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drnittler
10-12-2009, 08:20 PM
For my 61 lark, I had the cylinder head rebuilt professionally. New everything. Everything was checked for flatness. When the head gasket was put on after 200 miles there was a slight leak and the shop redid the head gasket.
After running the car 500 miles I began to notice a extremely small hairline leak in a very small spot in the headgasket area. When I warmed the car up ithe leak went away. The oil is not mixed with antifreeze and the antifreeze is not in the oil. Plugs are clean and no sludge in the oil cap. I checked a couple of cylinderhead bolts and they are tight.
Questions: Is there something I can put into the cooling system to seal this leak up? I don't want to take it apart again.
Sold I retorque it again?
This car has not had lots of use. Would running it more often solve some of these problems?
Thanks for the help.


David G. Nittler

62SY4
10-12-2009, 09:16 PM
After 500 miles the head NEEDS re-torqued, and the valves re-adjusted! What type of anti-freeze is in it? Only use the old fashioned green stuff.

Jon Krimm
1962 Lark Sedan
http://i542.photobucket.com/albums/gg440/62SY4/carstude.jpg
1961 Champ

drnittler
10-13-2009, 07:35 AM
Should I torque it hot or cold?

David G. Nittler

jallen
10-14-2009, 02:36 AM
Cold, it would also be a good idea to clean the holes with a thread chaser or tap and make sure the bolts are seating correctly. You
might want to oil the bolt threads as well.

DEEPNHOCK
10-14-2009, 06:51 AM
That cleaning/chasing/oiling should be done during the rebuild.
The bolt torque should be checked afterwards, but don't remover/reinstall/retorque.
Just re-torque using the inside out clockwise spiral pattern.
The service manual covers this.
HTIH
Jeff[8D]


quote:Originally posted by jallen

Cold, it would also be a good idea to clean the holes with a thread chaser or tap and make sure the bolts are seating correctly. You
might want to oil the bolt threads as well.

jclary
10-14-2009, 07:17 AM
I agree with Jeff on this as long as the threads were cleaned and chased at the rebuild. If not, then the ideal thing to do would be to remove the head, clean and chase the threads, reassemble with a new gasket, give it a couple of days of "run time" and re-torque following the manual sequence. If it leaks after that...the head or the block has to have a problem. It is as simple as that.:):):)

John Clary
Greer, SC
http://i518.photobucket.com/albums/u346/jconln/HPIM0372-2.jpg
Life... is what happens as you are making plans.
SDC member since 1975

drnittler
10-14-2009, 08:23 AM
Bolts and threads were cleaned. So I just retorque. But retorque cold or hot?

David G. Nittler

jclary
10-14-2009, 08:35 AM
COLD

drnittler
10-16-2009, 01:45 PM
Update: I retorqued the head. I found all bolts ok except the front bolt that goes into the block and holds the valve cover to be stripped at the end. The front hole in the valve cover. (I did not do the work myself, I wish I had!!!!)
I found out because the bolt in question, would not touque or tighten up. There was threadlock on the bolt and the very end was stripped.
Is this a problem because I alrady drove the car 500 plus miles?
Like I mentioned antifreeze and oil have not mixed up and the seam leak seems to have vanished.
I just ordered a new bolt and when it arrives I plan to clean out the hole, fish out potential metal filings from the hole with a skinny magnet, and slowly insert the bolt.
I figure if it tightens without resistance it should be ok.Does this sound like a plan?
Advise is appreciated.
It seems like I've repaired this car more than drive it of late.

David G. Nittler

warrlaw1
10-16-2009, 02:20 PM
Good time to consider a helicoil in that hole if it won't take the bolt, but if it's not leaking, now......

drnittler
10-16-2009, 03:09 PM
Was there a continuation tot the last quote. if is is not leaking now...?
It is not leaking now.....no antifreeze on the bolt where the bolt come from, just some oil.

David G. Nittler

62SY4
10-16-2009, 06:15 PM
So, If I'm reading this correctly, the bolt in question is one that goes through the rocker arm shaft stands, with the stud on top for the valve cover, Right? Not to scare you, but you must be cautious with the center bolts, because thats the oil feed for the rocker shaft. Make sure that hole is clean before you put the new bolt in; blow it out with some air as best you can, watch you will get a face full of oil.

Jon Krimm
1962 Lark Sedan
http://i542.photobucket.com/albums/gg440/62SY4/carstude.jpg
1961 Champ

drnittler
10-17-2009, 05:06 PM
I think the problem is the tip end of the bolt. I don't know how it got stripped. I am hoping the new bolt will solve the problem. I am hoping to it without removing the head.
Any thoughst?

