Exactly why I started making videos! There's a lot out there that suck! I'll never say mine are the absolute best, but I try. Comments like yours keep me motivated to make more content.

I like realism in my videos 🤣 I imagine you got a laugh out of the pressure test failing on me the first try as well 🤣

Thanks! I do as well, I own 2 of them for a reason.

Thanks! Yes, very dirty. I would keep it plugged in any time im not using it, but after doing the math on what it costs, I decided against it a long time ago. I'll definitely keep it rolling until the cab rots off the frame!

My says plug it in 3 hours b4 you leave,what's the length you can leave it plugged in time wise ?

3 hours before you plan on starting it is usually sufficient to get it started and have pretty much instant heat in the cab. If you don't mind paying the extra electric bill, you can leave it plugged in 100% of the time you aren't driving it. As long as your cord is in good shape, it won't hurt anything besides your wallet. A 7.3L block heater draws 1000 watts, which means it uses 1 kilowatt hour (kwh) of electricity per hour. If you look at your electric bill you can find what you pay per kwh and multiply it by how long you want to leave it plugged in, then decide how much you want to pay.

You're welcome. Thanks for the compliment.

How did it turn out for you? This video was the 2nd time I'd done this job on this truck because I cheaped out on the oil cooler.

Glad you liked it! It's definitely not a fun job.

Thanks! I've never used any "flushing" products, I've just always used tap water, then one final flush with distilled water since tap water can have a lot of minerals and stuff in it that can cause corrosion. Whenever I do another coolant flush on one of these trucks I'll definitely be making a video on it, but as of right now I've never filmed it. I didn't actually do a flush after I finished this job. I managed to drain enough goo out that the little bit that remained in the system floated to the top of the coolant bottle, and from there I just used a suction gun to draw it out as it appeared. If it was a customer vehicle I would have flushed it for sure, but it's one of my trucks so I knew I could get away with doing it that way.

I've heard of people doing that. It definitely would give you more room. I guess I've just been lucky enough to get them out easy enough that in my mind it wasn't worth the extra work.

Dude it's a 7.3 it will run on anything 😂

@@bobobrazil1973 Pretty much! And thanks to a buddy of mine's truck, I've also learned that apparently they really don't need any oil pressure either! His truck for some reason would drop to, at most, 5 psi at anything over about 1000 RPM (never did figure out why), did that for a several thousand miles, sold the truck, and last I knew it was still going. It has 238/100 injectors and he wasn't nice to it either. 🤣

I would imagine that trucks and busses would be much easier. I'm sure there is WAY more room to get that thing out of there.

That's what I get for having pretty much the cheapest torque wrench possible! It is accurate though, I will give it that.

I try to keep my channel PG-13, so those parts get cut out haha. If I didn't edit the way I do, my channel would probably be rated R.

🤣🤣🤣 Sounds like you have some turbo and hpop leakage going on too!

🤣🤣🤣 I left that in the video for a reason! I wanna say I did the same exact thing on my turbo rebuild video. Now I have to go look. 🤣

I must have not left it in that video, I just looked. 😂

Got a good chuckle out of that as well 😅

Yes oil and rubber don't get along. About 3 months after this my upper rad hose blew out pretty spectacularly 🤣 Coolant does work as a lubricant, in the cooling system, not so much on bearings that are supposed to be in oil though 😆

@@darkhorseautoanddiesel you still own this 7.3?

@@repairvehicle Sure do. Got around 530k miles on it now.

@@darkhorseautoanddiesel , what repairs have you done to the engine? Any blow by? Original transmission? I’m thinking about getting one of those 7.3.

The engine itself, as far as I can tell, is all original. Blowby is at normal levels. It actually has slightly less than some engines I've seen with less than half the miles. I've had it out of the truck once, but that was only to replace the rusty oil pan. While it was out I did some freshening up to other components, like rebuilding the turbo (no problems with it, just figured I'd do it since it was already off the engine, also installed an upgraded compressor wheel), new exhaust manifolds, fuel system orings, and a new oil cooler (which is the bad one in this video). Probably a few other things I'm not remembering as well. Definitely not the original trans. When I bought the truck (had 314k miles on it at the time) the previous owner told me he had it rebuilt around 100k miles prior. I ran that one for about 50k more miles (I think, I'd have to look at my maintenance log), at which point I pulled the pan to change the filter and saw fairly large chunks of metal stuck to the magnet. Part of a bearing assembly. At that point I pulled the BTS trans out of my other truck and put it in this one. Since this one is my work truck and at times gets driven out of state, 100% reliability was important. The other truck was already lined up for a ZF6 swap anyway. If you are thinking about getting one, do it. Just make sure it isn't a sacked out POS. Check the blowby. Look at the air intake tube between the filter and turbo and make sure it's clean. Jump the stater solenoid on the fender with the key off and listen to make sure it spins over evenly. If you do buy one, if it has an auto trans, just set aside the money for a rebuild and expect to spend it at some point. Also keep a spare OEM cam sensor in the glove box, and a 10mm socket to change it, should the need arise. There's more advice I could give, but I've already typed a short story 😆

