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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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 Posted: Fri Oct 10, 2014 10:00 am Post subject: |
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Uggh! I took the advice of this thread and started at the gas tank. First thing I did was remove the sender. This is what it looked like.
First of all that's the weirdest sender I have ever seen. Any chance it still works? The tank had 7 or so gallons of fuel in it and it was absolutely putrid! It's brown in color and it doesn't even smell like gas. What is the best way to dispose of this stuff?
My car appears to have both an in tank pump and external pump. My Haynes manual only talks about the external pump. How do I remove the internal pump? Do I have to drop the tank? Got any good methods for cleaning the tank or should I take it somewhere to be boiled out?
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jason c
Joined: 13 Jan 2014
Posts: 1018
Location: Nwi
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| Posted: Fri Oct 10, 2014 12:02 pm Post subject: |
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| oharris wrote: | Uggh! I took the advice of this thread and started at the gas tank. First thing I did was remove the sender. This is what it looked like.
First of all that's the weirdest sender I have ever seen. Any chance it still works? The tank had 7 or so gallons of fuel in it and it was absolutely putrid! It's brown in color and it doesn't even smell like gas. What is the best way to dispose of this stuff?
My car appears to have both an in tank pump and external pump. My Haynes manual only talks about the external pump. How do I remove the internal pump? Do I have to drop the tank? Got any good methods for cleaning the tank or should I take it somewhere to be boiled out? |
The fuel lines under the hood are just plastic lines with rubber covers. The cover is just for heat and abrasion resistance. There is no braiding.
You may be able to clean the sender if you can still hear the float sliding when you turn it over.
You might be able to dispose of that gas at an oil change place.
You can try to clean the tank yourself but if you arent comfortable dealing with chemicals, have it boiled.
The in tank pump unscrews from the bottom of the tank where the fuel line and electrical connectors come out. No need to remove the tank for that. |
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Fri Oct 10, 2014 2:19 pm Post subject: |
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Thanks! I got the pump out. There was so much gunk in the bottom of the tank the pump twisted free from the mounting plug and broke the wires and the hose. Not sure I can save it.
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Sun Oct 12, 2014 4:11 am Post subject: |
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Neither fuel pump works. I'm going to replace them with a single Walbro. I moved on to replacing the timing belt. Tried to turn the engine over but it is stuck. Going to pour some marvel mystery oil into the cylinders. I also opened the metering box (is that the right name?) Cleaned it with carburetor cleaner; now it moves freely, but it doesn't return to closed by itself. It seems to be balanced with the counterweight. Is this how it's supposed to be? Does fuel pressure provide tension to close the metering plate?
I'm finding it very hard to believe this thing ran 3 years ago. 10+ years ago seems more likely.
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JLWturbo
Joined: 18 Oct 2014
Posts: 4
Location: Maine
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| Posted: Sat Oct 18, 2014 2:15 pm Post subject: |
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At that price I wouldn't worry about a thing, and it sounds like you're making good progress! My baby is going to need the same work done as it had sat for a long while. Thanks for the detailed pictures, I'll be joining the fray soon. We'll resurrect them I'm sure.
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1982 Porsche 924 Turbo
2005 Saab 9-2X Aero
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Fasteddie313
Joined: 29 Sep 2013
Posts: 2596
Location: MI
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| Posted: Mon Oct 20, 2014 7:02 pm Post subject: |
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| oharris wrote: | | Fasteddie313 wrote: | the injector looking thing = frequency valve
pretty much what it does is open and close all the time at varying frequencies adjusted by the lambda circuit, sending some fuel back to the tank, to fine tune the air fuel ratio against what the 02 sensor tells the computer.. it changes the fuel differential pressure under the diaphragm in the fuel distributor to speed or slow the flow of fuel from the metering ports in the piston due to pressure differential, more difference = more flow |
Thanks! Wow, I've got a lot to learn about CIS.
| Fasteddie313 wrote: | if its a bare braded wire its a ground
that sensor on the charge tube "overboost sensor" cuts fuel in event of overpressure due to a malfunctioning waste gate so it wont just produce unlimited boost..... the wire that goes to this sensor needs to be grounded in order for the fuel pump relay to come on, an overpressure situation ungrounds the sensor and stops the fuel pumps...
in short just ground that wire to get it to run.. |
Got the function, I'm just trying to determine if it's the right wire.
| Fasteddie313 wrote: | I wouldn't advise disassembling the fuel distributor yourself, atleast not without a lot of research, a very clean place to work, and a micrometer style depth gauge to put it back together correctly... yeah that piece is $$$ and very precision
TECHTRON injection cleaner!! |
Yeah, I think I'm going to try dousing it in cleaner first. It definitely needs cleaned. I took top of the air cleaner off to expose the metering valve (I guess this is the mechanical equivalent of a MAF in an EFI system). I pushed it down a little and it didn't come back up. Very sticky. |
yeah, I think the k-jectronic is an amazingly nifty system...
the "control" fuel pressure is responsible for the fuel pressure to the top of the piston, witch pushes down on the metering arm, witch is what that metering plate is attatched to..
long story short, if you don't have fuel pressure in the system theres nothing to lift that plate back up after you push it down..
and it shouldn't just freely float up and down, it should have very smooth resistance to push it down, mine feels like a shock absorber
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Thu Oct 23, 2014 6:53 am Post subject: |
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| Fasteddie313 wrote: |
yeah, I think the k-jectronic is an amazingly nifty system...
the "control" fuel pressure is responsible for the fuel pressure to the top of the piston, witch pushes down on the metering arm, witch is what that metering plate is attatched to..
long story short, if you don't have fuel pressure in the system theres nothing to lift that plate back up after you push it down..
and it shouldn't just freely float up and down, it should have very smooth resistance to push it down, mine feels like a shock absorber |
Now that I've cleaned it up, it moves pretty freely, but it has no fuel in it so I suspect that's the reason. I just got the gas tank back from being boiled so as soon as I get that installed along with my new fuel pump, I'll put some fuel to it and see where I'm at.
