NarfBLAST
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Part 3 of 3
Back to School Tune-Up Part 3 of 3 - Injection Pump Case Relief Valve
I remember Windex, when he did my last timing belt, showing me this valve and how the guts like to slide out of it over time. I did some research and it turns out that case pressure is used to advance timing when requested. That could be my problem right there! This seemed like an easy thing to check, but it would involve "opening" the injection pump, so I would have to be meticulous - which is always exciting!
First I cleaned the external part of the valve:
Then I realized that neither my crows-foot or other wrenches would be able to loosen it. I figured I would have to make my own special tool - which is always exciting!
It took a few trips to the vice to get it ground out enough to slide down nicely:
Its always fun and satisfying to make your own keys to open things you are not supposed to open:
You know the fit is good when you can stand the tool straight on head of the bolt, at an angle to vertical, and it doesn't fall over:
Anyway, the relief valve guts had indeed started to slip out:
So I tapped them back in flush:
And I went for a test drive, with no change in my symptoms. Bummer.
I went back and read Jeff's email again:
"Logs look good except for some missing boost and timing. It may be struggling to lift/deliver fuel from a clogged fuel filter", was the first line in his email.
It was at that moment when I realized I should check when the last time the fuel filter was changed. Turns out it was changed last spring, just as I had vaguely remembered, but what blew me away was that I had put on 50,000 km since then! The fuel filter is overdue and could very well be the source of my lack of case pressure and lack of timing advance!
I can not prove this theory until my shipment of fuel filters (qty. 2) arrives later this week.
If there had been a fuel filter on the shelf I might have changed that first, but instead I went around the long way eventually circled back to the first thing I should have done. Just another reason to always have extra filters on hand. In hind-sight I remember thinking, "hrm, check the fuel filter, okay I don't have spares so I guess I will move on to the next thing on the list, dumb dee dumb." And I didn't even bother to check my service history because I figured, "I just changed that last year anyway."
The other funny thing is that I have had clogged filters give me symptoms of reduced top end power before, so I should have known better.
I'm hoping its the fuel filter, but I have also ordered some fuel line because the stuff between the filter and pump looks cracked and the clear plastic part looks kinked and also there are sometimes streams of bubbles.
Either way, the car runs great and pulls harder than before, and I have an endless supply of stuff to tinker with. The fun never ends.
Back to School Tune-Up Part 3 of 3 - Injection Pump Case Relief Valve
I remember Windex, when he did my last timing belt, showing me this valve and how the guts like to slide out of it over time. I did some research and it turns out that case pressure is used to advance timing when requested. That could be my problem right there! This seemed like an easy thing to check, but it would involve "opening" the injection pump, so I would have to be meticulous - which is always exciting!
First I cleaned the external part of the valve:
Then I realized that neither my crows-foot or other wrenches would be able to loosen it. I figured I would have to make my own special tool - which is always exciting!
It took a few trips to the vice to get it ground out enough to slide down nicely:
Its always fun and satisfying to make your own keys to open things you are not supposed to open:
You know the fit is good when you can stand the tool straight on head of the bolt, at an angle to vertical, and it doesn't fall over:
Anyway, the relief valve guts had indeed started to slip out:
So I tapped them back in flush:
And I went for a test drive, with no change in my symptoms. Bummer.
I went back and read Jeff's email again:
"Logs look good except for some missing boost and timing. It may be struggling to lift/deliver fuel from a clogged fuel filter", was the first line in his email.
It was at that moment when I realized I should check when the last time the fuel filter was changed. Turns out it was changed last spring, just as I had vaguely remembered, but what blew me away was that I had put on 50,000 km since then! The fuel filter is overdue and could very well be the source of my lack of case pressure and lack of timing advance!
I can not prove this theory until my shipment of fuel filters (qty. 2) arrives later this week.
If there had been a fuel filter on the shelf I might have changed that first, but instead I went around the long way eventually circled back to the first thing I should have done. Just another reason to always have extra filters on hand. In hind-sight I remember thinking, "hrm, check the fuel filter, okay I don't have spares so I guess I will move on to the next thing on the list, dumb dee dumb." And I didn't even bother to check my service history because I figured, "I just changed that last year anyway."
The other funny thing is that I have had clogged filters give me symptoms of reduced top end power before, so I should have known better.
I'm hoping its the fuel filter, but I have also ordered some fuel line because the stuff between the filter and pump looks cracked and the clear plastic part looks kinked and also there are sometimes streams of bubbles.
Either way, the car runs great and pulls harder than before, and I have an endless supply of stuff to tinker with. The fun never ends.
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