Question about a 89 F350

[austin7.62]

Hello, I have been lurking for a long time, but have finally decided to join. I have really a growing interest in the old IDI diesels, and I am wanting to pick one up. First off, I don't have much experience with diesels, but I have done quite a bit of research. So anyways, I am looking at a 1989 F350 DRW pickup, with the 7.3 IDI and Zf-5 transmission. It is 2wd, and has 4.10 gears. I would use the truck for working mostly. Hauling sod, gravel, lawn equipment. Anyways, I went to look at this truck today, and I really liked it. Cosmetically, it has virtually no rust, just a bit of surface rust from use. It only has 131k miles! Mechanically, it seems to be in good shape. The owner has installed an aftermarket temp gauge, and it never got above 190 when i was driving it. It also seemed to have a good clutch that starts grabbing near the bottom of the floor, which I like. It doesn't have any strange vibrations or noises. When I was driving it, the power seemed good, and it idled smoothly. So all is going well on the test drive, but as I was about to turn off onto the owner's street to take the truck back to his house, it just died as I was slowing down. No warning, no rough running, nothing. It just died! I had put the truck into neutral as I was coming to make the turn, slowing down without engine braking when it shut off. I kept it in neutral, and turned the key, and it fired right up, no problems. It didn't run poorly after it shut off either. The owner said I probably let the clutch out too soon, but all I did was put it in neutral. He wasn't really paying attention anyways. What could cause this? Like I said, there was no indication or warning, it just happened. I did notice that the fuel was low, maybe a little under 1/4 of a tank. I'm going back and forth if I should get this truck or not now. To me, it seemed like a nice truck, but I don't want to buy it, just to put thousands of dollars into it right off the bat. I know it's old, but still, you hate to buy something and not be able to use it immediately! So, I guess in a roundabout way, I am asking for advice on what I should do? I really have a lot of respect for this community, and I need your help! Thanks!

 

[austin7.62]

Also, one thing that I noticed is, that the AC pulley would occasionally seem to seize up, but just for a second, and go back to turning. The owner said it was because the defrost was on. Is that true? Thanks!

 

[The Warden]

Welcome aboard!

Did the engine die immediately after you shifted out of gear, or was it idling in neutral for a few seconds before it died? If it died immediately, it might be a stuck metering valve in the injector pump...doing a few severe overdoses of PowerService fuel additive should help clear the metering valve out and resolve the issue; I would also replace the fuel filter. 9 times out of 10, that'll resolve a stuck metering valve. However, if that's the problem and the fuel additive doesn't take care of it, you might need an injector pump, which will cost money to buy and $$/time to install and properly set the injection timing.

I don't think the low fuel level played a role here; if air had been sucked into the fuel intake, the engine wouldn't have fired back up immediately as you described. It would have taken 10 to 15 seconds of cranking to get the air out of the fuel system.

I tend to think you should go for it; maybe try to claim that the engine dying is a symptom of a failing pump and use that as leverage in negotiating price. But, any used vehicle is a potential gamble...

Also, one thing that I noticed is, that the AC pulley would occasionally seem to seize up, but just for a second, and go back to turning. The owner said it was because the defrost was on. Is that true? Thanks!

Define "seize up". The outer pulley should never seize up (if it were, you'd hear belts squealing); however, the hub in the center is a clutch that will stop rotating with the engine when the a/c clutch is disengaged. When the air conditioning is on, the a/ cclutch cycles between on and off to maintain pressure. And, yes, when the defroster's on, the a/c is turned on...this is done to dry the air that's hitting the windshield. This is the case in any vehicle; the a/c will be powered on and the compressor will cycle as I described, but the heater core puts out enough heat to counteract the a/c cooling the air...so, in this case, the a/c only acts to remove moisture from the air.

 

[austin7.62]

Thanks, Warden. It died pretty close after, or immediately after I put it in neutral. If I get it, I will do the fuel additive stuff to see if it remedies the problem.

