New WUR - Couple of Questions

Tidybuoy · 08:45 AM

I got a new WUR and installed it today. Havent yet checked pressures or exhaust mixture but I will be doing that next weekend.

I purchased the new WUR on eBay about a year ago. It's brand new and correct (I think) for my '74. The old WUR was not for a '74 bt I'm not sure if that mattered.

New WUR 0 438 140 009
Old WUR 0 438 140 033

The car has been running awful lately with hunting idle, hard to start, smelled rich. Since I was replacing all the fuel injector lines today, I decided to switch to the new WUR just to see what happens.

Car instantly ran better with instant startup and no hunting idle. Runs very smooth at idle. Took it out for a drive and it feels like I added 10 hp as the engine runs very smooth with great pickup. However, at steady cruising, the engine jerks a little bit. I also noticed a couple small backfires in the muffler.

My Questions:
1) Old WUR (which was not correct for '74) had a very small vacuum port coming out the bottom/side. This was connected direct to the throttle body. New WUR does not have this vacuum port. I plugged the hose but what is correct for my '74? Prior owner stated the car has a '76 FI setup so I'm assuming that the throttle body has additional vacuum ports? Is this ok to just plug the line or should it be connected so something else.

2) Is it normal for a new WUR to need adjusting (i.e., the bolt that gets tapped in futher to increase pressure or backed out to reduce?) Or, is the only typical adjustment with the richness/mixture screw? I noticed that the old WUR, this bolt was tapped in about 1/4 inch where as the new WUR the bolt was almost flush witht he top of the case. I Will check my fuel pressures this weekend before doing anything.

3) Electrical plut to WUR looks bad. Both wires coming out of the plug are cracked and showing bare wires. None of these wires are grounding out and I will look for a new plug but how does this affect the WUR - is this only during warmup?

Anyway, thanks in advance for any advice.......Vern

T77911S · 01-22-2013, 07:21 AM

it does not sound like you got a new one.

has it been modded so it is adjustable?

no, NEW ones dont need to be adjsuted.

also, you should put on the WUR for the CIS system installed, not the year of the car. so you need a 76 WUR, like the one you had on, the 033.
the 033 has a vacuum enrichment port, the port that you no longer have. this could make the car run lean at WOT.

the power connections need to be connected. you need to post of a pic of what you have because i am not sure of you explanation.

i did not see a 006 WUR. i saw a 009 for 74.

i dont know the specs of the one you bought but if it comes down to it, you may be able to make one out of the 2.
if the vacuum diaphragm os good on the 033, i would swap out the bi-metal spring and heating element. that is just me, not saying you should do it because i dont know all the specifics of your situation since i am not there.

again, some pics of the WUR may be helpful.

Tidybuoy · 01-22-2013, 08:51 AM

It's definately new - I may have described that plug/pin/bolt in the top that can be tapped to adjust the pressure.

It's an 009 (I miss typed).

Got it on the "use the same one for CIS system". I plan on cleaning and rebuilding my 033 so that it is in like new condition.

The power is connected. It's just that the wires to the plug are a little sloppy and I need to replace the plug with a new one. It is still working though.

I wish I had taken some photos before I installed it. I will get some later this week when I have time.

Thanks.....Vern

T77911S · 01-22-2013, 09:45 AM

its still the wrong WUR.

i would put something like an LM2 on there where you can record the mixture and do a few runs up to redline.

i have removed the vacuum on my WUR on my 77 and it runs like crap. steady driving was fine, just could not accelerate. throttle response was crap. i did have some other issues at the time though.

Tidybuoy · 01-22-2013, 10:48 AM

Thanks for all the info.

I will probably put the old 033 back on this weekend but I'm going to give it a good cleaning first. It looked like the screen was dirty and possiblly a bit clogged.

I also have a rebuild kit for it so I will get that done too - it's just gaskets and an o-ring, and the vacuum diaphram. I'm pretty sure the bi-metal strip was working fine as the engine would reduce idle after about a minute during warmup.

Although I've gone about this in the wrong order, I will test my fuel pressures this weekend. I was waiting until I got all the CIS fuel lines replaced before doing anything because I didn't want to take the chance of damaging them (their old). But I changed all the lines this weekend and now I'm good to go. I will probably need to post the pressures on this forum to help interpret.

Vern