Completed Project Kirby's 1991 Ranger Build Up

[410Fortune]

I just mean the crank to the cam at the chain and tensioner.. something causing low compression! Valve cover would have to come off… unless that
Rebuilt Motorcraft you got just wasn’t good?
Head gasket or rings or valves?

 

[Kirby N.]

Oh I understand. She needs to come apart. I guess I have a thanksgiving project

 

[Kirby N.]

The hunting trip went fantastic. The didn’t get to take the Ranger but I got to ride shotgun in my buddies raptor.

I killed 2 elk and the freezer is full.

So got back, had some turkey and today the Ranger got my attention.

First up, leak down test. I tested cylinder number 4 because it was easy. I lined up the tdc mark. When I did pressurized the cylinder I could feel air in the exhaust and the intake. So I turned it 1 full turn just in case it was 180 off. Same results. So I turned the crank one more turn. Same results.

So off with the upper intake and valve cover. Then I took off the rockers just in case I didn’t have the valves closed. Pulled all the pushrods. Tested again. Same results. I could feel air coming out of the intake and out of the exhaust.

Off with the heads!

I tried calling machine shop that did my valves- they obviously screwed something up big time- and I think they are out of business. That’s handy. They were in the biz since the 60s at least. My dad used them the first time late 60s. I had some issues with them when they first did the head and had to take them back. Perhaps they sucked themselves out of business.

So I don’t have a ton of options:

I might be able to get some 95tm heads from a national place, but it seems like it was 93tm or 98tm. The 95s have the right exhaust ports and right volume.

Anyone have experience with Odessa or King or Clear water heads?

Anyone know a good machine shop in Denver area? @410Fortune @Brett?

 

[Paul]

That's a thumb's up ^ ^ ^ on the Elk, sorry about the heads and machine shop woes. . .

 

[Kirby N.]

Thanks Paul!

Here is a picture of the heads before they went into the ranger (from an old post in this thread)

And when I pulled them from the junk yard:

It seems to me that the seats are much more seated- the valves are way more recessed now. I bet that machine shop screwed them up.

 

[410Fortune]

Blue Oval Performance Engineering, 3761 S Kalamath St, Englewood, CO 80110, US - MapQuest

Get more information for Blue Oval Performance Engineering in Englewood, CO. See reviews, map, get the address, and find directions.

www.mapquest.com

I would
Compress the springs on 4 and pull those valves have a look at the valve seat

How to cylinders and pistons look?

 

[Kirby N.]

The cylinders look pristine! I need a compressor to get the valves apart. I’ll see if I can find a friend with one. Thanks for the recommendation on the machine shop.

 

[410Fortune]

There are several good machine shops in Denver south federal has a good one I can’t remember the name of right now

 

[Kirby N.]

Well, I figured out that another machine shop bought the place out that did my heads. And some of the guys work there now.

I took them in and the guy said the exhaust valves wore out the seats and that he sees it all the time on a 4.0. And that I shouldn't be running a later head and block with an early computer. And that I must have put a heavy load on it or ran propane or got it hot.

I told him all that was crap. That it hasn't gotten hot, has had 30k miles on it, and that they must have used garbage parts because I have had plenty of 4.0s go 300k without this garbage. And all of the valves did the same thing- so it has to be shoddy work.

The tech took an exhaust valve off and showed me how it had "extreme wear" on the seat. Said he would talk to the boss and let me know what they would do- fix it for free or what.

We will see. I would really like the money back that I gave them more than anything.

 

[Kirby N.]

Well I heard back from the machine shop and they are not going to do any sort of warranty for me. They said there is some sort of service bulletin about using later heads with an earlier Computer and causing a lean condition . However, I don’t think that is exactly what the tsb says. And they didn’t realize that the intake valves are garbage too which isn’t a lean issue.

does anyone know what tsb they are referring to?

 

[410Fortune]

Let do some research about using 95tm heads on early blocks

I have never had any issues doing so
And I am not alone

“At the bottom notice the post that talks about the fast burn chambers actually being LESS prone to detonation. 95TM/98TM heads are the same in the combustion chamber area, the main difference between them being that the 98TM exhaust ports are smaller. That being the case, unless you port those 98TMs....95TM heads are much mo' bettah.”

Another 4.0L OHV Build Thread (with 95TM heads)

Another 4.0L OHV Build Thread (with 95TM heads) Now with a Video!!! A couple months ago I picked up a '94 Sport 2-wheel drive for a very reasonable price with some motor problems (previous owner is a ExplorerForum member). My original intention was to swap a V8 drivetrain from a mid-90's model...

www.explorerforum.com

More

4.0L OHV head compatability?

