Quote:
Originally Posted by darkman
Following Brian's instructions I tried to test like this:
Tested battery got a 12.5v reading.
Then while in #2 key position placed black to ground and red to
the glow plug (touching the exposed plug right below the head)
I got no reading at all.
My test meter instructions say use black for the -pole so I did
it that way (taking from the +/- discussion that it doesn't matter).
Did I do it right?
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No. You should be testing the glow plug for resistance. On your meter there should be a scale for Ohms. You select the low end of the available ranges of Ohms (on my Sears model 982406 the choice is 0-200 Ohms). Then, you unplug the connector between the glow plug relay and the glow plugs. The relay is located on the left front inner fender, near the top. It is a black plastic box, that has a kind of flip top that comes off. You open the box and will see a typical six pin electrical connector plug. You have to work it a bit to get it off the mating connector, and I don't recall if the part you pull off has the pins or the sockets. In any case, each pin or socket is the end of the wire going to a specific glow plug. When you test you look for resistance from the pin or socket to ground. The circuit includes the glow plug. One of the halves of the connector has an identifying number cast into the black plastic adjacent to each pin or socket, so you can know which plug you are testing.
Alternately you can check from the threaded end of the glow plug to ground, which can be any convenient surface on the engine or head.
Quote:
Originally Posted by darkman
I didn't test the old ones for resistance because I'm not sure
how to do that. I know I can find the instructions via the search
function so I'm doing that now.
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If the plug is out of the engine, you check resistance again, but this time between the end that has the electrical connection (on older cars this is the small threaded end, and a smooth pin on newer cars) and the large threaded surface that engages the threads in the cylinder head.
Quote:
Originally Posted by darkman
other question:
Manifold was removed but not the injector lines. It was
incorrectly reattached and 3 lines are bent significantly and
one is pushed out of place so that the clip won't reattach. None
of them are broken though.
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It is not a good idea to bend them at all, and then to leave them essentially unsupported is asking for a fatigue failure from engine vibration and the pump pressure pulsations. So, I would try to either coax them back into their original orientation and fit the clamps and fixtures to them, or replace them. Sorry. Others may disagree, and I have no specific analytical engineering basis for my concerns - just practical experience.
Good luck, and post back when you get the results of the RESISTANCE checks for the glow plugs. Once you have that data we can go into measuring voltage. The way you had the probes positioned you were measuring the voltage difference between the ends of a copper wire, which should be zero unless the wire is way too small for the current being passed. Jim
__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles
Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)
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