How to start a 7.3 IDI

[BKahler]

What is the recommended starting squence for an IDI? Reading the info on the sunvisor it says when the temp is above 32 degrees to depress the pedal part way and when its below 32 degrees push it all the way to the floor.

Up until tonight the truck and been starting pretty darn good. After a 22 degree night it started on the send GP cycle. Made me quite happy. And while we were in Ohio I got to plug it in overnight and it started on the second spin of the motor. For the 3 weeks or so that we've owned the truck I've never had to cycle the GPs more than 4 times to get it to start.

So tonight I go out to start the truck and it won't fire. I keep trying and once in a while it will pop but won't catch. A couple of times I thought it was starting but then it stopped.

During all of this I can smell diesel. If it was a gasser I'd say the choke was stuck closed and it was flooded.

So how do I start this thing

 

[82fordtruck]

You're doing it right. That thing'll fire down to about -20 if all is right.

How long is the WTS light on?
Can you tell how fast it's cranking over?
Do the batteries and cables look good?

The WTS light needs to be on about 10-15 seconds, and it needs to crank like hell to fire. If it's not, look at the above items.

Alternatively, you can DISCONNECT the gp's, and fire it on ether, but do all this first.

 

[soulpatchfr]

sounds like you have glow plugs problems to me.
with a properly operating charging system & a good starter, these old girls will fire of in sub 0 temps on one cycle without the aid of the block heater.
(might not sound real happy about it for a few minutes, though)

if you can count the revolutions of the starter, you batts are probably low.

have you read through the FAQ's & tech articles yet? i can't swear to it, but i think you'll find some pertinent info up there.
Good Luck

EDIT: anyone else notice how a laptop keyboard elliminates letters out of words? i KNOW i typed the whole word!!!

 

[dbensen]

Sounds like you are having a problem with the glow plugs. On the 7.3 controller if even one GP is dead the system short cycles and will not allow the rest of them to heat up enough. I would first check that you are getting voltage to the glow plugs. I had a GP relay that made all the right noises but did not make contact inside. If the relay is happy check to make sure all the GP are good. My guess is that you will find one or maybe two that have failed. Let us know what you find.
Good luck,
Doug
'86 F-250 4x4
'89 E-250 ATS

 

[BKahler]

Thanks for all the quick replies. I just got the truck started. I had been trying to start it off of the front tank which is the tank we drove in on two nights ago. I had tried off and on all evening trying to start the truck with no luck. For some reason I decided to switch to the back tank and the truck fired right off. I won't say it was the first spin of the engine but pretty close.

I have a hunch there is a problem with the hose splice that I put in when I eliminated the inline filter during out trip. I think its probably sucking air when switched to the front tank. I won't have a chance to look at it until this weekend.

At least it started

You must be registered for see images

The first time I cycle the plugs in the morning they generally cycle for 8 to 10 seconds. The second and successive times the cycling doesn't last as long. The warmer the ambient temperature is the faster they cycle.

The battery cables all look good as do the connections. The batteries seem to recover quickly from being cycled a lot, at least they did this evening.

I'll see how it does over the next few days and report back.

Thanks,

Brad

 

[F350camper]

I don't know if, or necessarily think, this is your problem, but one often over looked reason for hard starts is a blocked or severely restricted return line. Just something to keep in mind.

 

[BKahler]

Glow plugs

Well, after trying to start it again tonight I paid closer attention to the timing of the WTS light. Ambient temperature of around 65 degrees and the truck hadn't been started since the night before. I turned the key on and the WTS light stayed on for no more than 4-5 seconds. Seems to me thats to short a period of time. I'm betting now that my real problem is I have some failed glow plugs.

Possibly some time this weekend I'll have a chance to check them out. I'll report back after I've done so.

Thanks,

Brad

 

[OkieGringo]

IF/WHEN you get a chance to pull the glow plugs, check to see what brand they are. If the are Autolite REPLACE THEM NOW. Since you recently bought the truck, the PO could have put in new Autolites and they are already dead or dying. Autolites are CRAP, especially in THESE IDIs. They might be good for a chevy 6.5 but if you leave them in this engine you'll be REAL SORRY SOON. Get Motorcraft ONLY at Autozone or where ever you can get them. OkieGringo

 

[f-two-fiddy]

You should only need 1 cycle of the plugs in your location. With a properly operating GP system. It'll never get cold enough, down there, to need more than that.

I fired my '85 @-20 with 1cycle. As stated, she sure didn't sound like she liked the idea, though.