Ahhh, Went from Bad to Worse - Fuel Distributor

[Tidybuoy]

I have a '74 that came to me with a '79 fuel distributor and a '76 #033 WUR. The car ran well for many years.

I posted in another thread about my injectors squirting lightly when the engine is off but fuel pump running. I concluded that it might be the fuel distributor since I had removed, let sit for a few months, and the piston froze up (freed up after soaking).

I bought a used Fuel distributor on the classified - same '79 model. It came with the WUR and supposedly was from a running car.

I swapped the fuel distributor but could not get the car to start. It would start and run for 30 seconds and die. I tried tweaking the mixture, thinking that this could be the issue and would measure the exhaust and adjust after I get running. BUT, could never get to run.

I put all injectors into jars to see the flow rate and all were filling the same but one jar came out brown with lots of sediment.

I swapped back to my original FD and adjusted the mixture with an exhaust gas analyzer but the car is running rough and bucking at cruise or low rpm.

Does it seem likely that the new FD clogged my "brand new" injectors? I should have know better to flush out the new FD since it was fairly dirty on the outside and the air sensor (which I did not use) was filthy.

Lastly, the WUR that came with the FD is an 069 which is for a 928. The seller "claimed" it was on his running '79 - does this seem likely?

RE: Fuel Pressures, Last time I checked (about a year ago), they were in spec. I will check again this weekend.

RE: Vacuum Leaks, I have replaced about everything rubber on the car. The only thing left that I have not replaced is the air box. Is there a good way to test this for leaks?

[pete3799]

I believe my 79 RoW has an 069 on it.

[Charles Freeborn]

There were changes to the K-tronic over the years, and the various system pressures varied along with the changes. The WUR also went to a vacuum enrichment somewhere in that span, so you may have parts that use different specs.
-C

[javadog]

There are quite a few 911s running around with jury-rigged CIS systems. They generally have one or more issues. I think it is these cars that give CIS a bad name. A complete and properly adjusted CIS car runs pretty nice.

In my opinion, and I am we'll into my fourth decade of driving CIS cars (none of which had running problems), you should stop where you are, find and install the right components (making sure you are not buying someone else's non- functioning junk) and tune and adjust it from square one.

JR

[T77911S]

you can always pull the injectors and do another flow test.
at the least i would pull the one injector and turn it upside down and spray some carb cleaner in it.
i would have just pulled your FD and cleaned the piston and the barrel it slides in.
you need the 033 WUR or one like it with the vacuum enrichment. i dont know if the 069 has it.
other than that any WUR can be set to work with any FD.

[boyt911sc]

Originally Posted by javadog

There are quite a few 911s running around with jury-rigged CIS systems. They generally have one or more issues. I think it is these cars that give CIS a bad name. A complete and properly adjusted CIS car runs pretty nice.

In my opinion, and I am we'll into my fourth decade of driving CIS cars (none of which had running problems), you should stop where you are, find and install the right components (making sure you are not buying someone else's non- functioning junk) and tune and adjust it from square one.

JR

+1. CIS troubleshooting is easy and fun if you stop doing guess-work. All these CIS components could be bench tested and confirmed good or bad by DIY'ers using basic tools and set-ups.

Tony

[Grezdlitn]

- - CIS fuel distributer cleanout w/pics (CIS fuel distributer cleanout w/pics)

This is an old thread I posted several years ago. There may be some help in it that will help you figure out your rough running engine. My old SC was behaving like you have described.
Good luck,
Mark

[Newfie911s]

I had to clean the little filter screen on the input side of the WUR as well.

Over time that little thing was pretty dirty.

[Tidybuoy]

Thank you all for the good advice.

Thanks especially to mark for posting a great thread on the fuel distributor. I think that I may pull apart the dirty one that I just bought and follow the steps on Mark's thread.

I did find some rebuild kits on eBay which consist of all the O-rings (using Viton) and the stainless membrain. After seeing your pics and the gunk that came out of this FD I bought, I suspect that a thorough cleaning might be in order.

Vern

[Charles Freeborn]

Contact Us - CIS Flowtech
DeLorean parts, Delorean fuel distributor, CIS fuel injection Parts, Delorean parts, Porsche Mercedes

[javadog]

Here's a complete '74 CIS system:

FS: 74 CIS + working WUR

That one took 5 seconds to find. There are probably others. Why not buy something like this, clean it up and put it all on your car? Then buy a '74 spec book (I have a new one of those laying around, I think) and spend your time getting the car sorted out with all of the right components?

JR

[T77911S]

look at post #2. DO NOT pull that cylinder out of the top half of the FD.
the slits in the cylinder have to line up with the slits in the top half of the FD.
the only was i can figure to do this is to make a jig that lines it up after it is back together.

[RarlyL8]

... or you can stop wasting money and send the parts in for a rebuild. Due to the dirty fuel head you are in worse shape now than when you started. I've been on Pelican from the begining and we stand behind our work.

[Tidybuoy]

Originally Posted by javadog

Here's a complete '74 CIS system: Why not buy something like this, clean it up and put it all on your car? JR

My car ran great when I bought it several years ago. I only bought a FD because my injectors were pulsing and the air flow sensor appeared adjusted correctly. I had removed the FD when I removed the CIS for oil leak repairs. In the process, I replaced all vacuum related items but the piston in the FD froze up.

My goal is to fix the system that I have that I know ran well. I goofed up when I bought a dirty item and tried to use. I really don't want to buy a complete CIS system that may or may not have the same issues - I will just fix what I have.

Originally Posted by RarlyL8

... or you can stop wasting money and send the parts in for a rebuild. Due to the dirty fuel head you are in worse shape now than when you started. I've been on Pelican from the begining and we stand behind our work.

I've looked at your site and I just may do this. I just might have to wait until after Christmas. Until then, I put the orig FD back on and the car seems to be running ok - just not perfect.