It's me again and my endless Head Gasket replacement project. Learning as I go - but not without very valuable help from this forum.
Today I spent 2 hours to go from head off to head on and right back to head off.
One of my biggest challenges was getting the head the top radiator hose and the radiator pieced together as one. I know that my radiator hose which I bought from one of the T parts outfits was too long. It ended up very much compressed at both ends. Is there a trick to this part of the assembly?
So, I finally got everything together, lined up, bolts in place and snugged finger tight. Then, following the proper tightening order, I began to torque them down (45 ft/lbs for my Z head is what I've been told). All went well until bolt #7. Tightened up, apply torque wrench, seems like it's almost there and then boom, loosens. Then snugs then goes to loose. Classic stripped thread symptom. I tried a different bolt in the same hole - same problem. So a sigh of frustration and remove the head - again. Once off, I put a bolt in the #7 hole and it tightened up, torqued to 45 just fine. So now I'm confused.
I suspect that once I put things back together it will be fine, but before I do, I was hoping someone could ease my mind and recommend a reason why this happened.
Thanks in advance
You wouldve been better off to put the head on first and then the radiator. I put the top and bottom hose assemblies on the rad & then install the rad. I've found often you have to shorten the top rad hose some in order for the rad to fit properly for the hood to lay on correctly.
Yep sounds stripped to me...if it isn't the bolt threads then it's the hole. The problem with putting a bolt in without the head is you've got more threads biting than with the head and so it is those few extra biting threads that will hold the torque. Try chasing the threads to see if you can clean them up any...if that doesn't do it...time to heli-coil...it is really the only way to fix the problem and it's fast and easy to do too.
Maybe somebody else will have other ideas...might as well wait and see. But that's what I'd do...heili-coil it.
The water outlet can be unbolted from the head, thus you can assemble the radiator hose and water outlet first, then put the head back and bolt the outlet to the head. Tighten the hose clamps last.
Don't know about the bad thread syndrome, but from your last stripped bolt hole it seems you have some helicoils in the block that isn't in perfect condition?
WOW, you sure are having a time if it... Keep at it. Did you check the length of the bolts like I think somebody suggested? Maybe it's a short bolt? It should be easy to visually inspect the threads. Both should have nice sharp points. Are you tightening up all the bolts in steps not going to 45 at once. Is your torque wrench reading correctly. I'd bolt the head on first then hook up the hose later. You sometimes can feel when it's sitting on the block in it's happy spot and not forced all the way to front or back by the hose. You sure you have the right size bolt? If it's as long as possible without bottoming out and the right diameter and thread pitch then YES you have stripped threads. you already know how to do that so fix it before you proceed. Martin is right unless the bolt is pulling tension you can't tell about the threads just b screwing it in.
Good Luck,,, You need some
Bad run right there friend. I am at an age where I quickly turn to "enough of this" and what I would do is probably what many would not;
Ford realized a better way with the Model A and went to studs instead of bolts. At this point I would take a head bolt to the "bolt store" and buy a set of studs. I would double nut the top of the studs to run them into the block with copper coat or never seize or anything similar and pull them tight with a short wrench and not worry about torque. Remove the double nuts and install the head and torque away...the fine threads on top will let you do that without pulling the threads out of the block as the studs are fully engaged and set, the torque is on top a little at a time. Apparently your block has had bolts ran in many times too tight or not seated or full of junk.
Our late friend Ralph Ricks was blowing a head gasket a year on his Fronty and I told him I put them on with a set of the long Model A water studs...he did that and it was done.
Yes that can make the head difficult to remove in the future but a Model A head comes off and a T head with studs will also. If somebody looks at the motor and tells you it is wrong just poke them in the eye and tell them to look again! It will be fixed, not leak and this problem is over. A nut on top instead of a bolt with no more stripping of the block and a good gasket will get you on the road with no more problems.
Like I said, I quickly reach a point of "this is enough of this" and do what should have been done in the first place, consider it a "recall" repair.
Following on Martin and Gene...bolt failure from tension is what is called pancaked...in the beginning, a little more than half of the torque is carried by the first thread and then the load on each thread drops rapidly in order...
For most of us, the first thread is already gone just due to previous repairs...is OK, that original load pancakes to the 2nd thread and the rest of the load distributes along the remaining threads.
Based on what you describe, and even if you are using low head bolts on a high head...#7 is shot... as this is the 2nd "let go" you can gamble over and over...or...if it were me I'd just now helicoil them all, once and for all and not only have confidence, but also know that I could tug on that block for just about any head.
Your own opinion may vary.
I second what Tim said, just use studs.
You can not pull a stock head off with stock firewall with studs installed. The back of the head is under the recess in the firewall.
Wow - a lot to digest. Maybe restating a little. I'd had the head on a few days ago when I found my embarrassing bolt in the cylinder gaffe. The bolts were all torqued down just fine. So I remove the head, replace it with he same bolts (a new set from Langs I think, and identical In Length to the original bolts)I've methodically chased all of the bolt holes with a bottoming tap, blown them out with air and even inspected with my endoscope to see that they are clean.
So with the head off most recently, I took one of the same bolts and it torqued to 45 very surely. Am I reading right that with the head on, it's not getting deep enough into the Block? I think I will put a bolt through the head and measure how much is coming through the bottom to get an idea of how deep they will go.
I'm waiting for a new gasket so have the weekend to "measure twice" with all this stuff. I'm intrigued by the stud comment. I'll have to research a bit more. I understand well what you are recommending, however suspect I need pictures and more to fully grasp.