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Sun Dec 07, 2014 2:09 pm Post subject: |
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After a long hiatus (spent working on my son's Mustang) I am finally back to working on my 931. I replaced the dual fuel pumps with a single Walbro, replaced all the rubber fuel lines. I soaked the fuel accumulator in carb cleaner for a couple of days, then put it all back together. To test it, I hokked up the fuel distributor, pulled the fuel injectors and put them in empty water bottles. After jumping the fuel relay, the 3 & 4 injectors were spraying, but the other two were not. I gave them a tap and they started working just fine. After that, all four seem to be spraying evenly. The problem though is that they seem to be spraying way too much, a few ounces in each bottle after just a few minutes, and it doesn't seem to matter where the metering plate is. Also it still doesn't return to the closed position even with fuel pressure applied. So it seems I need to rebuild the fuel distributor. Is there any alternative to a full rebuild? I was hoping I could just replace the o rings on the control rod.
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jason c
Joined: 13 Jan 2014
Posts: 1018
Location: Nwi
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| Posted: Sun Dec 07, 2014 3:06 pm Post subject: |
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| The control pressure acts as a return spring for the plunger. If you don't have proper control pressure (or any at all), you should be looking at the wur (warm up regulator, aka; control pressure regulator). The wur varies pressure on the plunger to govern the mixture based on temp (cold start system). |
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Sun Feb 15, 2015 2:27 pm Post subject: |
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I finally got back to work on this. I jumped in with both feet and took the fuel distributor apart. I got the center rod free and soaked the pieces for a couple more weeks. I ordered a rebuild kit with new o rings and a new diaphragm. I put it all back together and tried it again. It seemed to work! With the meter plate closed, nothing came out and the further you pressed down on it the more fuel came out. It didn't leak either so I put every thing back together. I also fixed all the wiring and changed the oil. I tried to start it, but no such luck. It has spark, but it seemed kind of weak when I tested it. I got a big backfire through the air meter so I may not have the timing correct. I'll verify that soon, but is there anything else that might cause it to not start?
Also, the oil filter was the most difficult to change that I have ever seen. It hit the side of the block as soon as I backed it out a little bit and the new one did the same thing. Is there a better size or a remote filter kit that works?
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jason c
Joined: 13 Jan 2014
Posts: 1018
Location: Nwi
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| Posted: Sun Feb 15, 2015 3:11 pm Post subject: |
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There's a lot that could keep it from starting. Weak spark, timing, vacuum leaks, improper CIS adjustment.....
Is the cold start system functioning? Have you checked your pressures? Since you've went through the fuel distributor, you're going to have to start at square one on the CIS and should anyway. |
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oharris
Joined: 06 Oct 2014
Posts: 37
Location: Peyton, CO
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| Posted: Sun Feb 15, 2015 4:36 pm Post subject: |
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| jason c wrote: | There's a lot that could keep it from starting. Weak spark, timing, vacuum leaks, improper CIS adjustment.....
Is the cold start system functioning? Have you checked your pressures? Since you've went through the fuel distributor, you're going to have to start at square one on the CIS and should anyway. |
I have not checked my pressures. I tried not to mess with anything while it was apart; I was hoping to avoid getting it out of adjustment. Can a vacuum leak prevent it from starting? There isn't really a whole lot of vacuum during cranking is there?
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Rasta Monsta
Joined: 12 Jul 2006
Posts: 11727
Location: PacNW
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| Posted: Sun Feb 15, 2015 4:48 pm Post subject: |
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It's not gonna fire until the WUR is also cleaned out/rebuilt/replaced.
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jason c
Joined: 13 Jan 2014
Posts: 1018
Location: Nwi
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| Posted: Sun Feb 15, 2015 5:29 pm Post subject: |
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| oharris wrote: | | I was hoping to avoid getting it out of adjustment. |
That ship has sailed. The sensor plate adjustment is sensititve, the thickness of the gasket you replaced will change the adjustment.
| oharris wrote: | | Can a vacuum leak prevent it from starting? |
Yes, any unmetered air will create a lean condition. A cold engine needs more fuel than a warm engine so being lean on top of a cold start system (which includes the wur) that is not functioning properly is bad.
The wur (warm up regulator) Richens/leans the fuel mixture based on temp. The CSV (cold start valve) adds a shot of fuel upon cold startup. If these aren't working, starting will be difficult. Checking pressures will tell you if the wur is functioning and will be necessary to make adjustments.
If there's anything else in the fuel system that you haven't cleaned or replaced now is the time to do it. |
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