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hello i have a 7.3 that will only start on the good stuff how do i narrow the problem down and how do i test glow pluggs kinda new to the diesel world
thanks joe
To test glow plugs: Take good test light and attach to + positive terminal on battery. Then remove wire to GP and touch tip, if tester lights then it's good.
How long does the WTS (wait to start light) stay on should be 10-12 sec. If it is shorter than that on a cold engine then some GPs may be toasted. Only use Mororcraft/Beru GPs get them from autozone. If you have Autolite GPs installed read http://www.members.shaw.ca/k2pilot/ for the good and bad news.
you are going to have one of two problems, or maybe 2? on start-up. Heat and/or fuel. No heat from GP's or no/bad fuel. You said "it will only start on the good stuff". What does that mean?
i checked all gp and found 6 to be bad with tips broken replaced all 8 with motorcraft gp from auto zone i drained the fuel filter and i tried to start wts light came on for bout 8 sec but truck was in a heated shop about 65 degs cranks fine but still wouldnt start i shot a quick squirt of starting fluid in it and it started right up blow out a bunch of black smoke i shut it down and it started fine without starting fuild i ran it for bout 15 min the smoke seem to clear out but it smelled real rich eyes were burning i watched the exhaust and every few seconds there was a little burst of white smoke seems to be ideling normal when replaceing gp should it start hard at first??
The running rich was probably all the fuel you had in the cylinders from when it did not start. Or have you changed the air filter recently? A dirty air filter will do the same thing.
Ether and glow plugs are a bad combination, one or the other should not be used.
When the glow plugs are working right, it should fire right up when the wait to start light goes out.
are you getting fuel to the injectors? Perhaps the on/off section of the injection pump is "off" all the time. Have someone crank the engine while you depress the valve in the shrader valve on the fuel filter housing. Fuel shud squirt across the engine compartment. If you get fuel there, move to the injection pump and have someone work the key, you should the pump click on and off. Then move to the injectors, crack the lines on top of few and see if you are getting fuel there. Even tho the truck is in the shop, try plugging in the block heater for an hour to help it start. BE CAREFUL with the starter, they are susceptible to heat damage from over cranking.
thanks guys all of the above help out it was the glow plugs and i was loaded up the pump was a little retarded so i advanced but over shot i fine tuned runs like a champ of cource i know gp and ether dont mix but when u need a wreaker u need a wreaker thanks again happy holidays to all