[mpost3r]

Hi,

I've got a 97 f250 ECLB 4x4. While I'm pretty mechanically sound and would like to think I know a bit more about cars than the average person, I'm relatively new to diesels (~2 months experience, 1 month of ownership of this current truck). These are my concerns (only engine-side; the rest of my issues I can pinpoint because other vehicles have them too) that I'm having with my engine. It's got 330k, bone stock (it looks like the turbo and downpipe have been replaced), and it makes typical 7.3 5 speed power, and gets 20mpg highway. It'll still get up to ~93mph until I run out of gearing, too. So the engine's not "unhealthy." I've cold started it(plugged in) at 10 below and it took maybe 2 seconds of cranking and it started right up.

-I'll be the first to admit it: I accidentally put regular 50/50 ELC in my overflow tank, and wouldn't be surprised if I mixed it. I'm gonna do a water pump and Tstat soon and a full coolant flush and then run a ~65-35 mixture of fleet charge. This is temporary (less than 3 months)

1. Temp Guage doesn't move
Granted, I bought this thing in the dead winter in Colorado and it's been -20F almost every day here. I keep it plugged in to keep some heat in it. However, I took it on a 4 hour road trip and it did GREAT, but the temp guage hardly EVER went past the "n" on normal. It only went to the middle climbing a mountain pass and went right back down as I let off throttle. I will soon replace water pump and put a 203 thermostat in it. I wonder if it's just cuz it's a really beefy cooling system or just because I haven't driven this truck in any weather higher than 35F.

2. Stiction?
Prev owner said the glow plugs were replaced. My coworker has informed me that often times people will only replace one bank because the other is hard to access. I wonder if this is the case. When not plugged in, at ~10F, it still starts within a couple seconds of cranking, but the injectors are LOUD and the entire truck shakes. The rear wheelwells rattle like there's no tomorrow. Changing to a 5-40 T6 oil helped this issue, but it still did it occasionally. I don't really cold start it unless it's plugged in for a while. Just wonders if I should try to address dirty injectors.

3. Lumpy Idle, only occasionally
Just cold started it tonight after sitting for 2 weeks in -20 weather, plugged in. No stiction, and it idled quiet and smooth. After 10 minutes of driving, when I idle again, it's kinda lumpy. I wouldn't call it a surging idle, it's a little slower than that; the exhaust sounds fine but the engine rocks a little bit and moves to a 1,2,3,1,2,3,1,2,3 kinda rhythm when it's normally 1,2,3,4

4. LOTS of eye-burning, white smoke ONLY after excessive idling in cold temps ONLY when revving engine in neutral
Again, this might just have to do with temperature. My theory is that the temp is so cold and the cooling system goes so hard that I'm cooling off the cylinders. Just tonight(and many other nights) I was slowly creeping around parking lots for ~7 minutes looking for a parking space, and tried to test this theory. I revved the engine to about 2300rpm and it was smoking a bunch. Fuel smell. Does this every time I excessively don't put load on the engine for a long time. Never rolls coal or white or blue under load, though. It burns clean. It DOES smoke pretty white and sometimes slightly mixed with blue on a cold start, but only for 5 minutes and it's gone when I start driving.

5. Throttle response?
This one might just be because I'm new to diesels and the compression is INTENSE, especially with a manual trans. But I feel like I can't really get driving around unless I'm like 40% throttle. If I'm driving in the mountains and let off for a hill, it takes quite a bit of throttle input for the injectors to start firing again, and when they do, it's not gradual. The injectors are just kinda on and off. It leads to jerky throttle applications.

6. BLOWBY
When it's cold, it smokes out of the oil filler hole as well as the dipstick tube. It's just a little waft of very atomized oil. Flipping the cap upside down it does not move at all, and holding my hand over the filler hole yields no excessively bad pressure. It's there, but for 330k, my dad's 80k mile kia has 3x worse.


Sorry this was so long worded, but I figured I might as well get all my engine questions answered. I very well might be just super paranoid, and I know I'm a bit insane for buying a diesel in the coldest area in my state, but I still know that something isn't 100%, but also know that such an old clapped truck will never be 100%. Any input, whatsoever, when it comes to repairs, things to look for, maintenance, etc would be GREATELY appreciated.

