TOP END REFINISHING

[Schrade]

Voltage check.

Charging terminals in battery (with hose @ hand )



jumper



didn't budge for 5 seconds, no noise, nothing - then, 5 seconds later, a light click, and

[Schrade]

Un-plug, and it started to fall. Post 3 minutes, it was under 20 PSI.

No fuel anywhere. Stuck my schnazz in the valley, in the rail connectors, no fuel smell.



The lines were DRY - un-plugged both ends for 2 weeks. ALL air.

[Schrade]

It went to 0 post 15 minutes.

Second test pump #1; went to 52 again much quicker, and heard the pump.

10 seconds; power off. Drop rate much slower - post 3 minutes, it's steady at 24.

15 minutes post power down; still @ 20.

Test 3rd time shortly with stopwatch.....................

"""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""

Test 3:
Power off
0:15 - 44
0:30 - 40
0:45 - 39
1:00 - 37
2:00 - 34
5:00 - 28

Getting better each time.

Q: Where does the air go, that was in the line???

Does it get pushed to the tank? Does any remain in the INJ's, or rails, until it's run??????????????

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++

Should I test until I get no leakdown?

Or go ahead and test with both pumps?

OR,

Test pump 2 isolated?


Test 4; identical readings.
&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

So I held the guage pressure relief, and bled air, till it ran no air.

5th test; identical readings @ 15, 30, and 45.

If the primary pump has a check valve integrated (and it's blown), then another test WITH pump 2 + pump 1 should yield identical results, with the [blown] primary check valve still leaking.

I had good static pressure before this plenum pull

So now, if pump 2 can be tested in isolation, I can find out if pump 1 has a bad check valve.

Hopefully, it does NOT, and one of the injectors is leaking PROBABLY because a pintle is jammed open. Pulling each spark plug and checking for fuel should confirm this.

Thoughts????????????????????

Hello?

[Schrade]

Ok - I had (relatively sure hereof) a blocked OPEN check valve in the tank.

Test:

Both fuses in.

Power to test terminal.

Pinch feed line BEFORE rails inlet.

Power off test terminal. Pressure held @ 52.

Release pinch on rail feed inlet. Pressure dropped IMMEDIATELY ~12 to 40.*

Test again, NO PINCH, power off.

Pressure dropped VERY SLOWLY:
0:15 = 48
0:30 = 47
0:45 = 47
1:00 = 47
2:00 = 46
5:00 = 45

*This QUICK reverse flow MUST HAVE pushed SOMEthing [obstruction / sticking check valve] back OUT OF IN-TANK CHECK VALVE.

Could this be ANYthing else???????

[Franke]

Schrade, I would repeat this test a little more. After assembly of plenum chart A-7 on page 6e3-a-29 may help you diagnose if this is a this fuel pressure problem. I'm sure you have or had air in the system so the screwy readings. May still have a little air in there yet. The fuel from the tank goes to the fuel rails first and then to the regulator and then back to the tank. There is further testing with caution on testing the regulator in this chart and return fuel line pinch. I really don't think you will have an issue if all the air is out.

[Schrade]

This is the post I was referring to here Franke...

Give it a read through if ya' got a moment; and comment???

Originally Posted by Schrade

Ok - I had (relatively sure hereof) a blocked OPEN check valve in the tank.

Test:

Both fuses in.

Power to test terminal.

Pinch feed line BEFORE rails inlet.

Power off test terminal. Pressure held @ 52.

Release pinch on rail feed inlet. Pressure dropped IMMEDIATELY ~12 to 40.*

Test again, NO PINCH, then power off.

Pressure dropped VERY SLOWLY:
0:15 = 48
0:30 = 47
0:45 = 47
1:00 = 47
2:00 = 46
5:00 = 45



* This QUICK reverse flow MUST HAVE pushed SOMEthing back OUT OF IN-TANK CHECK VALVE.

OR

UN-stuck it, to free range of motion of the check valve...

Could this be ANYthing else???????

[Bearly Flying]

Nice to know I'm not the only fumble fingered one on here.....

It's looking Great, Keep up the good work.

[Franke]

I'm thinking more like your fuel supply was not able to function correctly with air in the system and by doing the pinch - release - re-pressure you purged the system and regulator of air. Based on the fact you had good pressure before disassembly it had to be something introduced afterward. Maybe I'm off on this thinking. Also, the fuel pumps feed do have a sock on them to prevent dirt introduction but I have seen the socks deteriorate over time on older cars.

[Schrade]

Originally Posted by Bearly Flying

Nice to know I'm not the only fumble fingered one on here.....

It's looking Great, Keep up the good work.

Thanks there BF; feelin' good about this, but still I have reservations about the 'hesitation', coming off idle.......................

[Schrade]

New test; pump #2 fuse pulled:

power up = 52
0:15 = 47
0:30 = 46
0:45 = 46
1:00 = 46
2:00 = 45
5:00 = 44

second test, I pinched the feed line (I don't like the idea of 'pinch')...

then released, and re-tested

power up = 52
0:15 = 49
0:30 = 48

and it held 48 after 5 minutes

me diggin' that in a BIG way