Radiator will be fine. If it's like that for a long time I'm sure the oil could possibly degrade the plastic, but I wouldn't worry about it. I did have to replace the radiator in this truck several months after doing this job, but I doubt it had anything to do with this problem and had everything to do with it being over 20 years old and going through countless numbers of heat cycles over the course of around 500k miles. The plastic split right at the upper hose attachment. I did have the upper hose blow out on me though, and I do contribute that to the oil in the coolant, the rubber was really soft. I would recommend replacing the upper and lower main hoses if you have this problem, but I wouldn't be concerned about any of the others. I'll be honest, I never did flush the system. All I did was use my vacuum brake bleeder to pull off the layer of goo that accumulated at the top of the reservoir every once in a while until no more was visible. Truck is still running fine.

Yeah I would say it's just the orings. It's pretty common on these trucks as they age. You usually notice it in the winter on cold starts, then it stops leaking after running a few minutes. Obviously it can happen in warmer months as well though. If there is no suspicions of oil and coolant mixing, and the gasket mating surfaces are in good shape, I'd say just reseal it and run it.

Thank you so much for the reply back. I will go into the job myself with that in mind now.@@darkhorseautoanddiesel

@@rubenguerrajr5833 You're welcome. Helping people is the main reason I started making these videos. It is not a fun job by any means, and it can get very messy, but you'll save a lot of money doing it yourself versus taking it to a shop.

Yes it did. I've put somewhere around 50k miles on it since I made this video and all is still well.

You mentioned head gaskets as well how do I test them to make sure they are leaking?

The trick to keeping coolant out of the oil is to vent the cooling system pressure after you shut the engine down. When the engine is running, the oil pressure is higher than the coolant pressure (unless you have an oil pressure problem), allowing oil into the coolant. Once you shut the engine down, obviously your oil pressure drops to 0, but the cooling system slowly drops from around 16 psi as it cools, which can take some time, allowing coolant in the oil. As long as its not a horrible leak, you should be ok to get by with that to at least get you home. Just remember to tighten the coolant cap before you start it, and unscrew it every time you shut it down. Chances are, you have coolant in your oil, just not enough for you to see it. I only knew about mine from an oil analysis. How long you can get away with that? Well, I'd recommend fixing it ASAP and driving as little as possible until it's fixed. For me, since this is my work truck and my primary source of income, and was very busy with work at the time, I did this for about 6 months, and was driving a 9 hour, 520 mile round trip every other day for about 3 of them 🤣 I would NOT recommend anyone else do the same. I took my chances with the hope that it wouldn't turn catastrophic. I got lucky.

@@darkhorseautoanddiesel ok thanks man think you saved my vacation.. I’ve been stressing and not able to just enjoy myself 👍🏻🇺🇸👍🏻

@@hondaxl250k0 You're welcome. Granted, I can't guarantee that this will work well for you, but based on my experience and knowledge, you should be fine. Enjoy your vacation!

I didn't need to. I let it drip out for several days, and the little bit that was left in the system floats to the top of the reservoir, so I'd use a suction gun and draw it off when there was enough to justify the minimal effort. After a few months there was nothing left to draw off. I haven't seen a trace of oil in the reservoir in many months.

While that technically *could* happen, it'd be very hard to do and therefore extremely unlikely. I've never seen it happen. Typically a bad cup results in fuel in the coolant. In my case it was definitely the oil cooler.

So if u just have a slight oil ring in your coolant reservoir do u think it's just the oil cooler?

@@derrekallen2089 I can't answer that with certainty, but I will say, probably. On a relatively stock engines, 7.3s have a VERY low rate of head gasket failure. While it's not impossible, it's not likely. Not that it's an easy 5 minute job, but it's significantly easier to reseal or replace the oil cooler than it is to replace head gaskets, and given that, I'd reseal or replace the oil cooler first and see if it fixes it. Ideally one would check the coolant system for combustion gasses with the proper tools first, then go from there, but in some areas those can be difficult to find, and considering the age of these trucks, if the oil cooler has never been off before it's probably about to need resealed anyway.

