Thread: WUR Problem?
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ossiblue ossiblue is offline
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Join Date: Oct 2005
Location: Capistrano Beach, Ca.
Posts: 7,235
Quote:
Originally Posted by Brian Fuller View Post
Constriction Test

1. Connect the CIS pressure gauge between the WUR and FD
Disconnected the main return fuel line fitting behind intake runner #3.
2. Residual fuel will flow out when you break this connection and be ready to have a piece of rag or a container ready.
Connected a temporary plastic hose for the return line from FD to a one liter bottle to collect the recycled fuel during the test.
3. Turned on FP and the bottle filled in less than 10 sec. Fuel pressure almost reached 4.8 bar
4. I tested return main fuel line to fuel tank by blowing air through line, I could easily push remaining gas in line through the tunnel fuel line and then could hear bubbling noise in fuel tank. (as part of restoration fuel tank was pulled and cleaned and new tunnel fuel lines were installed.

I now believe the constriction is at the WUR. Can a WUR get clogged internally?
Can you clarify something in your constriction test?

I believe, on your car, the return line from the WUR runs up to the rear of the FD where it connects with the fuel pressure relief valve. From there, both the FD excess fuel and WUR excess fuel share the same line back to the tank.

Your test description sounds like you disconnected this common return line without isolating the return line from the WUR. Because you got a rapid fill of your container from this return line and the fuel pressure did not change, only means the fuel was coming from the FD relief valve. Unless you isolate the return line that comes directly from the WUR and test to see if that line is blocked, you cannot tell if the lack of fuel flow from the WUR is from the line or the WUR itself.

If I misunderstood your post or your testing, I apologize. My main question to you is, have you tested the line from the WUR, in isolation, for blockage?

Edit: after rereading your WUR bypass test, it sounds like you did find fuel flowed freely through the WUR return line, but your description of the connections was confusing to me. If you made connections directly from the FD port to the WUR return line, and fuel flowed freely, then that does leave only the WUR as a point of blockage.
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Last edited by ossiblue; 09-03-2016 at 08:59 PM..
Old 09-03-2016, 06:46 PM
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