Yes you are correct Mark but you can place the head in place with the studs in it and double nut it down then follow the procedure. To pull the head off just double nut it again and back the stud out...if some sort of anti-seize was painted on the studs. Really how often should you have to remove the head? There is a way to do it and to fix this block problem without continually drilling the block I would get it done and be done.
I am almost 57 years old, things I do now I hope to never do again. That problem would be behind me and for the next guy to figure out. If it is that big of a problem just remove the radiator and pull the motor out the front, that would take less time than what Charlie has gone through.
Did that single hole fix on the '27. Left the head on. Made a long tap by brazing to a socket extension.
That way could tap down thru the head and clean out the existing threads down deep. The std. T head bolt only gets about 5 or 6 threads, and there are at least 9 or so in the block.
So went to the Ace, and got grade 5 bolt which is a tad longer than the std. high dome bolt for the '27.
That fixed it, longer bolt, holding in newly cleaned lower threads in the block. To be safe, measure with a rod to be sure you don't bottom out the new bolt. Worked for me, simple fix.
New longer bolt next to plug.
The only reason #7 torqued up fine without the head is because you could run it down further, and those last few threads are holding the torque. If you go to the magic stud route you will likely pull those last few threads out when you retorque the studs following your first run. Following your travails has been painful. Not as painful as for you, but it's been painful. Good luck. Personally, unless you come back and tell us you used a bolt that was 1/2" shorter than all the others, I see a helicoil in your future.
The longer bolt will work if it is not too long. If you take off the head, try putting in the bolts without the gasket If the bolt goes all the way down you can try it with the gasket on. You might get lucky. Otherwise you need a helicoil.
Sounds like a job for the Stevens T 235 Tool.
Grateful for all the recommendations (and well wishes for my travails). Honestly, this thread issue is the most disturbing / scary one to me. The rest of them go down as valuable learning experiences - and fun. I enjoy fussing with mechanical stuff as long as I don't break things like I broke the threads (I think - still have to check).
A couple questions after digesting the comments above:
Do the threads degrade just a bit every time they are torqued? Primary concern is whether the current problem is a bellwether for more of the bolt holes.
What would be the consensus of my plan:
Dry fit the head and gasket (i can use my original one removed), and get a decent measurement from the head to the bottom of the threads. Check this against my existing bolt and see if there's room to get a longer bolt in there. If I were, am I asking for trouble by torquing against just those few previously untouched threads?
If that doesn't seem like a good plan, I think a helicoil will be the best next step. That one sounds commonly used, very effective and moderately easy to accomplish. But I'm not too excited about drilling out the hole further to start that process. I don't want there to be any "learning moments".
The stud option is interesting, but only if 1 & 2 fail. And the Stevens Tool is very interesting. Ultimately, isn't it basically an alternative insert to a Helicoil? Would it be that much preferred to go through the effort to put together the required tools?
Last - can anyone provide the basic bolt spec for the head. I can certainly do it at the hardware store using the existing bolts, but having that backup info would be great too.
The Stevens tool uses inserts and also uses the head as a guide for machining. I may have one set left from the run I made a few years ago.Here a few pics of how it works. Here is the spacers installed.
The reamer in the head reaming the block.
The tap inserted and tapping new hole.
The new threaded insert installed.
The insert installed, ready for the head bolt.
Dan - Having not done too much of this sort of thing (tap & die work), would you say that this is successfully doable by a novice? If so, could you let me know if you have another set available and what the cost would be if it was for sale?
Charlie: This is an copy of a tool set made by Stevens. It is T235 Head bolt bushing set. They made some of the best and easiest Model T service tools made. The beauty of the T 235 is that you can fix a stripped head bolt in the car. That is where you strip them most of the time. I will check tomorrow and see if I still have one. Pm me when you get a chance. Dan.
Update - maybe everything is ok?
I went back to the car to check out a new torque wrench. I figured I would test it on that devilish head bolt here. I first put a bolt into one of the block holes and using my mechanic's torque wrench (very long / heavy duty Snap-ON model), torqued it down to 45 ft/lbs. All good, all held. Then I put my new, cheaper and shorter torque wrench on the same bolt. It "clicked" right away, essentially verifying that it was also reading 45 ft/lbs. Last, I took a bar type torque wrench and it got up to 45 ft/lbs. I didn't go any further - so tools ok. The long one "clicked" to 45 ft/lbs very easily and made me question the torque level. The shorter, new torque wrench definitely felt like I was really tightening well at the same ft/lbs. Sometimes better to have less leverage.
Next step, I put the head on with the old copper gasket (new one on order). I put that #7 bolt in and was able to torque it as expected at 45 ft/lbs. I doubt that the old gasket was thinner than a new one to the point that more threads held. I also looked at the threads with an endoscope. Not the perfect view, but certainly no obvious thread failure (I know this doesn't necessarily mean anything.)
I really can't explain what's happening. There's no question that the bolt didn't tighten down to spec before "releasing briefly" with the new gasket.
I think that the longer bolt would be a good idea here. I put a pin into the bolt hole in the block with the head / gasket in place. it felt as if the center of the hole was depressed just a bit (probably from the way it was machined originally. So I tried to get the pin on the edge of the bottom which would give me a shallower depth (but not by much). Not perfect, but it seems that I have a hair more than 3/8" remaining from the current bolts to bottoming out. Maybe I can find a bolt that's 1/4" longer. Should still be ok. I'll definitely re-try with the existing bolts and turn to a longer plan if I get the same stripped symptom.
I half suspect that what you thought was "torqueing" was the bolt catching on the head gasket and pulling the copper up. When the copper popped past the thread ("released briefly"), the bolt was loose again, waiting to be torqued. Bolts do not strip and then retorque to 45 ft/lb.
how did this turn out?