How likely to have new heads cracked?

[WilliamWallaceGS]

UPDATE: 8/8/13
For anyone who doesn't care to read everything, one of my heads in fact came back with a crack. One machine shop did not catch it, and the current machine shop missed it the first time. I had to ask again for them to look at the oil port during the test, because it was overlooked. One of my heads passed fine, even up to around 50 psi. The other one started bubbling around 20-30 psi. So there you have it, if you ever have anyone pressure test these heads, you have to point out that oil port specifically, since it seems like an easily overlooked area.

Hello everyone,

I recently had a thread open about some noisy lifters I had gotten during my engine rebuild. You can read the thread here: http://www.explorerforum.com/forums/showthread.php?t=369534

Here are the stats if you don't feel like glancing at my other thread:
Rebuild 1994 4.0 shortblock, melling HV oil pump, 410 cam, 95 TM heads

During all of that troubleshooting, I noticed I was getting oil in my radiator. I thought I might have screwed up some gasket installation, so I was VERY careful the second go around after replacing my lifters again to make sure everything was perfect.

So I still have oil in my coolant, not a whole lot, but it'll accumulate a nice brown film after about 2 days of driving. Did a compression test, got 215-220 PSI on all 6 cylinders. Checked the plugs and all, no signs of burning coolant, everything inside of the CC looks great. Did a cooling system pressure test, and the system will slowly depressurize with no external leaks. I cracked my drain plug after the pressure test, and sure enough there were water droplets down there. It's not enough water to turn the oil into a nasty chocolate milkshake, my water level doesn't decrease by much, whatever leak I have is pretty small, but who knows when it could get worse.

I put an oil separator in line with my PCV to intake manifold after the rebuild, and that thing has been nasty ever since the rebuild. The inside of that thing looks nasty as crap, because the moisture from the coolant in the oil is getting caught by my separator and mixing with the oil vapors and creating a chunky brown mess.

So after all of that info, here's my question. How likely is it that I have a cracked head right out of the box? I put brand new Engine Quest 95TM heads on, and had a machine shop do a valve job and all. I'm not sure if they did a pressure test or magnaflux though since they were brand new castings. I know there's a thread around here where someone had the same thing happen with his EQ heads, but I think that was a few years ago. I'm pretty sure the block is good, I'd assume the machine shop would test that too (didn't specifically address this), but even if they didn't, before I did the rebuild my cooling system was clean as could be, so the block shouldn't be a problem.

This is a complete bummer. I thought I was out of the woods after I solved my lifter issue, now it looks like she's coming back a part. I've got a pretty hectic work schedule for the next month, so now I have to figure out when I'm going to tear back into this thing.

 

[wood1]

Crap that sucks man. It's not rocket science, pretty unlikely that you have a gasket issue, you no doubt know how to rebuild an engine... I'd call the head manufacturer and see what they have to say about it. I guess in the end you are going to have to pull the heads again and have them checked. New head bolts every time?

 

[Anime]

How likely is irrelevant, if it's a cracked head it's a cracked head.

I'd definitely call EQ or the seller you bought them from and see what they'll do for you. Hopefully they'll send out replacements and return labels to have the old ones shipped back, so you can swap them out rather than have to return the old ones and wait for new ones back.

 

[malohnes]

These heads are a pain sometimes. My heads where repaired, both of them by a very highly regarded machine shop and they lasted 3 years trouble free. Now, after 1 year, they are seriously leaking oil and coolant. I say after on year because prior to that, the only sign of troubles was occasional water temp drifting. One would expect new heads to be fine, yet sometimes not. Once you get it all sorted out all will be right and you'll be happy.

I hear and feel your pain tearing into your engine so much chasing gremlins. I'm in the middle of putting on new 95tm heads myself. I was betting on bad head gaskets and lost since I'm still having troubles. I also discovered that the thermostat tube is striped in the bottom hole and I rethreading ain't going so well. Sometimes life is a drag.

By the way, I got my heads via King Cylinder Heads. New, assembled and so far, everything is right on. EQ is a pain to deal with here in Alaska...shipping was more than the heads...not worth it. I paid a bit more, but I get new castings and no hassles and way cheaper shipping than EQ.

 

[WilliamWallaceGS]

I suppose I should have titled this thread "Who else has had "new" heads with cracks" because that's really the info I'm curious about. I'm about 95% sure it's the heads, and 100% sure I'm tearing back into this thing, it's just a matter of when (working six 12s for the next few weeks, so my free time is at an all time minimum).

I was gonna go with Alabama heads at first, but then I read good things about EQ, and I like the fact that they have the larger exhaust ports unlike Alabama's "hybrid" head. I also saw good stuff about King Cylinder Heads too, but I went with EQ since the price was good for the bare heads and I was expecting new castings to be pretty flawless (I installed SI intake valves and OEM exhaust. SI only had 6 intake and 4 exhaust valves available when I ordered them, with no ETA on anymore).

