Hello All,
I am going to look at a 1990 F-250 with a 7.3 diesel engine in it. What should I look at in this engine? I have never delt with this engine before. The guy says that the engine has 100,000 miles on it and would this milage be a problem? Also, what kind of milage do you usaually get with this engine? I am looking to drive about an hour each way for school. Would this engine do that? And, in Ohio winters can get bad, what is the proper way for starting it in the winter?
Thanks,
Chris

 

[updated:LAST EDITED ON 21-Aug-02 AT 08:14 AM (EST)]>Hello All,
>I am going to look at a 1990 F-250 with a 7.3 diesel engine
>in it. What should I look at in this engine? I have never
>delt with this engine before. The guy says that the engine
>has 100,000 miles on it and would this milage be a problem?
>Also, what kind of milage do you usaually get with this
>engine? I am looking to drive about an hour each way for
>school. Would this engine do that? And, in Ohio winters can
>get bad, what is the proper way for starting it in the
>winter?
>Thanks,
>Chris


Those engines should go at least 300k if maintained properly. If it gets really cold where you live put in a block heater if the truck doesn't already have one and cycle the glow plugs before starting.

Les

 

Ok, LEs thanks alot. I hope that it was maintained properly.
Thanks,
Chris

 

 

You may want to ad some radiator additive to protect from Cavitation erosion. This is caused by air bubbles traveling in the cooling system and chipping away metal. You can find it from Caterpillar or I believe NAPA.
The stuff works and should be followed with enhancement additions of the same product.

 

>Those engines should go at least 300k if maintained
>properly. If it gets really cold where you live put in a
>block heater if the truck doesn't already have one and cycle
>the glow plugs before starting.
>
>Les


Hey Les. Thanks again in advance for your constant input to my questions. Could you explain what you mean by "cycle the glow plugs". Is it that you wait the entire 2 minutes before attempting to start?

John

 

A lot of people "cycle the glow plugs" by turning the key on, then when the light goes out they turn it off, then back on. The probelm with that is that when the light goes out, the plugs are still on. They can stay on up to 2 mins after you turn the key to on. The light is just an indicator of when the air in the cylinder "probably" is warm enough to start. The light takes a reading from the air intake temp sensor and judges how long you ought to wait before cranking. It isnt even hooked up to the glow plugs or the relay at all.

So basicly 'cycling the plugs' does absolutly nothing but reset the timer for the light. On cold mornings I turn my key to on, finish puting stuff in my truck or what ever, then crank her over and let it idle a few minuts.

 

On my diesel, the "Wait to Start" light is the time it takes for the glow plugs to warm completely. After they warm, the computer pulses the relay to keep them warm for up to a minute whether i start it or not. Even after i start it they continue to pulse for about a minte. i don't think it has to do with cylinder temp.


STEEDA (powered by Ford)
93 Mustang GT STEEDA

1994 Ford F350 Crew Cab LWB 7.3 Turbo diesel
352,000 miles and using a bunch of oil, but runs great!!

 

No, not the actual temp inside the cylinder. What I meant was that the computer gets the temp of the outside air from the IAT (intake air temp) sensor and determines how long to keep the glow plugs lit inorder to allow it to start. You can watch your gauge to see when the plugs shut off cause it will jump to the middle. When they are lit you can see from the gauge that it's drawing power big time.

Well, that's how it is with a Powerstroke anyway.

The main thing I wanted to get across is that a lot of folks dont realize that the 'Wait to Start Light' is not always on when the plugs are. Watch your gauge to determine when they are lit and when they arent. Turning the key on and off again wont shut the plugs down and "cycle" them, it will only restart the timer for the 'wait to start' light.

 

>Hello All,
>I am going to look at a 1990 F-250 with a 7.3 diesel engine
>in it. What should I look at in this engine? I have never
>delt with this engine before. The guy says that the engine
>has 100,000 miles on it and would this milage be a problem?
>Also, what kind of milage do you usaually get with this
>engine? I am looking to drive about an hour each way for
>school. Would this engine do that? And, in Ohio winters can
>get bad, what is the proper way for starting it in the
>winter?
>Thanks,
>Chris

See if he will let you take an oil sample and send it to black stone.
http://www.blackstone-labs.com/

 

[updated:LAST EDITED ON 02-Nov-02 AT 06:43 AM (EST)]The IDI's do not have an AIT sensor, what they have is a sensor if you want to call it that mounted on the GP Relay, which is mounted on top of the glow plug controller. It's nothing more than a large spring looking resistor, it reacts to air temp on top of the engine, and as current flow thru it (while the glow plugs are cycling) it's resistance value changes, so then this causes the glow plug controller to sense a difference in the voltage so it just starts turning the glow plugs off and then on again. but anyhow... Just turn the key to run, wait for the lamp to go out, hit the starter. You will notice that the voltage gauge will continue to jump around, for about 1 min. This is normal and should be of no concern unless it does not stop firing the glow plugs. Now when you first start the truck when cold, the high idle solenoid will want to kick the throttle up, but under most cases it is not strong enough to kick it up automatically, so what I do is wait for lamp to go out, hit the starter, watch my oil pressure and when it comes up for about 2 seconds. I will bounce my foot off the go pedal to set the high idle. This solenoid will have enough butt to hold the idle higher while in the warm up stage, I let the truck run for about 30 seconds this way. Then just drive EASY until the water temp gets up to 150-160 degrees then I will allow the rpms to increase over 2k. Does not take long, but allows the engine to warm up before seeing higher rpms.
One of the things that you want to verify is was the anti-cavitation additive used in the truck. These early 7.3's are quite prone to the problem. Ask the previous owner about it, pick up some test strips from International or the like. Test the radiator yourself. Don't ask the guy over the phone, just show up on his doorstep to look at the truck, then pop the FW-16 (this is the ford part number for the cooling system additive) question, if he kind of looks like a deer in the head lights, then it more than likely did not get the treatments, but go ahead and test for it. If it's there then he probably had the truck serviced and only knew who to write the check out to. Getting the oil checked by Blackstone labs is a good idea. They are located in Fort Wayne, Indiana. But will test oil samples from where ever. Just get in contact with them thru their website or call them. They can tell you a lot about the truck just through the oil sample. 100k is something that a diesel can shrug off with style if it has been kept up maintenance wise.

Mileage will vary with how hard you put your foot into the go pedal. After 2000 rpms the mileage drops like a rock. Normally you can expect 12-17 depending on your driving style and rear gear ratio. I have never seen more than 14 out of the Enterprise, but then again I run 70-75mph with 4.10. And pulling my camper I will get 10-11, but again I run harder than most.

Block heaters help quite a bit, but I have not HAD to use mine. I think that they came stock on these trucks, but you might want to check.