So this christmas my wife and I were going to make a road trip from San Diego, CA to a little in east Texas. When we pulled over in Gila Bend for gas i noticed that the temp. gauge had started to climb. It wasn't overheating but it was surely on its way. When i opened the door i noticed that dreaded coolant smell, and when i checked the radiator, the coolant was WAY low. So we get towed back to california, and this past weekend i finally got a chance to pull the head that was leaking. It ended up having a crack between the valves on my number 6 cylinder. But thats not the point of this thread. The point is when i pulled the heads i still noticed a fairly evident crosshatch pattern on all cylinders on the left bank. And the ridge at the top of the cylinders is negligable, i mean its there, but its very small. A couple months ago i did a vacuum test with a steady 20 inches and passed a compression test with flying colors. Is it really common for these engines to show such little wear? I understand that with underdrive transmissions engine wear went down alot but wow, i'm really surprised. I'll try to post some pictures tomorrow when i get home from work.

 

I just put head gaskets on my 96 Explorer 4.0 OHV V6. Valve covers were clean enough to eat out of. NO carbon build up on/around valve stems. Next to no cyl. ridge...still traces of cross-hatch....no gunk in intake ports
Guy I bought it from had it 5 years and put about 120K on it...heads never off. I got it at 185K, now has 220K. He used nothing but Kendall, I'm a Quaker State guy.
I wrenched in a Chevrolet dealership years ago and opened engines with less miles and saw everything from clean to black cottage cheese. This is only the 2nd Ford product I've ever owned and would recommend same vehicle/engine to anyone who asks. Great little truck and a very dependable motor (until it gets hot and blows head gasket....)

 

My 1996 Explorer V6 4.0 has around that same 220K and it is going in to have the heads dealt with next Monday as the number 4 cyl is taking antifreeze. Still been driving it to work 15 miles and as long as I keep it plugged in at night and warm up engine it runs decent. It will be interesting to see how clean it is as I run Mobil. Hope this pays out putting more money into it, or at least another 100K.

 

Yes, the now discontinued OHV 4.0 has a record of going the distance. Not so the SOHC model. Thankfully, the current SOHC is improved, but models from '97 to '04 or so will never see 220,000 miles without serious work.

 

Thanks for that peace of mind (not). I am in the process of buying a 2002 Explorer Limited with that engine in it. It has 135k on it now. I drive 120 miles a day so the mileage will add up quick. As an example I have a 2006 KIA Spectra and when I started this job in October of 2008 my car had an even 14,000 miles on it. I stopped driving it at 14,000 even just cause I didn't want to rack up the miles. So now that Ive been using it for work 365 days a year and some personal driving I now have 111,000 miles on it. Not even but close enough. Between Oct 2008 and Jan 2011 I have put over 90k miles on my car. What do you mean serious work? timing kit, plugs and wires, constant oil changes, fuel filters, air filters, sea foam. Anything more serious than that?

 

Serious work = rebuild.

To service the rear cam chain tensioner, you have to remove the engine. And you will probably have some bent valves if it lets go before you get to it.

I'm not sure what year they changed the cam chains to all up front, but I would be very wary of buying the old set up.

This is pretty low miles, but here's an example:

https://www.ford-trucks.com/forums/1025830-uh-oh.html

 

I don't think I would call pulling an engine and replacing bent valves a rebuild. I can pull it no problem. So you are saying I should just pull the engine and put all 3 chains on when I buy it? Is it possible to swap in the V8 engine? I don't mind doing work on it. Its everything I want - the engine.

 

All SOHC engine have a chain in the back regardless of year. The newer ones are improved and I have seen a few with over 200k. Back to the OP, you can prob get a set of reman heads from eBay and put another 220k on that engine. There are several stores on there that have warranties and quality parts. I have bought a few sets from there.

 

My 99 with 4.0 ohv only has 161,000 trble free miles. Didn't trade it in when we bought used 07 Edge. One issue with the O rings on upper intake and fixed myself. Was causing lean burn trouble code L and R bank.

 

Seems I got some bad info on the chains. I did go on Napa web site and find only one set of timing kits from '98 to '06--seems there are several variations. Do you know what Ford made a change or fix?

As far as calling this a rebuild, well it clearly isn't a complete rebuild, just a top end, but is it not true you have to pull the engine to service the back chain, because of access needed under the bell housing?

IF the chain were to let go at speed, I would think you could have piston damage or worse as well.

I hate to push the resale down further, since I own a '98, but anyone buying one of these deserves to know the potential for a high dollar repair. Since the OHV had a good record of over 200k, it would stand to reason that with a proper tensioner set up, the SOHC version would do the same. The question is, what year did Ford do the fix?

 

I had a 93 Ex ohv 4.0 with 160,000 miles on it but I traded it for a 76 F100 4x4 on 33s. I think I am going to wait until I find a white or black V8 Limited with the dark gray interior.

 

That cross hatch can be a bad thing. Most of that should wear down in the break in period. The fact that yours is still there says this engine was never broken in properly and is not getting a full ring seal. It may still hold compression fine, but it will have more blowby than it should and it will get worse over time. All the crosshatch area should be at least slightly polished, which indicates the rings are making full contact.

 

Well thats not to say that the cylinders didn't have a good worn polished look to them, I was just making a point that for 220,000 miles i was surprised that you can still see the cross hatching and that the ridge at the top of the cylinder is barely noticable. Just one more reason why i am loyal to Ford products.

 

Ford's motors are for the most part very well made.

 

I don't think anyone disagrees with the fact that Ford engines are well made but I do not believe they are all well designed. Plastic manifolds, two part spark plugs, aluminum heads without steel inserts for the plugs to screw into, and having to remove an engine to replace the timing chain were ideas that should have stayed on the drawing boards.