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7.3 f350 satrting issue

brian falcone · 2010-07-03 15:04

have a 1988 ford f350 dump. allways started right up after the glow plug light goes out. one day it started to act up. only starts with a shot of ether now. put in new glow plugs.new filter,cleaned out the fuel lines and last week we had the injector pump rebuilt. still only starts with ether. once it starts it will run all day and start on its own but let it sit more than 4 hours and you need the can again. my father put an electric fuel pump on the line and it still didnt help. any advice? im guessing low compression at this point. also we have the same issue with another truck we use for plowing. same motor...same problem

Replies22
  1. #1bpogue2010-07-03 16:39

    Have you tested the glow plug relay? They are known to go out on those motors. Also, be sure both batteries and all connections are good. Even though it sounds good, sometimes you just don't have enough speed to get them started.

  2. #2brian falcone2010-07-03 17:12

    relay never looked at the relay. ill try it tomorrow. the engine seems to turn over fine. but ill put it on the cgarger overnite and check all the connections too. im not upset at rebuilding the pump for no reason as we plan on keeping the truck anyway. but im stumped. it was fine one day then bad the next. brian

  3. #3willie592010-07-03 19:10

    Yep, definitely check the glow plug relay operation. Those model 7.3 had pre-combustion chamber heads, they won't fire a lick unless glow plugs are operating, even on a hot summer day. :yup

  4. #4spitzair2010-07-04 01:14

    My dad's 7.3 in his '95 F450 had this happen lots of times. It was always the glow plug relay as Atco and bpogue have said. If I remember right it's under the lid where the fuel filter is, just to the front of it, but it's been a long time since I looked in there... Pretty easy to change, last time I did it took about 20 minutes and good as new. Hope this helps.

  5. #5OCR2010-07-04 01:45

    7.3 f350 satrting issue: Picture could be better.... ​ OCR

  6. #6willie592010-07-04 09:59

    Now hang on fella's, your describing a turbocharged direct injection 7.3, the Powerstroke. Brian said his was an '88 model. That one should be the non-turbo pre-combustion chamber head engine. If my memory serves me correctly, that engine should have the glow plug relay at the rear of the engine located in the center similar to the old 6.9 engine.

  7. #7OCR2010-07-04 17:16

    7.3 f350 starting issue: Woops... this kinda reads wrong. I meant... picture could be better, because it's a lousy picture, not that it's better than your description, spitzair. Well... how's we doin' ? Such a stickler for details, geez... :tong Well, it's like a bear trap, so it probably does... Guess we gotta come in for "slapin' time" again, huh?... OCR... Oh, and happy Fourth, ATCO and All... :thumbsup

  8. #8willie592010-07-04 18:09

    OCR...you sure you ain't related to Archie Campbell? You can twist up a conversation worser than (or, is that gooder than?) the master. :tong YouTube - Tribute to Archie Campbell

  9. #9John C.2010-07-04 19:01

    I had one of those in a service truck once or twice. It is a timer relay and it's directly behind the air filter housing and part way down the back of the block with the fire wall just above. It's not bad to get to and change. It is expensive and you have to check all your glow plugs again. If you have a bad one the extra current through it will burn out the relay again. Don't ask me how I know. On my 6.9 I just did away with the thing and hooked a push button in the cab to it. Now I know the things are getting the juice they need to start the engine. The 7.3 has different plugs and I think the relay is solid state so you may not be able to do that. Good Luck!

  10. #10OCR2010-07-04 19:05

    7.3 f350 starting issue: Lol, well, I could be... but I done lost track... :tong Heck ATCO... lernt that from an Uncle. YouTube - FESTUS PARTS THE WATERS OCR... :lmao

  11. #11OCR2010-07-04 21:03

    7.3 f350 starting issue: Back on track. Oh... one more thing. I believe my friend ATCO, sent me that YouTube link, in a PM. Gotta give him credit... OK, back on track... OCR...

  12. #12willie592010-07-04 21:45

    Yup. Once, your spelling got crazy, I asked if you was kin to Festus. Figured you was having a hard time spelling 'cause you never learned to read the readin'.

  13. #13brian falcone2010-07-04 23:15

    relay will look into the relay.its a non turbo 7.3. ive seen the push button mod,for the glow plugs on another truck before but i cant recall when or where

  14. #14willie592010-07-05 00:16

    As JohnC stated, the early 7.3 used a solid state relay, seems it was 100 bucks or better. They were bad for crapping out. I suppose one could retrofit a standard relay solenoid operated by a pushbutton on dash, just never done that myself.

  15. #15Dozerboy2010-07-06 21:30

    We have switch our over to push button its been a while. But IIRC wire them in with the factory resistor. The 6.9's and 7.3's use 6 volt glow plugs, not 12 volt plugs. Many people wire them up with a FORD starter solonoid and a switch inside the truck, but this results in fried glow plugs on a regular basis. If you run the stock glow plugs, ONLY USE BERU GLOW PLUGS! The AUTOLITES are known to swell and break off inside the pre-chamber as well as the BOSCH plugs. If your going to a manual switch, run a FORD starter solonoid and run AC 60G's for a 6.2/6.5. The 60G's are a 12 volt self regulating plug and will thread into the ford glow plug holes.

  16. #16willie592010-07-06 21:56

    Wow, I did not know that Dozerboy, dang good info there. :notworthy

  17. #17truckboy2010-07-16 01:45

    1. check to see that engine has not jumped timing( especially the escort) next my suggestion would be completely drain carbs and tanks ( will these start on starting fluid?). check distributor cap for carbon tracks or moisture. how do these engines sound while cranking? possible stuck exhaust valve or blocked exhaust( rodent nest in exhaust or engine)

  18. #18Digger Dan2010-07-16 06:41

    Good batteries are essential too, losing 10 to 15% of capacity on the batteries can affect starting though it sounds like not in your case. I aM on my third 7.3 turbo diesel vehicle now and love the engine, but I did have starting problems with one of my previous trucks, new batteries cured it for me, it sure takes allot of juice to get running when its cold.

  19. #19qball2010-07-16 23:27

    ummm, yeah, the 7.3 used a holly carb. never saw a 7.3 in an escort. as for the distributor, it is actually in the oil pan so it is real hard to check.

  20. #20mitch5042010-07-16 23:58

    Hey Q, I think it's one Holley and one Rochester; but my money's on the rodent.

  21. #21stuart olson2010-07-17 00:51

    hell your both wrong they came standard with six stromberg 97's and a 6-71 blower

  22. #22soso2010-08-02 12:52

    if you go direct with a push switch make sure glow plugs are 12 volt and not 3 volt you dont want to melt the ends off have you tried pluging in block heater to see if this helps also check for air in fuel 6.9 and 7.3 were bad for this likly sources of air intrusion is water seperator on fire wall and small return line on top of injuctors a good way to tell is to remove small line off fuel filter plug port put small line in a can with fuel start and see if you get any airbubbles in can good luck tom