Thank you all for your time,
Sean

 

[1Dieselman]

I think that once you install the 203* a lot of your issues will go away. All diesels need heat in them to run efficiently. With little heat in the block and extreme cold being pulled into the cylinders it will not do a complete clean burn. 7.3s don't have stiction issues but you should use something like diesel kleen power service fuel additive on every fill up. White bottle for winter, silver bottle for summer. Throttle response is not great on a 7.3 in stock form as it is and a cold engine is not helping. The little blowby you have I would not be concerned with but when that engine that gets up to a normal operating temp you may see a little more.. I would get the thermostat changed along with maybe changing the coolant to something like 50/50 fleetcharge and see how it runs afterwards.

 

[fa35jsf]

I agree with most of what the guy above said. The only difference is 7.3s do suffer from stiction, being a HEUI injection system. Thermostat and water pump may help. Make sure you do a complete flush, meaning remove the block drains on either side on each flush, otherwise you are only getting half of the coolant.

Also, if after you do this and your water gauge still doesn’t move much, don’t forget it could just be the sensor on top of the water pump itself. That was my issue.

Throttle response. Check to see if it has a tuner plugged into the PCM. It’s by the parking brake.

And if you change glow plugs you should do all of them. It’s not that hard to get to them all. Also, as most would advise, only use genuine motorcraft glow plugs or a premium name brand. Many folks have had issues with the tips on the cheaper glow plugs breaking off and then you got a chunk of metal flying around inside your cylinder.


Sent from my iPhone using Tapatalk

 

[mpost3r]

I agree with most of what the guy above said. The only difference is 7.3s do suffer from stiction, being a HEUI injection system. Thermostat and water pump may help. Make sure you do a complete flush, meaning remove the block drains on either side on each flush, otherwise you are only getting half of the coolant.

Also, if after you do this and your water gauge still doesn’t move much, don’t forget it could just be the sensor on top of the water pump itself. That was my issue.

Throttle response. Check to see if it has a tuner plugged into the PCM. It’s by the parking brake.

And if you change glow plugs you should do all of them. It’s not that hard to get to them all. Also, as most would advise, only use genuine motorcraft glow plugs or a premium name brand. Many folks have had issues with the tips on the cheaper glow plugs breaking off and then you got a chunk of metal flying around inside your cylinder.


Sent from my iPhone using Tapatalk

thanks! and yeah, if I ever go into the valve cover to do anything, I'm replacing all 8 glow plugs with genuine motorcraft ones, regardless of if I think the ones currently in it are in good shape, as well as replacing the valve cover gasket and wiring harness. A new temp sensor is on the list as well, cuz parts are so cheap on these trucks.

I will check to see if there's a tuner plugged into the PCM, I doubt it but next time I'm at the truck I'll make sure to look!

 

[mpost3r]

I think that once you install the 203* a lot of your issues will go away. All diesels need heat in them to run efficiently. With little heat in the block and extreme cold being pulled into the cylinders it will not do a complete clean burn. 7.3s don't have stiction issues but you should use something like diesel kleen power service fuel additive on every fill up. White bottle for winter, silver bottle for summer. Throttle response is not great on a 7.3 in stock form as it is and a cold engine is not helping. The little blowby you have I would not be concerned with but when that engine that gets up to a normal operating temp you may see a little more.. I would get the thermostat changed along with maybe changing the coolant to something like 50/50 fleetcharge and see how it runs afterwards.

Alright, thanks!

That's pretty much my plan of action. I have a bottle of hot shot's secret diesel extreme that I run in every tank so far, and I'll have to do some more driving and run it through more tanks to see how well it works. And as for the coolant, 50/50 actually doesn't work where I'm at, as it will still freeze. Hence why I was going for ~65/35. Probably will end up around 60/40. My plan is to drain radiator and degas bottle, top it all up with distilled water, run it, rinse and repeat until I am draining nothing but distilled water. Then I'll change water pump, t stat, hoses, and fill with fleet charge.

 

[Raze9740]

I was having the same symptom with the temp gauge, did a thermostat (190* plan to do a 203* at a later date), still didn't register temp, put a new cap on the reservoir and now the gauge works. I don't ever reach the middle of the gauge unless i'm going up a long grade though it's been cold here in OR lately too.