I bought a 1989 f350 dually with the 7.3 idi banks turbo a few weeks back. I drove it 75+ miles home and have been dairying it around town since with no problems from the engine. For the last week I have been using wmo for fuel and it had been running great. I took it for a drive today and after about 15-20 min of freeway driving it stopped accelarating. Luckily I was right by my exit so I was able to get off the freeway, once I was off I was coming up to a stoplight so I put it into neutral and it instantly died. I got it to the side of the road and popped the hood. There was light smoke coming from the engine bay but nothing of concern. I did notice it was quite hot though, one of the first things I did was check oil and coolant levels, both were good, the weird thing is that there was a decent amount more oil than there was the day before. I let it sit for a hour and half and it started right back up. I finished the remanding 10-15 min of my drive (all country roads) with no problems. Then I went to go back home, when I started it up it sounded like it was almost misfiring, but it wasn’t too worrying. I got through all the country road portion of my drive no problem, but after about 5-10 min of freeway it started to lose power again and started smoking. I started to pull to the side of the road and again as soon as I put it in neutral the engine died. I popped the hood and it was really hot. I let it cool down for a bit and tried starting it but it just cranked and cranked. Again I checked coolant and oil, and the oil was even higher. Yesterday the oil level was about a eighth of a inch above the lowest acceptable level, and now it is about a eighth of a inch above the max fill line. I am kinda stumped on what could be happening. I was thinking injection pump or injectors because of the increase oil level and missfire, but I don’t feel like that would cause the overheating issue. Any ideas of what could be causing these issues?

 

Did your temp gauge or over temp light say you were overheating?
Historically, IDIs only weakness is air in the fuel system. Stalling while driving indicates an airleak between the gas tank and the lift pump. Do you have an electric lift pump or the mechanical lift pump on the passenger side of the engine?

 

rising oil level when driving is a sign of a bad diaphragm in the lift pump pumping fuel (or in your case waste oil) into the crank case.

 

Agree with above, likely cause of rising oil level is the lift pump. If youre running straight wmo, its thicker so maybe the extra pressure caused an already old lift pump to give out.
Less likely cause is the IP

 

My temp gauge doesn’t work, I was working on fixing it but now I need to figure out what’s up with the engine. I think I have a electric lift pump but I will check when I get home. Is there a way to test if the lift pump is bad? Also would a bad lift pump cause the overheating issues? I have talked to some people who think I have 2 separate issues but I think that it has to be 1 issue because it only shuts off when it overheats. I get home in a few hours and am going to do some digging around to see if I can find anything out of the ordinary.

 

always start with fixing what you KNOW is wrong. Thats ur gauge, then we are pretty sure your lift pump is leaking. If your lift pump also leaked diesel then that would thin your oil out. Too thin and you will have overheating issues.

 

I would usually agree with fixing what you know is wrong first but without the engine running there isn’t a point in a temp gauge. Once I get the engine running I will definitely fix the gauge. I just got done looking under it. I found that I have a mechanical lift pump but it has been bypassed using a smaller belt. Is this a bad thing? I am pretty sure that it is a fuel issue at this point but that still doesn’t explain the overheating. I am running almost 100% wmo so I don’t think thinning out the oil is the problem. If it is a leak in the pump could it be causing the engine to run lean thus overheating?

 

i don't understand you statement the lift pump being bypassed with a smaller belt.
the lift pump is bolted to the passenger side of the engine, between motor mount and front of engine.

if the lift pump is pumping WMO into the oil pan due to a bad diaphragm, it could overfill and cause engine to do strange things.
if it is indeed overheating i would not run it more than 2-3 minutes trying to figure out why.

 

if you suspect that it’s overheating, you should fox the gage first before even running it and since it seems like you have to run it a bit before reproducing the symptoms, running it just long enough to warm up isn't enough. so start with what you know is wrong.
very curious to know what is bypassed, vaccum pump im guessing? You have hydroboost?

 

Okay, sorry for the confusion, it is my vacuum pump that is disconnected which now makes me realize why my brakes are so hard and my ac doesn’t work. Does anyone know what size belt I need for it?
I haven’t ran it since yesterday when it overheated the second time. I am currently charging the battery’s so I should be able to get it started tonight. I’m not going to drive it at all just see how it runs and if I can see any issues while running. If it is the pump should I get a new one? Or should I buy a block off plate and go to a electric one? I am worried that the pressure from the wmo is what could have killed it and I plan too continue running it on wmo. I would like to keep my cost as low as possible but also don’t want to have to replace my lift pump multiple times. Also is there a way I can know it is for sure the pump before I buy a replacement?

