lraffe1 Posted December 8, 2011 Share Posted December 8, 2011 i have a hard start 7.3. i suspect it is glow plugs or relay. i first stuck my test light on the relay and has power through it. i then test each gp at valve cover and lights on each one. i then checked amps and peaked at 198 then quickly dropped to 90 amps. i thought there was post in past about this but can not find it or remember if this is normnal. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 8, 2011 Share Posted December 8, 2011 Bruce has posted on this several times: ...Put an inductive clamp on one of the relay leads and have a buddy turn on the key. It should hit around 190 initially, and taper off to 125 after 15 seconds... Quote Link to comment Share on other sites More sharing options...
lraffe1 Posted December 8, 2011 Author Share Posted December 8, 2011 i used my micro vat and it was 198 then dropped to 90 amps Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 8, 2011 Share Posted December 8, 2011 i have a hard start 7.3. i suspect it is glow plugs or relay. i first stuck my test light on the relay and has power through it. i then test each gp at valve cover and lights on each one. i then checked amps and peaked at 198 then quickly dropped to 90 amps. It isn't your GP. Check your cranking speed on the scan tool, it should be 150+ cold and 175ish warm. They will sound fine at 135rpm and start hard. If that's OK (and other basics like FP, ICP, etc) your injectors are not atomizing correctly and it's time for a set. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted December 8, 2011 Share Posted December 8, 2011 If that's OK (and other basics like FP, ICP, etc) your injectors are not atomizing correctly and it's time for a set. It's getting to be that time of year that injector sets come rolling in. Nobody wants to believe it. Everybody automatically assumes the glow-plugs aren't working because the engines will start perfectly fine with the block heater plugged in. Don't forget how useful our ears can be for narrowing down possible injector issues by listening to them while running a buzz test. Quote Link to comment Share on other sites More sharing options...
lraffe1 Posted December 8, 2011 Author Share Posted December 8, 2011 i should have add truck is a 01 and only has 79705 on it. wouldn't think it would need set of injs at that mileage maybe one or two and some o-rings. it does have one oem battery and one red motorcraft batt. think maybe i will start there. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 8, 2011 Share Posted December 8, 2011 It's getting to be that time of year that injector sets come rolling in. Nobody wants to believe it. Everybody automatically assumes the glow-plugs aren't working because the engines will start perfectly fine with the block heater plugged in. Ditto, well stated. Originally Posted By: AlexBruene Don't forget how useful our ears can be for narrowing down possible injector issues by listening to them while running a buzz test. Yes, but that only determines if the magnet and armature are free and working correctly. If the barrel and plunger are worn/sticking/galled the buzz test will sound normal but the fuel may not be delivered/atomized correctly. If the armature is sticking causing a hard start/nostart, run the buzz test 3 times and see if the truck will start. Damon has a fix for those- pull the magnets off the injectors and clean around the armatures (the square steel plate) with brakeclean and air. The magnets have a tendency to build up metallic sludge, cleaning frees up sticking armatures/poppets and makes the truck start/run better for a while. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 8, 2011 Share Posted December 8, 2011 i should have add truck is a 01 and only has 79705 on it. wouldn't think it would need set of injs at that mileage maybe one or two and some o-rings. it does have one oem battery and one red motorcraft batt. think maybe i will start there. ANY 7.3 can need injectors at nearly ANY time, they are very susceptible to contamination wrecking the barrels and plungers. Mileage means nearly nothing. FWIW, look at MFDES hot idling. If it's above 12ish the engine is starving for fuel because of low FP or degraded injectors. Good Luck! Quote Link to comment Share on other sites More sharing options...
lraffe1 Posted December 8, 2011 Author Share Posted December 8, 2011 cranking rpm was 150. i test drove and got warmed up. i checked mfdes and is .13 grams hot idle. i also checked cyl perdel, 1 and 2 bouncing around 1%, 3 is around 2-3%, and 5 is 6%. also ran cyl con test and flagged cyl 8. also checked and oe battery only has 230 cca and motorcraft has 680 cca. thanks for the help going recomend a battery and retest and then see what he wants to do about injs. what do u gys think about the vavuum test for 7.3. is it worth the time it takes to use it properly. Quote Link to comment Share on other sites More sharing options...