I'm looking to pick up a set of heads to replace the ones on my 94 4.0. My question is what head cast numbers would fit and run good? Which head could possibly bump compression up a little? Sent from my SM-G900R4 using Tapatalk

www.therangerstation.com

At your
Altitude I really doubt there is enough oxygen and compression to be worried a out the slight bump
I’m Compression from the 95-98tm heads
The factory pcm can compensate and I don’t remember you complaining about pinging…
There are tons of cheap 4.0 Heads out there
These engines can and should be able to take some abuse

We Even ran 85 Octane in our turbo cars (they sell 85 in Colorado because you can get away with it at elevation) buying 91-93 octane is a waste of $$$ when you live/ commute at 6000-11000 ft in elevation

Now this doesn’t mean that 30k miles of a possible lean condition didn’t lead to premature wear, it very well could have
But it’s not because your choice of 4.0
Heads

Read:

Google Search

www.google.com

 

[Kirby N.]

I learned a few things today and I picked up my heads. The machine shop was calling this a TSB- its not:

I believe it is just a post off of the ranger station:

I have read this over and over. Its a little wordy. 1995-96 Aerostars ran 93tm heads and Deep dish pistons and the early computer calibration. So my setup with 91 computer shouldn't be ran with the 95 style pistons and 95 style head because it will burn down?

I have no idea the source or the "ford engineer". So that doesn't really help. I am told lots of guys are running this setup with no problem- so I don't know why this would hold more weight than that.

So I called every machine shop that was recommended here and on other sites to get some other opinions and most recommendations were either out of business or didn't want to take on the work even in Denver. Blue oval performance is no more.

I did however take it to another machine shop in my town, and I actually got some answers! The machinist has been working in this industry for 40 years. He looked them over and said it was pretty common. He said sometimes the heat treat on the head doesn't do a good job of hardening and this can happen. When I explained it had new seats put in by another shop he wanted to see the receipt. When I showed him, he immediately said he knew the problem. Apparently SBI used to make a good seat made in USA. A few years ago they started being made in China. And now they suck. The guy said he had a couple do this before switching away from SBI. He said they dont even machine well.

When I told them they were loud and I took them back and the other shop said they pressure tested fine, but then hand ground the valve seats again- he said why would they need to do that if they pressure tested fine?

So I think this guy knew his stuff and was being straight with me. He said that was why both the intake and exhaust valves took a dump- because the seats are garbage.

He made a phone call and he can get me some repop 95tm heads and put these springs and valves in them- but he didn't know if my valves would be any good.

However, I may have a line on a set of 95TM new old stock heads, so I am going to see how those pan out. They will be here by the end of the week.

 

[410Fortune]

What a fiasco

This is the world we live in now, substandard parts
Seems like you may have found the right person to rehab your heads!

Again at your elevation there is no way the tune is causing detonation and premature wear of the pistons and heads
I ran 91-94 computer with 95+ engine many many times never an issue
4.0 ohv is tough as nails should be able to handle some serious abuse… when it’s put together correctly the first time around

 

[Kirby N.]

I agree with that. Figured out the source of these words- it’s an article from engine builders magazine here:

Ford 4.0L V6 Engine

Exploring the Ford 4.0L Engine: Evolution, Components, and Rebuilding Tips for Rangers, Explorers, and Aerostars. Learn more here!

www.enginebuildermag.com

And I think it is more about using the late heads in an earlier block and unknowingly bumping the compression- more than anything.

I did find a good source to fix my heads, however, I got a package from eBay yesterday:

New old stock motorcraft heads loaded with valves. I don’t think I can do any better than these for quality parts! I think I am going to run them. The last nos heads I got came in a ford box. I wish these did, but they look every bit the part.

eBay has bestowed a blessing. Ha. I don’t even think they need to be inspected, although my dad did suggest I take them to the machine shop and have him test them. Do you guys think that’s necessary?

 

[donalds]

I'd just install them

 

[Brian1]

What seller did you get them from? I've been eyeing some from Bishop Engine on ebay but haven't pulled the trigger yet. If you don't see anything that could be an obvious problem I would just install and run them.

 

[Kirby N.]

Allied motor parts in Atlanta georgia.

 

[410Fortune]

What color are the valve seals? (Inside the springs)
The good felpro over the counter valve seals are blue
Since these are new old stock and not remans, they should be ready to rock n roll

 

[Kirby N.]

Going back together. I am going to get a baseline for compression before I fire it. I need to prime I anyway. Probably button it up on Monday.

close up of the old heads compared to the new one:

Way less recessed. I don’t think the new ones don’t have seats, but you can see where the area around the valves is heat treated. The machine shop also guy said they use induction to heat treat them.


The springs and seals look new.
The seals are green @410Fortune

I decided not to use rock auto for the gaskets because I hate when they send the wrong stuff or jacked up stuff. AutoZone was having a Black Friday sale so I got victor reinz or Dana gaskets.

good thing too. They were boxed up but had 2 different gaskets. So annoying.




This was the gasket that was different I didn’t like that it didn’t have steel around the cylinders. It may have had it under the gasket material- but it was frustrating that it was different. So I returned it to the local hub autozone and got a felpro set. It came with cork valve cover gaskets so I bought another set of valve cover gaskets separate

 

[Turdle]

Good call. I just discovered a bad cork on a 30 year old bottle of cognac. Can't let it leak out so ..