7.3 diesel. while i am in there

[T77911S]

my daughters f250 would not start at all last week with this cold spell so I am having to learn diesels and had to break down and work on it in the cold. finally got it started and in the garage thank goodness.
I could not believe it. I measured resistance from the wire for the glow plugs(GP) to ground and it was open. I did not trust what I was seeing as I could not see ALL 8 GP's being bad. so I dove in and pulled all 8. every single one was bad!!
so with all bad and it starting and running fine in "normal weather" I have to assume everything should be good? injectors? air leaks? and so forth.

so is there anything else I should look at while I am working on it?

already cleaned up the battery posts, I am running another ground form the battery directly to the engine and I am going to pull the starter and rebuild that.
trying to get it started it seemed like the batteries ran down pretty fast so I want to clean up the starting circuit.

I have read about injector O rings but from what little I have read they seem to be a pain to pull out and if it has been running good should I mess with it?

[Evans, Marv]

If the thing runs alright, I wouldn't mess with it & continue to do some research on your potential problem. After you find out what it is, then attempt a fix. I've got 175K on my '03, and so far have only had minor things other than routing maintenance. Good luck with your daughter's.

[LeftCoastErik]

replace the under valve cover harnesses. they are likely your problem.if all 8 are showing bad, its usually the GP relay. Ohm the GPs out directly (not through the harness) to be sure.

[speeder]

DO NOT pull the injectors just to install new o-rings unless there is strong evidence that one or more is leaking badly. The symptoms of that would be that it wouldn't run or would run extremely poorly.

They are not a normal, "while you're in there" maintenance item and the protocol for pulling them is involved. Removing them is no big deal but the issue is the HP oil system, (and a smaller amount of fuel), emptying into the cylinders and draining the system. Not a fun or easy job even if you know what you're doing.

You tested all 8 glow plugs independently outside of the truck and they were all dead? A little hard to believe but if you say so. If the truck starts ok w no glow plugs in warmer weather, you have good compression and a healthy engine. The batteries draining down rapidly while cranking it over is normal and another sign of good compression. It takes a lot of juice to spin over a 7.3 liter V-8 w 17.5:1 compression ratio.

The factory battery grounds are more than sufficient, just make sure the cables are good and connections not rusty. They already ground to the 800 lb. lump of cast iron under the hood, you are not improving anything by doing it another 1,2 or 3 times.

You do not say what year or how many miles it has but that could allow for some more specific advice.

[speeder]

Originally Posted by LeftCoastErik

replace the under valve cover harnesses. they are likely your problem.if all 8 are showing bad, its usually the GP relay. Ohm the GPs out directly (not through the harness) to be sure.

That's what I was getting at. I don't think that he actually tested the GPs, which has to be done on a bench w GPs connected to power directly. That's the most basic test. I don't even bother to test for resistance, it's so easy to see if one is dead or heats more slowly than the others.

[ckelly78z]

My 99 Powerstroke needs to be plugged in (block/fuel filter heater) for an hour minimum when below the freezing mark. I think I need a set of GPs...it will, however start instantly with a small quik shot of ether into the intake. I use Power Service DieselKleen 8-10oz in every tank of fuel which helps also.

Also check the age, and strength of the batteries, it is reccomended to replace both of them at the same time if they are weak, and go for the high CCA batteries.

[T77911S]

yea I did.
pulled all 8 and ohmed them out. every single one was OPEN.
i first ohmed from the GP relay to the engine,. i figured that if at least ONE was good i would have around 1-2 ohms but it was open.
yea, when i get symptoms like this i tend to question what i am doing.
had 12v on the GP side of relay, also measured current. had 8A on the blue wire but zero Amps on the 2 wires to the GP's.
i could not believe all 8 were bad so i had to go in and pull at least one side,. have all 8 out now.

really did not want to dig into the injectors now anyway. i have my BMW330 on stands with oil pan off and intake off and need to get that back on the road,

i was looking at the valve cover wiring. its pretty stiff.


i think there is a problem with the hydro boost.
when you start the engine then put your foot on the brake pedal it kind of kicks back a little.
a friend with an f350 had the same thing but i forget what she said it was other than it was expensive.
i am reading on rebuilding it but that is for a later time.

its a 99 f250 with 208k on it.

i just put in the 05-07 headlights for her. they look really good.

[T77911S]

i put 2 new batteries in it for her when i bought 4yrs ago.

i read ether is not good for it.??


next i plan on a 26 row tranny oil cooler,.