David G. Nittler

Dan Timberlake
10-18-2009, 01:28 PM
The engine builder/shop owes you a proper repair, if you trust them anymore, which would be real hard for me to do.
Especially if they offer the old dodge that " Oh, we had the new guy install the heads, but we fired him ". Even if its true, it puts the entire engine assembly in serious question. Bad head installation results in various leaks. Bad rod or main bearing torque can result in a catastrophe down the road.

I'd compare the length of the failed bolt to another proper rocker stand bolt. Also the length of the new bolt to the failed bolt.

The happier possibility is the bolt was just too short, and did not provide thread engagement = 1.5X or even 2X bolt diameter in sound thread material necessary for heavy duty bolting in cast iron. I'd expect the remaining block threads may have died along with the bolt threads.

One unhappy but real possibility is the first half inch of the threads in the block were stripped, so only the threads at "the tip end of the bolt" were available for doing any work, and they were too few to sufficiently handle the substantial but necessary head bolt torque. Again, I'd expect the remaining block threads may have died along with the bolt threads.

If these bolts were not involved with oil feeding, the new bolt should slide to a depth where the end of the bolt is in line with the block deck, but no deeper. If it slides in deeper, it would confirm the upper block threads are missing.
Kind of like the "1/8 in. min." dimension here
http://www.plantengineering.com/photo/88/88242-ple03055571f2.gif

But, as mentioned by others, If the bolt is involved with oil feed, then the threads are probably recessed below the block deck surface.
Regardless, when the bolt first engages the threads, the bolt head should be at least 1.5 diameters above the rocker stand.

drnittler
10-18-2009, 08:59 PM
Thanks for the help
So what are my options?
Can I run the car this way for a while?
or
I would I repait this problem?
Thanks.

David G. Nittler

drnittler
10-18-2009, 09:00 PM
Oops How do I repair this problem?

David G. Nittler

62SY4
10-18-2009, 09:09 PM
Well, while you wait for your new bolt to come, and since you need to retorque again anyway, Why not just pull another head bolt out from another rocker shaft stand and try it in the buggered hole? Clean up the hole and try another bolt you already have, that should be an indicator or how to procede.

Jon Krimm
1962 Lark Sedan
http://i542.photobucket.com/albums/gg440/62SY4/carstude.jpg
1961 Champ

Tom B
10-18-2009, 09:25 PM
I wouldn't run the car.

Oops How do I repair this problem?

Remove the screw. using a piece of stiff wire, measure the total depth of the hole.

If the hole depth is almost twice the diameter of the screw longer than the removed bolt, it can be salvaged.

However

Unless you are quite comfortable with mechanical work, find a competent machinist to repair it.

If you are comfortable doing the work, remove the head, (after draining the coolant from the radiator and block. Stuff waste rags in the two adjacent cylinders and all other holes, tap the hole to full depth, first with a plug tap then with a bottom tap, vacuuming or magnet cleaning the hole each time. Secure a grade 5 or grade 8 screw of the proper lenght (1/4 in shorter than the wire lenght.)and with a hole trough it for oil to the rockers. Don't forget to keep the pushrods in the order they were in the engine. You will need a new head gasket, too.

If the hole is stripped farther down, than the top 3/8 or so, it will need a heli-coil or a thread insert installed. Since this hole is probably open to the crankcase, the engine should be removed and the pan removed so that any iron crumbs can be removed. This isn't a back yard job. Also, the clearance between the hole and the water jacket or cylinder wall will have to be considered. If there is no clearance, a new block will be needed. If this is the case, I would approach the shop that was responsible for recompense.

[img=left]http://www.alink.com/personal/tbredehoft/Avatar1.jpg[/img=left]
Tom Bredehoft
'53 Commander Coupe (since 1959)
'55 President (6H Y6) State Sedan
....On the road, again....
'05 Legacy Ltd Wagon
All Indiana built cars

62SY4
10-18-2009, 09:45 PM
quote:Originally posted by Tom B
Secure a grade 5 or grade 8 screw of the proper lenght (1/4 in shorter than the wire lenght.)and with a hole trough it for oil to the rockers.

There is no 'hole' the bolts have a special necked down shoulder.


quote:Originally posted by drnittler
I found all bolts ok except the front bolt that goes into the block and holds the valve cover to be stripped at the end.
The bolt in question I believe is the one that is 7/16-14 x 8 1/4and has about 1" or thread and then had a built in stud with 5/16-24 thread for the rocker cover. I think the p/n is 527718

drnittler
10-19-2009, 08:52 AM
I am waiting on the bolt to compare them. I ran the car in place. No more seam leaks...weird..
Not sure what th3e story on the bolt is. I'll have to compare the other bolts.
Does anybody know who sells 61 six cylinder blocks?

David G. Nittler