How to make your 7.3 liter IDI cold start like new

What you need to do to make your old diesel start like it is new

[@MrGLADIATOR5100]

Air intrusion in the fuel system is the biggest one, that's where a lot of people find trouble with starting.

[@joeolvera333]

I have a 7.3 idi. Replaced everything and when I go to start I still get click, click , Click no glow plugs coming on. Any idea .

[@MrGLADIATOR5100]

@@joeolvera333 Is it cranking over? You probably have a bad glow plug, the gp solenoid kinda "gives up" if you have even 1 glow plug that isn't working.

[@blindmotorhead]

Nice old girl you have there, I am a person who is totally blind, but I buy vehicles that I like to have people, especially friends and family take me around in, hoping to get one of these one day, thanks for sharing the old girl with us.

[@TheUnsureFox]

I have one of these beauties as well, and she starts up just fine no matter how cold it gets. It really does boil down to the condition of your glow plug system, your batteries, and your starter. Mine starts even better than ever with a new starter on it! Reliable old engine. Never leaves me stranded.

[@mikecorleone6797]

I just ripped out my glow plug relay and wired my glowplugs directly to another starter solenoid and a push button and it works flawlessly.. even down to 16* weather i only need to hold the button for 4 or 5 seconds and she’ll kick right off

[@owencrow4432]

My 6.9IDI had a fuel delivery problem. Fixed that, new glow plugs, new relay, new starter. Boom, starts right up no problems.

[@mikecorleone6797]

That trump sticker though. I see you’re also a man of culture.

[@t.s.tractorworkstrickland5828]

I have three of these trucks at 86 a 93 and a 94 they all crank extremely well I don't use a glow plug controller just to push button. and also use the newer model powerstroke starter that spins it a lot faster I have no problems I love the trucks

[@ami2evil]

People talk shit about them because they don't have crazy HP numbers, and they think only new, overpriced shit is "good"... Too bad these are "better", and don't need a thousand sensors to run... The world is full of idiots, and when shit hits the fan, these will be around and the plastic garbage ran by a computer won't be...

[@luckyred1818]

I have several idi. U don’t need glow plugs above 70f if everything else is in spec

[@stevendausel643]

I had lots of trouble with my 86 with a 7.3 idi. After installing an electric fuel pump, GM 60G glow plugs that I modified, and got rid of the solid state glow plug relay and wired up my GP relay to a push button I have not had a single problem with it. Nice thing about the GM glow plugs is they are constant duty 12 volt glow plugs that can be powered up for hours and not burn out unlike the motor craft 6 volt glow plugs that burn out constantly.

[@AtomsForFuel]

The GM 60G look the same as the motor craft ones. are the threads the same? How did you modify them and what’s the difference between the GM 60G and the motorcraft ones?

[@jadinzack9271]

@@AtomsForFuel what he said

[@The73idigarage]

It's not the miles on the relay, it's the heat to the controller. I've been runnin the same controller since Aug 2023, had to replace the relay after 4½ months. New plugs & relay starts 1st cycle everytime. Relocated my controller to my fender

[@chewy-bu1oy]

Iv never had a problem with any of my 7.3idi diesel but I put new glow plugs and the relay some people would rather use starting fluid

[@davidlink8454]

Starting fluid will ruin your glow plugs... I'd suggest using wd40

[@chewy-bu1oy]

@@davidlink8454 ya iv tried using wd40 and it never works so I always make sure the glow plugs gets changed and the block heater works good

[@hitnrun1805]

Mine, the o ring on the hard-line between the filter head and the IP disintegrated and I had plenty white smoke out the tailpipe but no start. Thought it was the plugs, turned out to be the 8 month old compression rings. Got some rubber grommets from Lowes and they worked just fine, seem better than the compression garbage I was sold.

[@Jay-jb8lb]

Thank you brother for sharing a much appreciated very very explanatory thanks again have a blessed one

[@terrygriffith7907]

i put a case backhoe starter on my 7.3 idi it starts a lot better

[@t.s.tractorworkstrickland5828]

Part # please

[@terrygriffith7907]

@@t.s.tractorworkstrickland5828 SND0027

[@Roost426]

Put a new set of motorcraft glow plugs and a new controller in my 86 6.9, its the older style controller from the 7.3 one and screws into coolant passage on the drivers side head. It got to 11 degrees here a few days ago and it fired right up after 1 cycle and I hadn't even plugged in the block heater, also using 15w-40 conventional. I am running 2 Deka 850 cca batteries and a Denso gear reduction starter. Another thing that can make these grumpy to start is air intrusion into the fuel system causing it to lose prime, usually its the return lines, orings and caps on the injectors that like to start leaking.

[@sterlingwitherspoon5709]

Don't forget good fuel return kit

[@jeremiah6081]

Did you ever take out the restrictor plate in the Air cleaner ? Makes a big difference in HP

[@user-vx5gv7ig1c]

Моторчик красиво работает

[@user-ol5rd4dr1f]

no one seems to know that once the glo plug light goes out , you have to step on the fuel pedal once or twice,,,that kickes the engine into high idle & changes the timing., then crank it & she,s running..

[@2ndspingarage]

If it's above 32 degrees, mine starts pretty easy if I cycle the how plus 2 or 3 times.

[@jacobadams2885]

Dose your relay tic after wait to start is off? Mine dose but even in the cold it starts great. But some people say it means that the glow plug system is messed up.

[@RockyMountainHunters]

Usually it’s always glow plugs and the glow plug relay in the old idi’s. I’m a diesel mechanic and that is the most common issue. I also own a 6.9 idi. I replaced my glow plugs and the relay, threw in new batteries and a starter and she starts first crank after one glow plug cycle

[@nicholasjopin477]

Yes thats normal that means the the magic black box is working

[@jerrykeith1922]

I bougjt a 93 the other day. It starts fine cold but wont start after it has ran 10 plus miles. Let it cool down and hour or so it starts again

[@jsh111]

I've got a similar issue with my 93. Ever find out what causes this?

[@That6.7dually]

i have a 7.3 idi n/a and mine had a leak in the fuel line causing air to get in the line and make it run like absolute crap. still having a starting issue. its 70-80 degrees though, so thinking its the battery.

[@michaeledge6423]

You people make things complicated. I have a 1992 f-350. Glowplug relay doesn't work,not one glowplug works . It's a Ford people. I added 4 more ground wires to starter and engine block and plug in block heater at night when it's cold.it starts on second revolution every time . ford's need a badass ground

[@306-fromthestix]

I'm looking at acquiring a 1992 f150 with a 7.3 idi non turbo swapped into it with new glow plugs and ready, new clutch with single mass flywheel with a z5 transmission and 3:55 gears ..Any thoughts?

[@ami2evil]

Do it...

[@AtomsForFuel]

Did you ever get it and how mich

[@306-fromthestix]

@@AtomsForFuel no, it was a bad time,, diesel and fuel was climbing through the roof so I went with a vw tdi for fuel mileage

[@306-fromthestix]

@@AtomsForFuel the nearest town from me is a 32 mile journey one way

[@bradenmarkezich3961]

Any issues with the oil pump, or know how hard it is to change one?

[@davidlink8454]

It's right up front, easy to change

[@Wolf-fp3hi]

​@@davidlink8454 he said oil pump not vacuum pump the oil pump is in the oil pan and most the time there's no room to drop the pan with out pulling the engine

[@christopherlegg4494]

Temature

[@361almaraz]

😂 at .22

[@christopherlegg4494]

What empathetic you calling a cold start