How bad is the HG job on a 7.3 IDI?

[steelholder]

I finally have enough room to do this job. F250 1992 7.3IDI non turbo 143k, I have never done a HG job but have done simpler things like suspension work, swap starters, pulleys,timing belts, replace valve cover gaskets, suspension/brakes, engine/trans swaps etc. The best quote I can get in my area for this job (including the seals and any other preventative work that is easier with the engine out) is around $6k. It's steep, def more than I paid for the truck. I have already tried retorquing the head bolts with no luck.

***SYMPTOMS*** - Almost absent, the only reason I know I have a HG leak is because I can see it bubbling out near the head, close to where the oil filter is located (please see clip). I am positive there is a leak there and its not just something that is leaking from above and boiling at that point. I am not overheating, no water in oil etc etc.

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I want to make this truck nice, fix mechanical issue and get it a nice paint job, keep it stock, maybe a slight leveling front lift, keep it for the rest of my life and take it fishing or cruising around on the weekend (maybe that's my answer right there). I have a few questions and concerns.


1. I have heard I need a valve job for job like this but have no idea how or what that is, never done one. Can this be something that can be learned or leave it to the pros?
2. Besides pulling the engine and checking for uneven surface of head, sending to machine shop if so, and adding a new HG what else is there? I'm a big youtube learner and the lack of videos is a concern, I don't have a buddy that knows how to work on these unfortunately
3. Just concerned I will pull engine split it and be overwhelmed I guess.
4. Dumb question alert - what if i just add some high temp epoxy to that are to keep that leak from leaking?

I think this may have happened after using seafoam. I'm not positive but I suspect it may have cleaned out whatever buildup was keeping that leak tight, not sure it matters as it's there now. What do you guys think?

 

[Nero]

If it is the stock head gaskets, they are stamped steel, and will do this over time.

Some swear to just retorque the head bolts and see if it goes away on its own. If you aren't losing coolant and it is just combustion getting past, may be worth a shot.

As for just doing a head gasket, it is pretty straightforward. You do not need to do a valve job or send it to a machine shop. Just get a straight edge and check for head flatness and deck flatness.

For the heads themselves, some cracking near the injection cups is normal, so long as the cracks do not extend past the firing ring. Cracks between valves is a big no go.

Now is a good time to put studs in, even if you are currently N/A, they are cheap insurance. Plus I bet some of your head bolts will have damage.

There are 3 major gaskets you'll need, head gasket, exhaust manifold, and valley pan. If your valley pan isn't rusted, you can just silicone it back on, as replacements have gotten a little pricey as time has gone by.

Oh and don't take the injection pump gear housing off.

Do your best not to damage the locating dowels, they usually stay in the block, but sometimes come out with the head. They aren't made anymore. If you need some, Justin at R&D custom makes them.

When you pop the heads off, residual coolant will flow into the cylinders. Be sure to towel that up as best you can.

 

[steelholder]

If it is the stock head gaskets, they are stamped steel, and will do this over time.

Some swear to just retorque the head bolts and see if it goes away on its own. If you aren't losing coolant and it is just combustion getting past, may be worth a shot.

Tried this already with no luck unfortunately, there is leakage not sure what it is, comes out black by the time it hits the floor.

As for just doing a head gasket, it is pretty straightforward. You do not need to do a valve job or send it to a machine shop. Just get a straight edge and check for head flatness and deck flatness.

What if the heads aren't flat? Any idea what a machine shop charges for cutting these?

For the heads themselves, some cracking near the injection cups is normal, so long as the cracks do not extend past the firing ring. Cracks between valves is a big no go.

Kinda concerned it may be busted in there, same question here, if it does need a valve job, how hard is that?

Now is a good time to put studs in, even if you are currently N/A, they are cheap insurance. Plus I bet some of your head bolts will have damage.

Any specific brand?

There are 3 major gaskets you'll need, head gasket, exhaust manifold, and valley pan. If your valley pan isn't rusted, you can just silicone it back on, as replacements have gotten a little pricey as time has gone by.

I keep hearing that I should replace seals with the engine out. I don't know this engine well, what specific seals and other maintenance work is typically done while engine is out?

Oh and don't take the injection pump gear housing off.

Do your best not to damage the locating dowels, they usually stay in the block, but sometimes come out with the head. They aren't made anymore. If you need some, Justin at R&D custom makes them.

When you pop the heads off, residual coolant will flow into the cylinders. Be sure to towel that up as best you can.

 

[Nero]

If you are pulling an engine, doing the pan and front/rear main seal are always advised.

Head studs, I have a set of ARPs in my engine. They are no longer made.
Justin sells a set of custom made ones, and CDD resells Gator brand ones. I just installed a set od Gator ones and used Justin's torque method of 150ftlbs, so far so good, but the engine is still on a stand.

