WUR rebuilt kit?

yelcab1 · 05-20-2004, 05:12 PM

OK,

I found the problem for my low warm idle. The Warm Up Regulator no longer regulates. The control pressure starts at 55 psi cold, and ends up at 55 psi with engine hot.

My questions are:
1. Is there a rebuild kit?
2. Are there rebuild instructions somewhere?

Or, screw it and buy a new one at $349?

I do not want to make it cold-adjustable because if it does not regulate at all, then it is toast.

konish · 05-20-2004, 05:25 PM

Is the heating element cracked...i.e. are you getting any resitance at all across the connectors? My buddy's WUR wasn't working and we peeled back the pig tail leads and found that the ground wire had seperated from the plug. We would have never been able to see it without first testing for continuity in the wire from the plu side of each end. Check first before you spend $$. Also, there isn't a rebuild kit available....I searched LONG and hard before coming to that conclusion.
R/
Dustin

yelcab1 · 05-20-2004, 05:29 PM

Check the wires, got 12 V across the connector.
Opened up the WUR, measured across the element, got 20 something ohms of resistance. Cleaned it and put it back, with no change.

So, it is buy new or rebuild time.

radcon · radcon's Garage

Have you made it adjustable? If the plug has been knocked too far, the heating element won't be able to cause enough deflection of the metal arm to cause a pressure change. The wur is a pretty simple piece of equipment. If the heating element works and the regulator is cleaned out, there isn't anything that should prevent it from functioning if it has been properly adjusted.

oneblueyedog · oneblueyedog's Garage

Save yourself a real PIA if the wiring is OK. Order one from Pelican. The number has ben superceded which kind of freaked me out because I had spent close to a grand on the warm up circuit. I had bought a rebuilt unit that still made the car run horrible when cold. I replaced all of the hoses, even a vacuum valve (for sale if needed). I made the WUR ADJUSTABLE. Fun to do but, still ran like crud after. Last thing I did was flip the diaphram. No good. I checked the resistance in the heating element. ? So the adventure in futiity ended. I bought one from Pelican. Gave them some grief about the number. They kindly set me straight. I installed it. PROBLEM SOLVED. PERFECT!

If I have not apologised Pelican Parts, I hope you will accept it now. You're the greatest Porsche resource in the world, besides Porsche of course.

Lee 78SC

Brent 930 · 05-20-2004, 06:31 PM

If the heating element works and the regulator is cleaned out, there isn't anything that should prevent it from functioning if it has been properly adjusted.

Not true, more than likely the bi metallic strip is bad. Is there any evidence the large pem has been touched? If so someone was compensating for the bad bi metallic strip which is not the way to fix it. In any case there is no rebuild kits that we can get our hands on. That is a very tight market. You could send your WUR in on a core exchange and spend around $150 instead of a new one. I know the WUR really well and have another strip but not sure if it's the same one in your WUR.

Brent

cmonref · 05-21-2004, 03:38 AM

Here's a long shot. If the COLD pressure is 55 psi, then the bimetallic spring is not returning to its COLD position. Is it possible that you have 12v applied to the WUR at all times, even after you switch off? That would cause your symptoms.

konish · 05-21-2004, 04:44 AM

Radcon and Brian seemed to have nailed it pretty well....perhaps set too cold (i.e. your plug being set too deeply in the housing). When I set mine, I did not make the adjustbable plug, but simply used a long, thin bolt with two small nuts threaded on the end to act as a stop. Adjust the nuts to set depth a little at a time to prevent overshooting the desired pressure.

R/
Dustin

Brent 930 · 05-21-2004, 05:28 AM

If you knock the pem down the pressure will decrease, if the WUR was never monkeyed with the strip is bad, plain and simple. If 12v were there all the time his battery would be dead in no time. The WUR is very simple and if the thing is clean, resistor is good and you get 12v when the igintion is on then the only part that can go bad is the strip. The cold/warm control is adjustable from inside so it can be re caled from time to time since the strip will change a little over time.

konish · 05-21-2004, 05:47 AM

Brent,
You are correct, I wasn't making the mental leap of faith that 55 psi IS the warm control pressure. I would then have to ask if it would be possible to set the cold control pressure cold by setting the plug deeper to see if there is any change. True, if the WUR was working well before and if nobody messed with it, then it would suggest something else e.g. bi-metallic strip. However, how do the strips actually go bad? Just curious.

R/
Dustin

oneblueyedog · oneblueyedog's Garage

It was explained that there are 2 strips of metal that warp via a heating element that's activated electrically. After many years the metal gets less pliable (becomes tempered). Also the heating element can burn out (like a toaster) that is why mine tested open across the 2 terminals.

When I opened the rebuilt unit up the green insulation was fractured on the Bi strip.

The rebuild was bad. My lesson was costly. Buy cheap, buy twice.

Lee78SC

Brent 930 · 05-21-2004, 06:42 AM

Yes, they go bad.

Brent 930 · 05-21-2004, 06:58 AM

Whoops, not sure how they go bad but the one you have is. I can tell you this, when the WUR goes bad and you send in your core they just clean everything, replace the resistor/strip and connector assembly and test the pressures. Then seal it up and put it on the shelf for re sale.

yelcab1 · 05-21-2004, 09:29 AM

Thanks for all the responses. What I know is this:

1. It has always been bad since I bought it, before that I don't know.
2. 12V is there only with the key on, not there all the time.
3. Resistance across the filament is over 20 ohms, so it seems good.
4. Cold control pressure is 55 psi, warm control pressure is also 55 psi.
5. New one, with tax and shipping from our host is >$400

I can clean it and recalibrate it if some one (Brent930) can give me a procedure to do that.

Brent, you said that the control pressure can be "calibrated" from the inside, can you tell me how?

I will tinker with it some more before spending $400 (for a housing, a metalic strip, a plunger, a spring, a resistor, a connector, and some wires)

Thanks ahead for the help.

Brent 930 · 05-21-2004, 10:12 AM

You can re cal it if the WUR is already good. In your case it's not and you need to get it fixed. There is a hex screw inside the bottom plate that can be adjusted to change the cold/warm pressure. I have an extra strip that should work in your WUR. You can send it to me so I can examine it and see if it will work. Even though it's not the right WUR for my car I could probably test it too. Or you can go through Special T Auto and look up your part # and see how much a rebuilt one will cost. Shouldn't be more than $180 with the core return. Let me know,

Brent

Brent 930 · 05-21-2004, 10:16 AM

Is the part # of your WUR 0-438-140-072?

Brent