You mean the oil cooler? I didn't clean it, I bought a new one because mine was leaking internally. If I am reusing one, I just use brake cleaner to clean up the sealing areas. I don't clean anywhere else, there's no point unless you plan on painting the outside, then clean that. I'll drain them out but that's it as far as cleaning the inside.

@@darkhorseautoanddiesel Thank you

​@@rubenguerrajr5833You're welcome

You'll get a new one when you order and gaskets should come with it

​@@darkhorseautoanddieselthanks every winter I get the drips which makes a mess under the truck so I broke down and ordered my set I'm glad to find your video that helps me out wondered about draining all the oil just changed it might wait till next oil change. But I don't want the muck you had better go ahead and just do it thx again

The brass plug on the filter side end cap? Oh man... the whole engine is a write off now.... Just kidding. Just snug it back and and run it. The worst thing that could happen is that it seeps a little oil, but that's HIGHLY unlikely. Even if it did, it's a 7.3, you wouldn't notice it amongst the other leaks and grease all over it haha. If it makes you feel better you could pull it all the way out, put some new thread sealer on it, then reinstall it, but you'd probably just be wasting your time.

@@darkhorseautoanddiesel does it need to be a certain amount of turns or something special

@@MrJared0099 Just pretty snug is good. There is torque specs for NPT fittings, I just don't recall what it is. Should be 1/8" NPT I think. Don't put the hulk on it because NPT threads are tapered which could split the aluminum housing, but tight enough it won't leak. I just go by feel, then say, "that's not gonna leak." The last step is important.

@@darkhorseautoanddiesel just a question a mechanic told me that adjusts oil pressure is that true

@@MrJared0099 We're still talking about the brass plug on the outside of the oil cooler end cap right? I mean, it CAN adjust oil pressure, in that, if you completely remove it, the oil pressure IN the engine will have a reduction because a great deal of it will be rerouted to OUTSIDE of the engine in the form of a horizontal geyser until the cank case empties, at which point you will have zero oil pressure, but then the engine will shut down because the injectors use oil to fire. Please don't ever take anything to that "mechanic" ever again.

About 2 weeks and 3 days. To be fair, I had to wait about 2 weeks for the new oil cooler to come in, and I didn't work in a manner than anyone in their right might would consider urgent. If one needed it done quickly, as long as you have all the parts and materials on hand, I would say that even with very little experience a person could have this job done in under 4 hours pretty easily.

Thank you for all your help

Not really. You can if it makes you feel better but if there's no signs of mixing I wouldn't go out of my way to do it. If you happen to have the stuff laying around in the shop it wouldn't be a bad idea just for piece of mind, but the OEM ones rarely leak internally. This was the first one I've personally seen leak internally, and it was aftermarket. You're welcome. Helping people is the main reason I started this channel.

I had to watch the video to see what you were talking about. I now see what you mean. It's not cracked though, not sure why it looked like that in the video. Still running the same trans over a year later.

Help has arrived. Unfortunately, the help isn't sure what the problem is.

@@darkhorseautoanddiesel 7.3 oil cooler, I have removed the old one and cleaned the surfaces, there is pitting in the metal on the block side and filter head/ manifold. Not sure if I should run it or do something about it

​@@Bmxr1991depends on how bad the pitting is. Mine was pitted, as you may have seen in the video, I put some silicone in the pitted area and still running it to this day. If it's not horrible, you can probably do the same.

@@darkhorseautoanddiesel so maybe just add a thin layer of etc to each side?

@@Bmxr1991 A very thin layer, yes. Like, just enough to cover the surface. That's also assuming the pitting isn't horrible. Without actually seeing it I can't say for sure if it's gonna work for you. If it's similar to what mine was in the video you should be fine, I'm still running mine with no issues.

No, unless there is so much in there that the rest of the engine is likely trashed too.

In our case the cooler failed causing the oil and coolant to mix

I've heard of people putting dishwasher detergent in the cooling system to clean oil out of it, but it can be quite corrosive, so you have to be careful with it. In my case here, this is my own truck, so I never actually flushed the system. The oil left in the system will always work its way to the top, so it collects in the reservoir where you can use a suction pump to draw it off every now and then, which is what I did. If it was a customer vehicle I would have flushed it.

Replace coolant with simple green /water. Or get some motorcraft VC9 ($50 quart)