Fordracer Posted December 9, 2011 Share Posted December 9, 2011 i should have add truck is a 01 and only has 79705 on it. wouldn't think it would need set of injs at that mileage maybe one or two and some o-rings. it does have one oem battery and one red motorcraft batt. think maybe i will start there. My own truck is a 2001 with 45,000 miles on it and it wont start below freezing without it being plugged in and the glow plug system is working properly. So the injectors can go bad with low miles. I haven't replaced them because I only use the truck for towing in the summer and it sits all winter unless I need to haul something. That brings up a quick question. When towing up a hill I can hear the "rattle" of the engine change and the check engine light will come on and give me a P1211 every time. The IPR goes up to 60 when it does it but the ICP pressure and ICP desired match. I put a stiffer fuel pressure regulator spring in it and the fuel pressure is 80 psi and I replaced the IPR and it still does it. I was going to test the low oil pressure when it does it but haven't got around to it yet. I assumed it might be the HPP but now I'm wondering if the injectors aren't atomizng correctly if this could be the problem. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted December 9, 2011 Share Posted December 9, 2011 I find most of the vehicles with full set injector failures are usually the ones running on long oil drain intervals. I am not a big fan of the "flush queens", but I have seen hot oil flushes alleviate some hard start issues. Quote Link to comment Share on other sites More sharing options...
lmorris Posted December 9, 2011 Share Posted December 9, 2011 Be wary of the flagged #8 injector. The new CMP can falsly set that. If you can, put in an old CMP and retest cylinder balance. Quote Link to comment Share on other sites More sharing options...
lraffe1 Posted December 9, 2011 Author Share Posted December 9, 2011 It seems like number 8 sets every time you run cyl contribution test. Its kinda like a p0340 code. You know its there, nbut is it false or caused by other concern. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted December 10, 2011 Share Posted December 10, 2011 Quote: I am not a big fan of the "flush queens", but I have seen hot oil flushes alleviate some hard start issues. You must be changing the oil in the HPOP reservoir also. (slight reference to the character in In Alex's avitar for those not in the know) Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted December 11, 2011 Share Posted December 11, 2011 I find most of the vehicles with full set injector failures are usually the ones running on long oil drain intervals. I am not a big fan of the "flush queens", but I have seen hot oil flushes alleviate some hard start issues. Ermmmm, I can remember back when a person who is significant in my life was having "hot flAshes"... that was....... interesting. Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted December 12, 2011 Share Posted December 12, 2011 No one has mentioned that fact that the diesel fuel we run these days is now Ultra Low Sulfur content and that we have lost the lubricity that these injectors were designed for. I definitely agree with Alex about the extended oil change intervals. And then there are the Scamsoil fanatics that believe in their biased oil analysis that that company provides. Jim can probably remember the 7.3L that I had come in missing on a couple of cylinders and popping through the intake. This truck was a Scamsoil victim for it's whole life with oil change intervals done between 15,000 and 20,000 km's with filter changes approx every 5000km's. The customer was preaching this shit to me and praising it up and down while he was standing there watching over my shoulder as I diagnosed his truck. The customer would send his oil out for the Scamsoil biased analysis and it would always come back good and they would just recommend a filter change. Anyway, when I pulled the Valve covers off, you couldn't see the injectors or any metal. Just black tar and mud along with two bent push rods and rocker arms with the tips worn right off of them. I had sent his oil out to Schell for an analysis and the customer sent out a sample of the same oil for his Scamsoil analysis. New push rods, new rocker arms and a couple of oil flushes fixed that truck up. And the look on the customers face when I showed him inside his engine was priceless. He came back to the dealership about a weak later for some more work to be done on the truck that I had quoted him for and brought his Scamsoil analysis to show me. What do you know? The analysis showed that everything was good and all they recommended was an oil filter change. Then I showed him my analysis. NOT GOOD! Everything was really bad on that analysis, but the one thing that I can really remember was the that the "SODIUM" content was through the roof. Like as if someone had dumped a bag of salt into the engine. Again, the look on his face was priceless. Then I faxed both analysis reports along with a letter explaining the whole situation of this truck to my brother in law who is a Scamsoil dealer and had constantly preached that shit to me for years and argued constantly with me about it. He doesn't preach to me any more. Thank God! Quote Link to comment Share on other sites More sharing options...
Fredsvt Posted December 13, 2011 Share Posted December 13, 2011 Dwayne I had a customer with a 2002 7.3 who fell victim to the same line of BS. He put their "bypass filter" kit, which gets rid of the large filter for two smaller ones. He followed their recommendations of using their "diesel rated" 5w30 and 50,000 MILE oil changes, and their anal-ysis. Always came back great. So he changed the filters every 15,000 miles, at their recommendation and added oil as needed. At 80k, he said it wasn't sounding right, a guy in our shop took a sample and sent it to another lab. They CALLED him and said the engine needs to be shut down NOW with how bad the wear metals were. It threw several rods and broke the crank at 82k. I won't even use that crap in my lawnmower. Quote Link to comment Share on other sites More sharing options...
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