'94 7.3 Starting Problem (maybe)

[dzlwzl]

Hi all,

I think I have a hard start problem. I say I 'think' because I'm not sure if my expectation of what is normal is correct or not.

My (relatively new to me) 94 F250 is difficult to start anytime the engine is cold, whether the ambient temperature is cold or not.

I've had other diesels that started a lot easier when cold, with one or two cranks. But this one I have to crank 10 to 15 seconds at least, and I really don't like going over 5 seconds. So I usually have to do a series of 5 second cranks to get it started. The manual says I can crank up to 30 seconds, but there's no way in hell I'm going to do that.

I had the injection pump replaced last month because it was leaking, and they tested the glow system and replaced one bad plug. Other than that, it had a clean bill of health.

When warm, it fires right up with no problem.

So who has the starting problem, me or the truck? Should I just suck it up and lay on the starter for 30 seconds? That may be 'normal', but it doesn't seem 'right'.

['94IDITurbo7.3L]

what color smoke do you get when you crank the engine over?

sounds like it might be an air intrusion.

how many miles on the injectors? if the injectors have over 150K miles on them it would be highly recomended to replace them with brand new BB code injectors. don't get remans if you can help it.

if and when you do injectors get a new return line kit as well. that would be one of the most likely places for an air leak.

How long does the WTS light stay on for? should be ~10-12 seconds and then go out and start to click. what brand of plug did you use for replacement. anything other than motorcraft/beru's don't last real long and have th possibility of swelling and then tips breaking off and falling down into the head. don't want to scare you, just making you aware if you don't know.

welcome to the forum.

[dzlwzl]

Thanks for the reply.

Originally Posted by '94IDITurbo7.3L

what color smoke do you get when you crank the engine over?

sounds like it might be an air intrusion.

It will just puff white smoke while I'm cranking it. The moment it turns over I get a burst of black smoke and it disappears almost immediately.

Originally Posted by '94IDITurbo7.3L

how many miles on the injectors? if the injectors have over 150K miles on them it would be highly recomended to replace them with brand new BB code injectors. don't get remans if you can help it.

No idea for sure. The engine shows 130k miles on it, which I believe are original. I assume a bad injector would throw an error code though.

Originally Posted by '94IDITurbo7.3L

if and when you do injectors get a new return line kit as well. that would be one of the most likely places for an air leak.

I forgot to mention that the return line was replaced when they replaced the IP last month. The return line was leaking before it was replaced, and the problem got a little better after it was replaced.

Originally Posted by '94IDITurbo7.3L

How long does the WTS light stay on for? should be ~10-12 seconds and then go out and start to click.

That sounds about right as far as the time. I don't know about the clicking though. I'll have to listen for it the next time I start it.

Originally Posted by '94IDITurbo7.3L

what brand of plug did you use for replacement. anything other than motorcraft/beru's don't last real long and have th possibility of swelling and then tips breaking off and falling down into the head.

The replacement plug was motorcraft, but the other 7 weren't. They tested the glow system however and found everything to be ok, so I didn't have all the plugs changed. I wasn't planning to have them changed but I happened to have one spare plug in the center console and when they told me one was busted I told them to put it in.

I've been adjusting my starting ritual and it seems to be getting slightly better when I hold the accelerator closer to the floor while cranking. Previously I was only holding the accelerator half way as per the manual, but when I go almost to the floor it seems to start in 3 or 4 seconds most of the time.

However even doing that, it still is hard to start if I leave it sitting for a long time. Over Thanksgiving I didn't drive it at all so it sat over 24 hours and it was a PITA to get started.

['94IDITurbo7.3L]

Originally Posted by dzlwzl

I assume a bad injector would throw an error code though.

nope on the error code. these engines are mechanically injected. no computer to control or monitor injection. since they have ~130K miles on them i would take them all out and get them pop tested for proper opening pressure and spray pattern.

were is the timing marks on the injection pump lined up at? there will be a line on the pump gear housing and on the pump itself. you can line those marks up to get a decent baseline setting. then you should try to fine a diesel shop that acctually knows what they are doing and have it dynamically timed with a timing meter. might want to try advancing the timing for right now. loosen up the three nuts that hold the ip on and rotate the ip towards the passenger side fender. move it while the engine is off. tighten it back up all the way when you start it as well. move it in ~a dimes width increments and retest. could also put some clear plastic tubing in place of the return lines to check for air leaks.

[powerstrokemonster]

i would also diffently have injectors tested if not replaced also as stated above advance the timing alittle. i would also check the fuel heater on top of the fuel filter housing and make sure that is also working good luck