Malohnes what particular area of your heads did the machine shop fix? With my issue, my crack has to be somewhere in the oil passage that feeds the rocker shaft, because that's the only oil port that goes into the heads that's pressurized. It all gravity drains back towards the center of the engine back into the sump. I'm wondering what kind of repair you could even do if you had a crack in the oil passage, you can't drill the ends to stop propagation then seal weld it shut due to space, and I'm not sure what else you could do to fix it.

 

[jd4242]

I suppose I should have titled this thread "Who else has had "new" heads with cracks" because that's really the info I'm curious about. I'm about 95% sure it's the heads, and 100% sure I'm tearing back into this thing, it's just a matter of when (working six 12s for the next few weeks, so my free time is at an all time minimum).

I was gonna go with Alabama heads at first, but then I read good things about EQ, and I like the fact that they have the larger exhaust ports unlike Alabama's "hybrid" head. I also saw good stuff about King Cylinder Heads too, but I went with EQ since the price was good for the bare heads and I was expecting new castings to be pretty flawless (I installed SI intake valves and OEM exhaust. SI only had 6 intake and 4 exhaust valves available when I ordered them, with no ETA on anymore).

Malohnes what particular area of your heads did the machine shop fix? With my issue, my crack has to be somewhere in the oil passage that feeds the rocker shaft, because that's the only oil port that goes into the heads that's pressurized. It all gravity drains back towards the center of the engine back into the sump. I'm wondering what kind of repair you could even do if you had a crack in the oil passage, you can't drill the ends to stop propagation then seal weld it shut due to space, and I'm not sure what else you could do to fix it.

i am the one that had a crack in this exact place on a brand new set.i also didnt test them before i installed them.EQ sent me out a brand new head free.didnt help me out on the cost of gaskets or head bolts tho.not very happy to hear it has happened to someone else tho.i have used their heads many time and never seen another case till nowi am very happy with them and everyone else has been.always have heads checked every time they come off or before they go on,even if they are new.

 

[WilliamWallaceGS]

Stuff happens unfortunately, this was the first time I've had a machine shop do any work like this for me, so I know what to look and ask for next time. I'm just glad I didn't have any porting done before hand, that would have been a huge waste of $$$ if it turns out to be the heads.

 

[malohnes]

William...both heads were welded, driver and passenger sides. The welds were not in the oil passages but in between the second and third cylinder and between the fifth and sixth cylinder on the other head. Transversely welded, left to right, centered between the water jacket ports. The welding job was pretty good visually, however it did not last for more than 10,000 miles. This is not confirmed, since I don't have a machine shop to magnaflux the heads, but that is the sight of an old crack, so it most plausible that that is the problem now.

Some history - My mother owned the truck at the time and let the truck overheat in traffic one time coming home from work one winter day. It dumped coolant all over and oil was in the oil and vice versa. She took it to a high performance shop that had onsite machine shop that was highly regarded. She came home with a BIG bill and a truck that never really ran right since. She was in fact charged for new heads, not to repair broken ones. Mechanical things is not her area of expertise, so she was easily swayed with gear-head talk when she asked questions. I bought the truck from her knowing it wasn't running great.

 

[WilliamWallaceGS]

Bummer, I would hope a weld repair would last longer than that. I haven't done a ton of research on weld repair for heads, but I might consider new heads vice weld repair for reliability. Then again, as some of us have seen, you can't always trust new parts either.

 

[WilliamWallaceGS]

Well everyone, I finally got some time to tear back into the Ranger again and took the heads to a machine shop today to get them pressure tested...

The heads are good, no cracks. My "95% sure it's the heads" comment just got thrown out the window. This is good news, but now my issue is 1) a cracked block or 2) head gasket.

Not that it's impossible, but I seriously doubt it's my block. The block was good prior to any machine work, and unless the shop did something completely out of the ordinary, I wouldn't imagine that the machine shop could crack my block in the process.

I will note that when I took the heads back off, I noticed that my passenger side head bolts were much tighter than my driver side head bolts. They weren't "loose" per say (i.e. finger tight), but I didn't really need to put a lot of force on the cheater bar to pop them loose like I did on the passenger side. I torqued everything to spec, even made marks on the bolts/head to reference about 90 degrees final turn.

So I'm about to go pick up the heads and talk to the shop a bit, I'm not sure what's going on. Maybe somehow I managed to mark my head bolts wrong on one side and didn't tighten them down fully, but my compression readings on all 6 cylinders were good. Maybe it was enough to seal the CC but not the oil port? Who knows.

Anyone know how to test a block with it sitting inside of the truck? I definitely don't want to have to pull that thing out again.

 

[jd4242]

doubt its the block but this is how i tested mine.
http://www.explorerforum.com/forums/showthread.php?p=2258383#post2258383

 

[scdix50]

I have replaced head gaskets on the last 3 V6'S I have owned. I have always gone back thru the head bolts again. Take your torque wrench and add say 10lbs above the setting you used before you started your 1/4 turn of the bolts. Go thru your torque pattern. Add 10 lbs and repeat. (That you are looking for is the lowest and the highest numbers just as the bolts start to move.) That you need is the highest number, set the torque wrench to that number and torque all the bolts the same. Wait a short time-like a soda break, add 2-3 more lbs and re-torque. I tend to use the best FEL-PRO gaskets. I have used the system on other non-Ford engines and have never had to redo a head gasket job.

