Thanks Curley!!
On 12/26/2016 10:21 AM, Curley McLain via Mercedes wrote:
Basics:
0. put the charger on the battery to recharge/maintain it during a lot
of cranking.
1. Crack the fuel line(s) then crank to make sure you have fuel
delivery. About 720ยบ degrees rotation on the crank should be
enough. If you need to bleed the system, more cranking is needed.
2. If fuel is being delivered to the nozzles, Then proceed to
electrical checks
3. Key on to glow position, check for 12V at each GP. Be careful not
to short the probe to ground. You may need a couple of glow cycles to
complete this. A helper to turn the key to glow/off makes it easier.
4. Pull off the cover from the GP relay, pull the plug to the GPs.
If 0V on step 3, turn key go to glow and check for 12V on the relay at
the terminals for the GP wires. If 0V, replace fuses first, if
present. Otherwise, replace GP relay.
(a further test is possible to make sure the key is delivering juice
to the relay to turn on the relay. Consult wiring diagram for this
info) If a fuse is present, it is generally a fuse problem. if a new
fuse does not fix it, and GP, GP wires are good, it is almost always a
bad relay.
5. If all used relay pins are delivering 12V to the wiring harness to
the GPs, turn the multimeter to the lowest ohm reading you have. check
meter for zero. If you can't get 0, offet your reading by the static
amount. Check the used sockets in the plug on the GP harness between
one socket and ground. Book value is 1.4 ohms. 0 ohms is a open
plug, replace it. over 1.7 ohms os a bad plug, replace it, if you are
sure your meter is reading correctly. It takes a good meter to read
1.4 ohms. with a cheap ($10 HF) meter it is 0 or infinity, so if you
get something near 0 ohms, you assume it is good; infinity indicates
it is an open circuit, replace the plug. GPs usually fail open. A GP
with say 2.4 ohms reading is on its way out and needs to be replaced.
2.4 is about as high as I have seen. I have seen meters that
consistently read 1.7 on good or new GPs, so you have to learn your
meter's idiosyncrasies, unless you have a very expensive ($500+) meter.
You guys edit this to make this an all purpose troubleshooting formula
for non start or slow start Diesels.
Larry Turner via Mercedes <mailto:mercedes@okiebenz.com>
December 26, 2016 at 8:42 AM
No. i probably didn't explain the chronology very well.
1,. Tried to start it - had to crank excessively to get it to finally
start - .
2. After excessive cranking it started running very rough - exactly
like it would be when 1 or 2 GPs go dead.. (After your question
about the dash light I recalled it being illuminated while the car
was running.)
3. During this start up episode I noticed lots of white smoke from
the exhaust pipe.
4 Since I had 5 new GPs on the shelf I jumped in to R&Ring the GP
probably too quickly.
5 After replacing the GPs I tried to start it and it just cranked
over. Since I had removed the fuel lines to get access to the GPs,
I failed to bleed them after re-installation.
6 My next step will be to bleed the air from the fuel lines then try
to start it once more.
7. I will do the electrical tests suggested by Mitch to confirm my
relay has died. BTW, I checked the in line fuse just in case only to
find it perfect. I think there's a fuse across the bottom of the
relay but doubt it has gone bad.
_______________________________________
http://www.okiebenz.com
To search list archives http://www.okiebenz.com/archive/
To Unsubscribe or change delivery options go to:
http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
To search list archives http://www.okiebenz.com/archive/
To Unsubscribe or change delivery options go to:
http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