Ok, so from what you described with the a/c means that it was working fine, there was no squealing or anything like that.

 

[austin7.62]

Ok, so one thing the owner told me today is that if you keep your foot on the pedal slightly, it won't have a problem. He said maybe it's a idle control motor? Sound right?

 

[icanfixall]

As already mentioned... Welcome to the forum. The rig sounds like a good deal. As for the engine dieing don't worry bout it. You can easily turn up the idle setting with a screw driver. Please ask before you do messing with mechanicals. We can guide you as if we were standing there next to you but fixing a problem you made cause you did not know what was inside that "thing" is never fun. I suspect it has original injectors and injection pump. Sadly they wear out around this mileage you posted so expect maybe on replacement in the future. Not difficult or expensive but asking for help solves those newbie problems we all made long ago. The cleanup suggested in the fuel is a great idea. If you decide to change the fuel filter any time soon just fill it with the cleaner and run it for say 2 minutes and shut down till tomorrow morning. Sitting in the pump and injectors will surely clean the parts and possibly make things run correctly.
There is no telling what may break next week either but knowing this going in helps. Please do not buy the cheapest ebay parts until you ask here about the sellers. We have a forum called... The Hall of Shame. Those listed got there because they cheated some folks here.


No such thing as an idle motor and something may be wrong with the ac system. No way will the pulley stop turning becaise the defrost is on. Since about 1968 ALL US cars send ac air to the windshield defrosters for DOT safety. If vacuum fails to the small vacuum motors that direct the air when on heat or defrost or just air with fail directly to defrost.

 

[Lifted Mudder]

Is the pulley seizing up or is the electric clutch in the center of the pulley stopping. The pump will stop under normal use when the LP sensor is triggered because condenser temp. is down. If it is short cycling it is probably because the condenser is dirty and not getting enough air flow or the refrigerant charge is low.

 

[whiteboyslo]

I'm guessing the 'seizing' is actually the clutch engaging/disengaging. A real seize would be....bad (like 'throw the belt bad'). Perfectly normal if the AC is on and/or the defrost setting is on, but otherwise it shouldn't be happening. If it's doing it a lot, it either means your charge is low or you have a faulty switch (low pressure switch?). Mine would cycle all the time even after the shop charged it. They replaced some switch that cost me all of $15 and it's been fine ever since. Still cycles, but nowhere near as much.

Mike

 

[riotwarrior]

As already mentioned... Welcome to the forum. The rig sounds like a good deal. As for the engine dieing don't worry bout it. You can easily turn up the idle setting with a screw driver. Please ask before you do messing with mechanicals. We can guide you as if we were standing there next to you but fixing a problem you made cause you did not know what was inside that "thing" is never fun. I suspect it has original injectors and injection pump. Sadly they wear out around this mileage you posted so expect maybe on replacement in the future. Not difficult or expensive but asking for help solves those newbie problems we all made long ago. The cleanup suggested in the fuel is a great idea. If you decide to change the fuel filter any time soon just fill it with the cleaner and run it for say 2 minutes and shut down till tomorrow morning. Sitting in the pump and injectors will surely clean the parts and possibly make things run correctly.
There is no telling what may break next week either but knowing this going in helps. Please do not buy the cheapest ebay parts until you ask here about the sellers. We have a forum called... The Hall of Shame. Those listed got there because they cheated some folks here.


No such thing as an idle motor and something may be wrong with the ac system. No way will the pulley stop turning becaise the defrost is on. Since about 1968 ALL US cars send ac air to the windshield defrosters for DOT safety. If vacuum fails to the small vacuum motors that direct the air when on heat or defrost or just air with fail directly to defrost.

Idpe air control motor Gary is on gassers...there is such a thing....just not on our trucks engines. It is technically an idle air control valve...but often talked about as motor...

 

[riphip]

Where are you in TN. I'm in Memphis

Rick