 

[WilliamWallaceGS]

That's an interesting method JD, I might have to look into something like that. Although, like you, I'm pretty confident the block isn't the issue.

I made sure I did everything to spec the past two times, but apparently I didn't. I just placed an order at rockauto for head gaskets and all. I'm gonna take my time and see if there's anything else I'm missing, and if not I'll try this one more time.

scdix50, I had thought about doing something like that this time. Just snugging them up a little tighter than before, but as many times as people on here have torqued these things according to spec and NOT had any issues, I'm not sure how I'm the odd man out. Any other tips for installing the heads? I mean I did the torque in the 2 increments (with a light coat of oil on the threads and under the bolt head), then the final 90ish degrees, then done.

 

[scdix50]

I had to do a head gasket on a straight 6 in a Jap truck that had been replaced 2 times before. It never need to be changed again. I knew the truck well, it was my late little brothers. His widow and son drove it for many years. I have found, Never torque part way, back off and then retorque as some books. If you only do the 90 degree turn, you will find that no 2 bolts strech the same. You noticed that when you last did the head gaskets. I think most manuals are written for new engines with low miles. I have been turning wrenches on engines since 1967. Do not feal like odd man out. There are untold numbers of guys that have had the same thing happen at least once including myself. At this point, you have nothing to loose and all to get right. Take your time and let the bolts settle after each torque pattern. Think about this a few days, good luck.

 

[scdix50]

Its been awhile, what did you do about the head gasket & head repair?

 

[WilliamWallaceGS]

Well, I ended up experimenting with this, and I think it worked.

I ended up using all new head gaskets (Fel-Pro "Extreme Duty" Head gaskets) and bolts again. Chased/cleaned the block threads, light coat of oil on the bottom of the head bolt head and threads, everything to the T. This time though I did NOT install my lower intake manifold at the same time as the heads (and so far no issues there). After each stage, I waited about 30 minutes before I did the next torque stage. I then rechecked the torque, then moved on to the next round.

Once I got up to the 90 degree turn, I did just that...90 degrees. I then used my torque wrench to try and estimate about what torque most of the bolts were. On my particular application, It was about 106 ft*lbs. I have a clicker type torque wrench, so again, this was a rough estimate. Oddly enough, some of the bolts actually went a few degrees past 90 when I went to 106 ft*lbs, and some didn't move at all. So then I ran it for a while and STILL had some minor leakage. Not nearly as bad as before, but it was there. So I took the valve covers/rockers off and torqued every head bolt to 120 ft*lbs. I got slight movement on them there, but they are all at the same torque now (although not at the same angle). That seems to have done the trick. So far my fluid levels are steady, my oil separator contents look much better, so I'll keep checking it from here on out.

Will my stuff prematurely fail because I didn't follow spec? Only time will tell, but I don't think it'll be an issue. So far everything appears fine. It's interesting how the 90 degree turn does NOT mean that each bolt has the same amount of torque applied, but that works for so many people (except me it seems, dang it). I wonder if my machine shop didn't catch (or even check) my block surfaces for straightness (same for the heads, although they were new castings) and it's off a bit causing this. I don't see why I've had all of these issues, when others do this with no problems.

 

[scdix50]

Thanks for trying my idea. I have always had good luck with doing the extra step. I hope all goes well for you.

 

[malohnes]

Are you making sure you're torquing the heads down while torquing the intake manifold down too? You have to do this to get a good even seal, for both the heads and the intake.

 

[jd4242]

Are you making sure you're torquing the heads down while torquing the intake manifold down too? You have to do this to get a good even seal, for both the heads and the intake.

His last post says he didnt do that this time around.

The head bolts are tty or stretch bolts also so everytime you go back in and try and retightn them you probably will grt a turn or two on them.but thats because they have stretched. You can make them weak and even break the bolts if you do this

 

[WilliamWallaceGS]

I thought about how I went about this for a while before I did anything. Since I wasn't able to get a good seal by following specs, I decided to experiment a little (knowing the risks involved) with my methods. Why I wasn't able to get a good seal following the specs is another issue, one that I'm still not sure of. I'm fully aware that my methods may just be a bandaid that falls off in a few months, and that I may not be addressing the real issue.

I'm still not convinced that not installing the heads/upper intake at the same time will cause any sealing issues. From this logic, anytime you would pull the lower intake manifold to replace the gaskets, you would have to remove the heads too to seal everything at the same time. I wonder if they were installed this way from the factory, I haven't come across info on that before.

As far as the head bolts go, only time will tell if going past 1/4 turn will do any major harm to the bolts or the seal in general. My bolts didn't end up way past 1/4 turn final, maybe 10-15 degrees past that overall. I also thought about whether tightening the bolts some more would just add to the stretch and not so much to the clamping load, but I tried it just to see (again, I knew the risks). So far so good, I did a compression test the other day and still have 210 to 215 psi on each cylinder. We'll see what happens.