924Board.org

[JoeShmo]

so I took the filter out, and sure, the gas was a little brown on the output side, but the INPUT side was real nasty. I poured from the inlet and outlet into a jar, and this is what I got:



So its as if the gas is completely saturated with that brown stuff. its already settled about 1/8+ inch of it on the bottom of the jar, from just that little amount of gas.
So does the tank need to be replaced? or can I run it through to a gas can, try to filter and put it back? or is the interior of the tank actually deteriorating? I havnt found pricing for new tanks yet, but I know its not an easy job. How about a plastic tank I can just put in the "trunk"?

[dpw928]

Could be lacquer from old gas or rust. If it smells like old paint, it just needs cleaned. If it is rust, you might try fixing it with a liner kit like JC Whitney sells.

Dennis
_________________
81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

[JoeShmo]

I decided to resserect this old thread, as to not hijack others...
fuel looks clear flowing now... I'm wondering about the accumulators (yes, 2, as I have the 77 M&R (as in not a 77.5)). Each is 20cc. The screws at the bottom require a thin slotted screwdriver. I already broke my (cheap) thin screwdriver trying to get one loosened to see if the diaphram was toast.

Is there anything in this new, modern day & age that I can use to replace those two 20cc accumulators? Altho, I'll try to get under there again tomorrow and get the screws loose. But seeing as my pressure immedately drops to 0 when the fuel pump turns off, they are suspect (already cleaned out the spring-loaded relief valve on the fuel dist, and checked it).

Also, my JC Whitney fuel pressure tester does not have an adaptor to connect to the fuel filter "out" side, nor the line coming to it, so hard to check pump pressure. Especially since the banjo bolt going into the fuel dist has two leads coming off from it, so cant just isolate the incoming side. But may be able to block that other lead when I find where it goes.

(By the way.. anyone wanting me to check/clean the in-tank pump, this car doesnt have one. Those were on "later" models).

- - - 1977 N/A 924, Martini & Rossi

[nivekrs]

If your accumulator was bad it probably wouldn't fire right up though since it is responsible for keeping residual pressure in the system for start up. At least that is the rationalization I used to eliminate it when diagnosing my similar problem which we talked about yesterday. Btw, I took the fuel distributor off today and found it had no O ring... Hmm, think I found the problem. (crossing fingers) currently trying to locate one. Also took off warm up valve (control pressure regulator) the inlet has a screen on it and it had a lot of crud stopping it up. so i cleaned it out. didn't fix problem, but glad I cleaned it out anyway. still need to check it with an ohm meter just to make sue it is still working.

[JoeShmo]

where did you find the "warm up valve (control pressure regulator)" in which you speak of? Is that also known as WUR (Warm up regulator)? I THINK that is tward the firewall, kind of buried, and looking impossible to get to on mine. I might be able to get the banjo bolts out, but as for removing the unit itself to clean, don't know...

One thing leading me to check accumulators is the royal pain it is keeping the car running when its warm. I have to play with turning on the cold start injector, and start the car a few times, and eventually it'll stay running. However, letting the car sit for no less than 3 hours(!!!) on a mild day, it would start. 2 hours no. This was of course back when the car was running. And I've read about bad hot start problems even with workaround because caused by bad accumulator(s).

[nivekrs]

Right. That's true. When the baffles warm up they tend to be less effective in an accumulator that is on it's way out. At least that's what a mechanic told me. Says it can be a tell tail sign accumulator needs to be replaced. Yes, the WUR is on the back of the intake even with the bottom of the coil. Had to take coil off, unplug cold start valve, undo a vacuum line and pul/push many wires aside. Took an hour to get the bottom mounting bolt back in. Had to turn a hex socket with my fingers until it was snug and then put the wrench on and give it one get pull to tighten because there wasn't room for the wrench until it was all the way in. Plug is still easy to get to so i can check resistance. Haynes says 20 Ohms. Need to buy a multimeter. Don't really know how to read one. all the ones I looked at had 200- 20k adjustments on the ohms not sure how to check something that is supposed to have only 20.

[JoeShmo]

ok, so I cleaned up the tank as best I could.. Installed a fuel filter between tank and brand new fuel pump. I can now easily get 5 bars of pressure, but at that pressure, the input of the normal (under hood) fuel filter leaks. So I tightened that, and now it leaks even more. Wondering if I broke something. Got a bit too dark out, so could not see exactly where its leaking from, high pressure clamp, or threads onto the fuel filter.

Is there a way to ensure a good seal on the line that goes to the filter? Theres no gasket there, just metal ball shaped thing into a tapered fitting on the filter.

I suppose if someone has a parts car kicking around, I can get that little 1 foot hose from them, if thats what the problem is. (part number 477 209 075).

--- 1977 NA 924 M&R

[nivekrs]

Well,I got mine running on Wednesday.I started and ran fine.(Took fuel distributor off,cleaned and replaced O ring) But, it seemed like it would start out really quick but then as the RPMs rose it just didn't have much at all. I decided to replace the fuel filter and noticed that the fuel line goes into the bottom ("in") of the fuel filter an then connects at the fire wall was severely kinked. (A steel line with a 45 and then a 90 straight up to the fuel filter, and 2 male connections and crimped nipples on the ends) It seems the previous owner must have continuously twisted it every time he put on or took off the fuel filter. (Is that the fuel line you are talking about). I brought the piece of line to my import guy and he explained that he doesn't make those. He special orders all that kind of stuff. Apparently that is a special crimp only VW/Audi and Porsche use. So I got on the parts catalog but nothing really looked 100% right and this is a very specific piece. So on a whim I checked Ebay and found a brand new fuel line for a 911 part 964-356-065-01,but it is exactly what I need. same bends and everything. Btw, did you check to see if the copper washer is installed between the filter and the brass adapter which connects to the fuel line. sounds like that. Unless you have my problem and the line is twisted and possibly cracked.

[!tom]

[nivekrs]

Yeah, I figured it out. My WUR was fine. Just waiting on the fuel line now.

[JoeShmo]

Ok, used the old fuel filter I had kicking around, and was able to tighten it. And yes, the copper washer things are there.

Car starts, and idles fine now. Although at higher RPMs its skipping (or sounds like it).. I pulled each plug wire one at a time, and restarted. sounded exactly the same each time..?!

Another bonus is that I no longer have the hot start issue. Even when warm, car starts right up. I think before, because of lower fuel pressure, and not holding pressure, I constantly had to quickly restart using the cold start injector, and after a while, fuel finally built up (took about 7 or so tries, playing with the injector switch a previous owner put in to get it to stay running). Now, when hot, switch isnt needed at all.

So, I mention all that because of the current misfire sounding problem. I remember reading another thread where someone mentioned playing with the mixture control since a car was running too rich. I'm wondering if the PO richened up the mixture, because fuel pressure wasnt where it should be. But I really dont want to play with that unless I'm sure everything else is ok.

I checked with timing light, and the vacuum advance does seem to be working.

So I'm guessing maybe a compression test may be in order? The thing is, the car was running fine before, just had a hard time starting, then wouldnt start at all. BTW.. plugs, cap, rotor, and wires are all new. All Bosche parts except for champion plugs.

[nivekrs]

Maybe oxygen sensor. My Volkswagen was "fluttering" at high rpms and that's what it was. They screw up the air/fuel mixture when they go. Pretty easy fix, cheap part.