Sad tale of dispare
All the following is covered in another post with about the third time through the CIS system found here:
https://forums.turbobricks.com/showthread.php?t=348861
But I will post a few of the highlights in this thread which is my diary of my life with a Bertone.
Where I left off in about post 648 in this thread was that I had lost fuel pressure.
Hooked up the TurboBricks brand fuel pressure test equipment and only get 20 psi at the Control Pressure Regulator with the valve open and that is close . . . but . . . with the valve closed I get the same reading. Should be 70 psi. Both pumps are running in 'start' and jumpered at the fuel pressure relay.
Both lift and pressure pump have been replaced since I tried to pump 20 years of gas tank rust through them some years ago. Remember, it ran 40 miles to/from the paint shop since anything was done to affect the fuel system.
Other than spraying gas everywhere the fuel distributor to CPR connection is the only place I know to open the system to test pressure. A hose blew off the V8 conversion project at 90 psi and dumped a gallon of gas in about 5 seconds so I am aware of what that much pressure will do. I ran.
Since I replaced the original completely failed pressure pump with a cheap universal pump that probably cost $20 on ebay that didn't even physically fit I upgraded to a $30 pump that did fit the mounting hardware. Bench tested it before installation. It is marked + and - so got that correct and it is pumping some gas.
CPR reading with valve closed remains 20 psi. My logic process says that even if severely restricted the pressure should have gone up over a minute or two.
The only thing that I can think of that would maintain a steady inappropriate pressure is that the fuel distributor pressure regulator is stuck open to some extent and dumping all the pressure back into the tank.
I put a new pressure pump in and the guage displays the same pressure the previous pump did. Car ran before and without changes to fuel system except that I put another 5 gallons of fresh gas in the tank.
Set up to drain the tank with the tank pump. Nothing comes out. I can hear the pump running but nary a drop of gas.
Pulled the lift pump and found the hose between the pump and exit tube had dissolved. Yeah, it looked like a butyl hose expected to work submerged in gas. Even the rubber top cover of the pump was distorted.
It didn't appear to have been able to pump much gas before completely failing and I can only hope that the fuel filter caught most of anything that moved.
Got a new Delphi, made in America, pump in hand. From the looks of the age of the box this guy may have been manufactured when Delphi was part of General Motors.
But . . . it came with with a 2" piece of non-reinforced hose that looks far more like extruded butyl than the 30R-10 spec submerged fuel hose. It also came with squeeze clamps for the extra large diameter hose.
With this experience it would make me feel better to have the SAE code printed on the hose. The local NAPA store did not stock the 30R-10 but can get it. Ebay sellers included several marine supply stores which I have a couple around Lake Blue Ridge.
OK, the $4 an inch hose arrived. It did not have the SAE 30R-10 printed on it but it did have 'submersible fuel hose' there.
Siphoned the gas out of the tank and only got less than 6 gallons, 5 of which I had put in only a couple weeks ago. Interior of the tank looks OK. at least no rust areas. I will get some brand new gas tomorrow, get the pump in and expect nirvana. Often disappointed.
One last question: Is the pictured wiring correct? The replacement pump terminals are not marked and this is sorta how I remember it. The yellow ground wire was probably brown 30 years ago.
Cranked right up! Responds to throttle.
Been here before . . . several times.
The control pressure is reading the expected fuel distributor regulator pressure of about 70 psi. Should be low 20's with a cold engine. Appears that the CPR is blocked or at least is not regulating.
Off it comes . . . again . . . probably for about the 4th time.
But the rest of the fuel system seems to be working as intended. Both pumps now known new and a new filter.
Are we having fun yet?
<hr style="color:#999999; background-color:#999999" size="1"> I have had the CPR apart since the last post and did not find anything of significance but upon reassembly I am still getting system pressure.
One strange thing is a little quarter inch piece of what I thought was an O ring was in the CPR input screen. It had a hole and therefore tubing so it had to have been inside something else. Didn't seem like fuel distributor O rings. I have been there also some time ago.
The one thing I have not done is dig out the filter screens on the input. Air blows through just fine so one might think that fuel would pass the other way. The screens are 4 or 5 layers and appear to be held in place by a tiny retaining washer. I suspect that digging out the fine screen mesh may significantly damage it but that may be the next step.
I will try to get it apart again tomorrow and see if there is some bockage there.
It cranks and responds to throttle but 70 psi control pressure is, indeed, going to lean out the air/fuel mixture.
Took the CPR apart again and the screens are the only next step. The control pressure is reading the 70psi of the fuel distributor regulator which everyone seems to say is a sure sign of blocked screens. Since the original fuel issue was rust everywhere it seems appropriate to have a go at it even though failure here could be terminal for any potential rebuild.
I may have killed my WUR today.
With the unit disassembled on the bench I was able to force brake cleaner through the screens both ways. It leaked slowly inlet to regulator nozzle and I was able to squirt brake cleaner through from the nozzle side out with some force.
That had to mean that the thing was clean enough to pass gas but no such luck. Upon reinstalling the gauge was reading the 70psi system pressure. Took it off for the fourth time.
After debating with my self over some of my souvenir bourbon from the trip I got the pick out and dug out the screens. No saving them as they were firmly clamped into place. After carefully cleaning out all the trash that I could see, blowing with air gun and brake cleaner put it back together and back on.
Started right up with 22psi control pressure. I didn't wait until it went through the warm up routine. That would seem to be a clear indication that clogged screens was the issue.
Now I have to wonder if there is enough trash left in the system to foul up the regulation shortly. Failure symptom is running lean but it does run.
I am going to explore obtaining a bench rebuilt and tested WRU but initial searches put that as unlikely or expensive. A review of the rebuild kits determined that the only thing in the $50 kits of any value is the regulation disk. None supplied the nozzle or the filter screens.
Anyway, I think it will regulate through warmup and run now.
Found a company in Texas that rebuilds the WUR for under $200. Bosch does not appear to sell the critical parts outside their internal rebuild services. Wonder what the situation is with replacing the screens.
DeLorean Auto Parts -
https://www.deloreanautoparts.com/wa...egulators.html
Yesterday afternoon the control pressure cold and warm was just right. Engine warmed up to the middle of the temp gauge. I went out this afternoon with the intention of ending the detention on HF jack stands and found the pressure at about 10psi and a very rough idle.
Appeared that some of the destroyed screen is now in a critical point in the regulator. I just packed my WUR up in a box for an all expense paid trip to Texas.
Tired of screwing with it.
Off to see the wizzard!