[ckelly78z]

Ether is not good for the lubricating properties of the oil, but gets you going (motor started) in a pinch. I change the oil immediately after Winter is over to prevent damage. It's the difference between driving home, and getting a ride with someone else.

[speeder]

Starting fluid or ether will do a lot more damage than polluting your oil. It should really never be used in anything you were not planning on rebuilding anyways. My '95 F-250 7.3 w mediocre compression started w no problem last winter after sitting out all night in 10deg weather not being plugged in. If your truck doesn't start w good glow plugs and good batteries, you should really figure out what's wrong w it.

An engine w almost zero compression will start w starting fluid. It's seriously something I'd only use in a life or death situation or on a blown engine. I use it on an old Benz when I have to move it but it needs to be rebuilt so who cares.

[pete3799]

I put GP's in the towns 7.3 F350 last year. 1 good one and 7 bad.

[cabmandone]

Originally Posted by T77911S

i put 2 new batteries in it for her when i bought 4yrs ago.

i read ether is not good for it.??


next i plan on a 26 row tranny oil cooler,.

I guess it depends on how much you like your intake. Ether in an engine with glow plugs likes to go boom. I'd say Ckelly's aren't working if he can spray it with ether. Get a 6.0 trans cooler, it's a great upgrade and pretty easy.
If you have the valve covers off, do the 50 cent mod for the injector harness.

[Arizona_928]

Not my 7.3, but my alh has no working glow plugs. Starts fine in normal weather, but it's cranking for the cold. My hmmwv has a couple bad glow plugs, but they're most likely swollen, and won't come out easy. So I just suffer.


As for your 7.3, glow plugs are a wear item. Especially since they're not the cremeric plugs

Yep! Ether and hot glow plugs will go boom.

[Grog]

I had a 93 & 99 7.3
On the 93 if one plug went bad, all current went to the remaining plugs. When you lose one plug in the bank of four, the other 3 are not far behind, burn too hot. I don't remember if this was the case for the 99 7.3 powerstroke.

[pen15]

Quick and easy test is amp draw. 20 amps per plug initially then quickly drops as they warm up. Can check one side at a time and know exactly how many are working.

[look 171]

I hear those things are a real btich to take out because they can break off due to dissimilar metal contact. I am dreading that day

[T77911S]

they weren't hard to get out.
I hear the AUTOLITES are very bad. they swell and you CANT get them out.

I plan on checking the current draw when I get them in. that way I can just clamp the amp meter back on in the future if I suspect they are bad.

going to get new valve cover gaskets with the wiring harness.

[asphaltgambler]

Pen15 is right. Its how we first determine the health of the glow plug system. When its cold; 30 degrees or lower you should see @ 200 amps total draw. If not, we plan to replace all 8 and the relay. THEN, once it starts it should run fairly evenly and be responsive to throttle input. If not.......

Then you'll need a scan tool to run basic KOEO / KOER tests to check the health of the injectors and high pressure oil system. DO NOT guess. All these parts are expensive to replace and you could actually introduce another problem chasing symptoms with parts.

[T77911S]

well when it rains it pours,.
got the BMW on stands, daughters truck is down, 930 tires are bald but I am driving it and NOW the wife calls me and the Mercedes tranny is acting up...AGAIN.
I had the valve body off about 6 months ago. replaced the conductor plate and took the VB apart and cleaned it up. shifted better than it ever has. wife drives it and its back to acting like the conductor plate is bad.
problem is MB said the trannys had lifetime fluid so nobody ever changed it. I have since drained and just replaced what fluid has come out several times now. there is still a lot of gunk in there that is getting on the conductor plate causing problems. I cant flush it because too many miles on it and at this point flushing will kill the tranny.
240k on the MB.

any ideas how I can do a home flush?
one time on another car I used the lines to the radiator. I opened one to an empty bucket and used the other feed new fluid in with the engine running.

oh yea, I think my Volvo tranny is going. sometimes slips when starting off. 210k on it.

[Oracle]

[QUOTE=T77911S;9877163 I could not see ALL 8 GP's being bad. so I dove in and pulled all 8. every single one was bad!!
[/QUOTE]

ah.. the joy of diesel engines.. (and the maintenance cost)
Brings back fond memories of when my wallet was fuller and I could afford it..

Now I do the same with Gas and I ain't going back.. even if I spend more on Gas.. The repairs, maintenance and headaches are similar until the frugging engine (especially Ford) needs a rebuild.. then with a little bit of math you realize it was not cheaper.. and you're still not seeing the end of it..