 

shouldn’t have the same problem with a new pump, I like the mechanical pumps for the same reason I like this engine.. its mechanical. Some like the electric pumps but I don’t know how they are with wmo, probably fine?
as far as testing before replacing.. right now you HOPE thats the issue because of not then you need to r/r the IP. If you actually overheated.. you could have bad head gaskets and if water gets in your oil (I doubt this because you likely would have seen the milky oil when you checked your oil) then it can raise your oil level as water sits on the bottom. So all things considered, lets cross our fingers that the lift pump solves all your problems.

 

Napa says part number UNR 257320

alternator to vac pump

Still pretty common belt, like others have said fix your temp gauge or install a cheap aftermarket one. Heck, even an infrared temp gun on the rad can work in a pinch.

 

To answer the belt question, its a smaller belt that runs from the alternator down to the vacuum pump, and only goes between the two. I believe the belt is a smaller width than the other V-belts. Yes that would definitely affect your brakes and where the heater fan blows (it won't cause the AC to not work, but could default to all air running up through the defrost vents). Any auto parts store should be able to look up the belt for your (and any useful parts store should have it on hand..) However there may be an issue why that belt is missing. Have you tried turning the vacuum pump by hand? It may have failed and trashed the belt, or froze up and the previous owner pulled the belt. After I had converted my '88 to hydroboost, the vac pump started seized up and was making a hell of a noise. I thought that was mostly cable control for the heater, so didn't care when I pulled the belt and never fixed it. Something was still vac powered, maybe the recirc flap? AC didn't work so it didn't affect anything else.

Lift pumps fail, it may have nothing to do with running wmo. The one I replaced was pretty straight forward and cheap. It could definitely cause the engine dying and the oil level rising. The only way to know if someone added an electric fuel pump is to trace the lines from the tank all the way to the fuel filter on the engine.
When you were having problems did you notice if the fuel filter light came on? Not the water-in-fuel light light, the fuel filter one. It will come on when vacuum is pulled in the filter housing, which can be caused by a clogged fuel filter, or in my case, a dying lift pump not providing the necessary flow to the filter. I saw the light fading on with increased speed, then fading off when returning to idle. Then one day it stalled out of the blue when the lift pump completely died. In my case the diaphragm was fine, but the arm fell off when removing it.

Whether or not the lift pump has anything to do with overheating is up in the air at the moment. Without a working temp gauge, or using an infrared thermometer to get some readings, the description you gave said you're only guessing its overheating. These engines can push some heat if they are working hard, especially on a warm day. How you KNOW is was overheated? Was coolant blowing out the overflow hose? Where did you check the coolant level? The overflow tank is a good place, but only if you know the radiator is properly filled and the radiator cap and overflow hose works. I hope you didn't pop open the radiator cap on an "overheating" engine, that can be extremely dangerous and cause serious burns if the coolant blows out on you and flashes to steam. If you popped the radiator cap and it wasn't blowing out and flashing to steam, it probably wasn't overheating.

One thing to note about the oil level, it will be different on a cold engine versus a hot engine. The larger amount these engines take expands a good bit when warm. The proper way to test is to get the engine warmed up, then turn off and wait about ten minutes for it to drain back to the oil pan. I don't know the exact amount it will change, but it shouldn't be the amount you said it changed.

On another note, I know you said in your other thread you were pouring the oil through a pillowcase to "filter" it as a test. It wasn't clear if you ever set up proper filtering. I'm hoping you refined your procedure before going 100% WMO, otherwise you will quickly wear out the injection pump and/or the injectors.

 

and depending on the ambient temperature where you are, waste oil can get thick and kill a pump easily.
that is why most alternate fuel systems have heaters in them to bring oil temp up to flowable temperature.

 

The vacuum pump seems to be in good working order. I will definitely be getting a belt soon because right now my brakes are as stiff as a rock.
The engine definitely overheated because there was coolant coming out of the overflow tank and all my fluid levels were good. Luckily I think the head gasket is fine because I have no milky oil or oily coolant. I didn’t notice any dash lights on except for the engine light that has been on since I bought it. I’m not sure what code it is though because I can’t find the port anywhere. I checked under the dash and found what I think is the big connector but can’t find the other wire that I need. I am still using the pillowcase for filtering however it should be getting the oil down to about 3-5 microns so I don’t think it will harm the injection system. I do have my actual filtration system almost done but since the truck isn’t running I kinda put it on hold for now. I live in Washington so it isn’t cold here right now, I will definitely be getting a tank heater for winter though. The lift pump is pretty cheap but looks like a pain to get too, does anyone know around how long it will take me to replace?