirror finish. Use a light touch, it doesn't take much.  Dry with acetone or similar. 

3. Initially I thought so too.  But after settling for a while that sediment was clearly visible. Maybe go
back and gently tap the fuel pump, return line, etc and see if you can knock something loose.  Sounds crazy, but.....
-Dave
Now:  1976 6.9 Euro, 2015 GL550
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0