VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Tradegy - '31 Head Cracks

I had a terrible thing happen today. I was retorquing the head bolts after installing the head a while back. I believe my torque wrench has broken and I must have overtorqued the bolts. I had them set to 80 lb/ft. Two of the bosses that hold the head bolts cracked.

Here's a picture. Does anyone think that a reputable head shop would be able to repair this? I went and got a different torque wrench and it seemed to indicate that the torque applied was over what I had it set to.

Here is a picture:

It looks fixable to me. I would remachine the top of the bolthole after to make a good seat for head of bolt.

I think after repair I would use a thin washer under the bolt head with a little lubrication. Also I believe that 80 lbs is too much-especially if re-using original bolts. When tightening in sequence probably best to do so in steps-such as first snug all bolts-then bring them up to 50 lbs and finally 60 lbs. These are my thoughts but maybe others with more experience will chime in.

These were all new bolts. I hadn't painted them yet because I was waiting for the final torquing. I'm curious if this could have caused any damage for the bolt areas under the valve cover. They seemed to be different because of how they mount, so I'm hopefully it didn't do anything to those.

I did as you mentioned and gradually increased torque. I believe the problem was that these bolts were tightened beyond 80 or perhaps 90 ft/lbs. I'm curious if these bolts have now been stretched and will need to be replaced, or if the head gasket has been compressed too much and may need to be replaced.

Hello Vetteman61,
Because of the limited surface available (weak areas) at these head bolt hole "towers" that cracked, you might want to think about having hardened bushings installed in the bolt holes during repair. The thin washer with a dab of anti-seize should help also. You should replace your head gasket when the head gets removed.

Well, I thought about being disgusted and not touching the '31 and I also thought that fixing it some random day in the future will be much more difficult than just biting the bullet and fixing it now. I only spend birthday and christmas money on car projects, so I'll have to pull something from somewhere else, but I'd like to go ahead, get it over with, and at least be able to move it out of the way when I need to get something out of the garage. With that, I made like the Queen of Hearts and went "Off with her head."

I took it to the headshop here in Nashville, "Headworks" where they do quality work. He said he'll come up with a way to fix it, but he'll need to take a look at it and consider his options.

The headshop was unable to fix the head. I then took it to my cousin who has a machine shop and he wasn't able to fix it. I then took it to a local guy that's really good and he had a solution to try. He machined down each bolt and made a separate washer for each, depending on how deep he had to machine down. The one that was cracked really bad has a real thick spacer and a sheet to tell which washer goes where. I've got some stuff to sell on ebay and as soon as I get the money to get a head gasket we'll be back in business, hopefully. My 3 year old, Rose, has recently really gotten into old cars. She knows the years of the 31, 37 and 57. When I told her that we got it fixed she was really excited about getting to ride in it again and has been telling total strangers she meets about it. haha.

Great news, hope it works so Rose can drive it someday!!!

The HEAD GASKET should never ever be re-used ....PERIOD !!!!!

If the recommended torque applied to the cylinder head bolts exceeds recommended torque, by 20 + pounds, they are scrap and most likely need to be replaced with brand new.

If not available use ALLEN HEAD BOLTS GRADE 8 and hardened steel washers underneath. Check the old bolts for stretch using a micrometer and one of your original originals.

While your at it, run a straight edge from corner to corner on the block surface using feeler gauges check for run-out . A cylinder head gasket can only fill so much .

That head gasket between cyl #4 & #5 has dark areas at the thinnest part of the gasket, have a close look to make sure there was no burn thru or leakage, can be verified with then straight edge .

mike lynch

Brandon,
Are you going to Hershey?

Bill B

After copying the picture and zooming in on it, definitely between cylinder #4 & #5 the head gasket looks burned at the thinnest part.

Also, the visible cylinders 2 of them are full of antifreeze sitting on top of the pistons. Its going to drain down into the oil pan and you definitely do not want to mix oil and antifreeze and run the motor. Use a suction tube to remove the antifreeze still sitting on top of the pistons.

When putting the cylinder head back on after the correct repairs have been done, purchase a BOTTOMING TAP and run the tap into each head bolt hole and using an air nozzle with a longer nose extension , blow any debris out. The **bottoming taps** can be easily found on ebay. The threads on the tap , go all the way to the bottom of the tool .

Do it once, do it right .

mike lynch

madmike3434 , madmike3435......

If you find out you need another head I am not that far and have a couple to choose from.

Dave

At first I thought I might be able to take the entire car to a head shop and have them weld the afflicted area without removing the head. I then realized the full extent of the damage. The antifreeze is in the cylinders because I forgot to drain the lower radiator hose before removing the head. I plan to change the oil before I start it again.

Bill, I won't be at Hershey.

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If you were using a new style clicker torque wrench, you must un-wind the wrench back to zero otherwise the wrench will not apply correct torque.

You can have the torque wrench re-set by a qualified company, cost me around $80.00 10 years ago when I forgot to un-wind it.

mike lynch..........

Guys I have great luck with a product called Muggy Weld. No it's not JB weld. Low temp welding rod and it's amazing what you do. Look them up on line and look at all the products. They also have a cooling product when you don't want heat transference.
Also look how easy it is to now repair pot metal. Again I've been a welder for 40 plus years. Truly amazing product.

Steve

Interesting

MUGGY WELD for Cast Iron