If your heads aren't flat, I would suggest finding a local machine shop to machine them. Most shops won't touch them since they have the precombustion inserts and they are very hard. But take it with a grain of salt, I found a turbo idi engine with 320k and the heads had no cracks. Had an unknown mileage N/A IDI and there were cracks between valves, so it really is luck of the draw.

As for valves, I got all new Mahle valves from rockauto, and had a friend lap them for me.

 

[steelholder]

Thanks Nero, I guess I'm in between just paying someone to do all of that work or potential work or trying it myself. $5-6k is steep but I think that would guarantee it's done correctly versus a steep learning curve by doing it myself and potentially messing that up. If I do the work myself I may still need to fork out thousands on cutting or valve job if needed..hmm.. anyone else done this that can give some words of motivation?

What is the process of pulling the engine? Just unplug things and pull or easier by dropping the trans etc?

 

[Nero]

Puling the engine... Pretty much yeah.

You don't have to have the valve seats cut, just lap them. Something you can do, lots of youtube vids out there on how to. Definitely very time consuming and your hands will cramp a little

 

[steelholder]

Puling the engine... Pretty much yeah.

You don't have to have the valve seats cut, just lap them. Something you can do, lots of youtube vids out there on how to. Definitely very time consuming and your hands will cramp a little

So just pull it from top with a hoist, no need to drop anything before?

 

[ROCK HARVEY]

I did my head gaskets a little over a year ago. I didn’t pull the engine, I just used a cherry picker with a load leveler to lift and position the heads. I did call a friend to help with the install; he worked the jack on the cherry picker while I guided the heads into position. It was tight getting to some of the rear head bolts, but I would do it the same way if I had to do another one.

I had similar concerns to you about opening it up and finding out I need new heads. I didn’t want a lot of truck downtime, so I bought a used engine off of Facebook marketplace beforehand and prepped those heads to swap onto my truck. You’ll want to check for flatness, cracks, and valve guide wear.

I recommend replacing the seals in the oil cooler while you have the heads off and have easy access.

There were a couple good videos on YouTube that helped me out. I also have the service manual and can post pictures of the instructions if you want. As for head bolts vs. studs, I believe Justin from R&D did some failure testing on different fasteners years ago and based on those numbers I felt confident just buying new head bolts. Both the bolts and head gasket kits are often on sale on rockauto. Good luck and keep us updated!

 

[steelholder]

I did my head gaskets a little over a year ago. I didn’t pull the engine, I just used a cherry picker with a load leveler to lift and position the heads. I did call a friend to help with the install; he worked the jack on the cherry picker while I guided the heads into position. It was tight getting to some of the rear head bolts, but I would do it the same way if I had to do another one.

I had similar concerns to you about opening it up and finding out I need new heads. I didn’t want a lot of truck downtime, so I bought a used engine off of Facebook marketplace beforehand and prepped those heads to swap onto my truck. You’ll want to check for flatness, cracks, and valve guide wear.

I recommend replacing the seals in the oil cooler while you have the heads off and have easy access.

There were a couple good videos on YouTube that helped me out. I also have the service manual and can post pictures of the instructions if you want. As for head bolts vs. studs, I believe Justin from R&D did some failure testing on different fasteners years ago and based on those numbers I felt confident just buying new head bolts. Both the bolts and head gasket kits are often on sale on rockauto. Good luck and keep us updated!

Thanks, please post the video links and resources you used. Did pulling just the head allow you to replace the front and main seal? Or does the whole engine need to be pulled for that?

 

[Nero]

Thatis a good way to do it too.

When I built my engine I did it in chassis as well. I left the exhaust attached to the heads and pulled it as one chunk. You can pull the manifold bolts through the fender liner too if you wish.

Front seal can be done in chassis, rear can as well if you pull the transmission.

 

[steelholder]

Thatis a good way to do it too.

When I built my engine I did it in chassis as well. I left the exhaust attached to the heads and pulled it as one chunk. You can pull the manifold bolts through the fender liner too if you wish.

Front seal can be done in chassis, rear can as well if you pull the transmission.

Seems like that rear seal would be an absolute pain. How bad is it to drop the trans without the truck on a lift?

 

[IDIBRONCO]

Generally not very difficult.

 

[steelholder]

Generally not very difficult.

Ok but the transmission needs to be dropped right? If so sounds hard working on your back.

 

[IDIBRONCO]

It should be, yes. It may be possible to slide the transmission back far enough to not have to drop it completely out. Depending on your truck's set up and your flexibility, you might not have to lay on your back to work on the rear seal.
Honestly, with all of the work that you're talking about doing, I think it would be easier to pull the engine out so you can have easy access to everything while it's on a stand.

 

[Nero]

Ok but the transmission needs to be dropped right? If so sounds hard working on your back.

Correct, transmission needs dropped to do the rear main seal. If it isn't leaking... Leave it alone is my philosiphy. I have had my transmission down twice and my engine out once... Original rear seal from 1988 doing just fine.