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Discussion Starter #1
Hi all, After replacing just about every piece of rubber and plastic I can think of, I've decided to turn my attention to the fuel system. Anticipating the inside of my WUR to look as bad as the inside of my intake (Black-Carbon-Goo) I endeavored to open it up and give it a good clean. It looked nearly perfect! Until I noticed all the slits in the Diaphragm gasket that separated the two halves.

The EPC I use is down, so I can't check... However, I don't believe the WUR is considered to be "serviceable?" My question to all you is: Can this Diaphragm Gasket available and where?

Thanks, in advance, for your responses.
 

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I happened across a place online. "Special T Auto" Located in Texas, they offer remanufactured units. However, it appears they may not still be in business? Has Anyone purchased from these guys recently? All Warmup Regulators | SpecialTauto.com

I welcome other suggestions or sources.
 

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Communications with the Texas company offering the rebuilt WUR was proving difficult, so I decided to go with the rebuild-kit out of Australia. They offer a pretty good set of instructions so I'm hopeful everything will go ok? As this doesn't appear to be a hot topic I'll continue to post my progress for posterity sake.
 

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Please do. The WUR is more important than people think. It will be nice to have a w126 specific documentation. Most everything out there is for the Porsche boys.
 

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CIS Flowtech in Hope, Alabama has a sterling reputation for both rebuilt fuel distributors (where I got mine and working perfectly) and WURs. This latter, however, is a bit pricey when compared to kits. On the other hand, labor is included and done right, and I know my limits.
 

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Ok I'm back. Kit arrived late yesterday afternoon. While I was waiting, I completely tore the unit apart and cleaned the heck out of it. Reassembly only took about an hour. The instructions were pretty good, however when it comes to calibration I'm a bit confused. The instructions seem a bit incongruous and are leaving me with basic questions. For example, can anyone tell me if the main manifold vacuum port ( big one on the side ) is designed to hold vacuum or is designed to respond to vacuum. BTW My WUR is a Euro ending in 101.
 

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Ok I'm back. Kit arrived late yesterday afternoon. While I was waiting, I completely tore the unit apart and cleaned the heck out of it. Reassembly only took about an hour. The instructions were pretty good, however when it comes to calibration I'm a bit confused. The instructions seem a bit incongruous and are leaving me with basic questions. For example, can anyone tell me if the main manifold vacuum port ( big one on the side ) is designed to hold vacuum or is designed to respond to vacuum. BTW My WUR is a Euro ending in 101.
Hi there,

At the dawn of time, I used to work with these systems on a daily basis...

The regulator is designed to read/respond to manifold pressure during operation. [So no check valve.]

MBL
 

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Discussion Starter #11
Update: Finally found someone to lend me a CIS fuel pressure tester. Having said that I'm still waiting... In the mean time I've done two things. 1. Begun to collect parts needed to make my own fuel pressure tester. 2. Ordered, received and rebuild my K Jet CIS. It Starts, but idles very bad and after about 1 minute stalls. O-rings in the kit that appeared to be designed to replace those on the Pressure Regulator looked too small? I installed them anyway and now I'm thinking they may be my culprit? Think I'll need kit 3437010021 to get the correct O-rings? I'm going to start another post soon on trouble shooting a CIS rebuild kit. It's becoming very clear to me that everything seems to be revolving knowing and adjusting my fuel control pressure.
 

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Discussion Starter #13
Finally received a nice quality fuel pressure tester from BAUM. It was a little more $ but quality seems really good. Plan is to start testing my fuel pressures starting with pressure from the pump. However, I'm having trouble navigating the new site format. Did we lose all the stickies and access to that online version of the shop manual? I'm looking for testing procedures relating to fuel deliver starting at pump, accumulator etc. Also test procedures for CIS pressure regulator. I have a good writeup for the WUR but need to go much further back now.
 

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Just found this thread and am resending to get it back in the "system." Looking forward to continuing to hear Festool's progress although am still leaning towards replacing Warmup Regulator (WUR) with rebuild from Larry at CIS Flotech but also checking out Delorian Auto Parts recommended on another thread.

Edit: to clarify that Deloran Auto Parts is not/not related to Delorean Motor and that its website is down for maintenance. It used to be Special T and that web site is still up and provides info and prices on Fuel Distributors and WURs.
 

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i sent my FD to larry to have rebuild...decided to leave the WUR as its fine
 

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Did we lose all the stickies and access to that online version of the shop manual?
I do hope all that functionality will return in time...


I'm looking for testing procedures relating to fuel deliver starting at pump, accumulator etc. Also test procedures for CIS pressure regulator. I have a good writeup for the WUR but need to go much further back now.
Here are some Fuel PDFs from the MBCDs for you.
Hope there is something of value there.

MBL
 

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Discussion Starter #17
Just a quick glance indicates they hold a lot of useful information. One big question remains, however. I can't seem to find any information regarding the Vacuum requirements for the WUR. ie with a double diaphragm unit such as mine ending in 101. Are the upper and lower chambers supposed to hold vacuum for long periods of time? Mine bleed to 0 in 15-16 seconds. Having said that my pressure numbers appear to within spec. 2.0 Bar cold, and 3.4Bar warm. based on ambient temperature chart. Anyway, I'm getting frustrated with not knowing if the WUR should hold vacuum at all ports or not? Or, if some bypass is ok?
 
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