Can I reuse 1955 Packard 320 headbolts?

[StevenGR]

Hi guys, newbie here. I am rebuilding a 1955 Packard 320. Can I reuse the headbolts?

[Matt Harwood]

I wouldn't. Head bolts stretch and even if the threads look good, the bolts themselves may not actually be good. Many were designed for single time use (torque-to-yield). We recently had a car in our shop that had a rebuilt engine but had been in a museum for 20 years. We got it running and driving and we found that it was blowing white smoke and consuming coolant. Pulled the head and found nothing wrong and the copper gasket was in good shape. Ultimately, we learned that the head bolts had stretched just enough to keep it from sealing properly once it was warmed up to operating temperature and driving at speed.

 

Head bolts are cheap. Use new ones and be sure that it's right.

[StevenGR]

$18 a bolt... not cheap in my mind. lol but, may still be necessary. thanks for the advice

[Matt Harwood]

25 minutes ago, StevenGR said:

$18 a bolt... not cheap in my mind. lol but, may still be necessary. thanks for the advice

 

What are they made out of, titanium?

[Ben Bruce aka First Born]

Steven, I have never done a Packard. I would expect they used as good bolts as the rest of the industry.  I have never used new bolts unless the original were corroded badly. Perhaps later  [ 1990 or so ] need to be replaced, but from the '70s back, I would not hesitate to use the original. The shop manual for my 1950 Buick says nothing about new bolts.   Just my 2 cents.

 

  Ben

[Rusty_OToole]

Nobody heard of replacing head bolts until GM came out with cheezy single use head bolts in the early 80s. In the sixties and earlier head bolts were about the toughest bolts on the car and could be reused indefinitely. If you are suspicious, measure the length or line them all up like little soldiers. If they are the same length ok, if they look stretched or bent replace them.

[Matt Harwood]

That's just it--you won't see the stretching. It's thousandths, literally not enough to see with the naked eye. The original bolts looked fine. No visible signs of distress, threads good, no galling, no damaged flats on the heads. But stretched they were, ranging from about 12 to 18 thousandths too long, enough to prevent the head gasket from sealing properly when torqued to spec. We ended up using some Grade 8 bolts that cost about $3 each and were, interestingly enough, the right finish (note that vintage bolts are probably little better than Grade 2 or 3, claims of "things were better back then" notwithstanding). It's not like we shoved mangled bolts back into the holes and hoped for the best. They looked just fine. They were not. And we had to take the engine apart twice because of it.

 

Or you can use fresh head bolts (hopefully some that don't cost $18 each) and never worry about it again. Your money, your time, your decision.

[Larry Schramm]

On the older cars, was the recommendation to torque the head bolts down and run the engine and then re-torque them again?  On older engines I too do not remember using new head bolts each time the head was off.  Now that was what was cast iron heads on a cast iron block. 

 

With the cast iron block and aluminum heads many of the manufacturers went to torque to yield bolts to keep tension on the head to the gasket to the block because of the different coefficient of expansion of iron & aluminum..

Edited January 18, 2018 by Larry Schramm (see edit history)

[Matt Harwood]

Good point, Larry. The car we were working on did indeed have an aluminum head.

 

[Frank DuVal]

Yep, never bought  a new head bolt for typical stock iron head iron block rebuild here. I've done lots of them.  Even reused them on diesels. It is a good idea to clean the holes/chase threads before bolting the head down. If the used bolt bottoms out on junk in there, or has stretched, then you will get proper torque, but no gasket sealing. To check for stretch, run the bolt in to bottom, measure gap between head of bolt and block, measure thickness of head and gasket. Need room for gasket compression. The measurement should not be close! Machinist close, that is.

 

This check is very important if you mill the head!

 

I found TTY bolts on Ford products (Escorts) long before I read about them on GM. 

Edited January 18, 2018 by Frank DuVal (see edit history)

[Curti]

The original Auburn head bolts were embossed with a 'W' and were parkerized black or dark grey, they were GR2 or 3  The new reproductions are GR8. Do not torque over 50 lbs.   Do re-torque after a few heat cool cycles and again after 20 or so. 

[joe_padavano]

Some bad info in this thread.

First, prior the the 1980s, head bolts were NOT torque-to-yield.  All materials "stretch" under load.  Metals have an elastic region (where the bolts will stretch but then return to their original dimensions) and a plastic region, where they actually yield under load and take a deformed (stretched) shape.  Unless they've been over-torqued, older head bolts are used in the elastic region and thus are fine to reuse.  Of course, this assumes the bolts are not otherwise damaged or rusted.

 

As for the torque-to-yield fasteners, this is not " cheezy single use head bolts ".  This is a very specific engineering decision to ensure uniformity in clamping force. Older engines are overdesigned, with extra metal in the heads and block. Torque settings on a torque wrench are a horrible way to gauge bolt clamping force, since friction in the threads and under the head of the bolt can cause a +/- 50% variation in clamping force for a give torque reading. These older engines with extra metal could accommodate a higher than necessary clamping force to ensure the minimum installed torque was still adequate given this variation.  

 

Due to weight reduction for improved gas mileage, modern engines have much thinner castings that cannot accommodate this variation in clamping force. Torque to yield bolts results in a more uniform and repeatable clamping force.  In addition, slightly yielding the bolt actually work hardens it, which increases strength. 

[Owen_Dyneto]

Unless they've been abused or damaged, of course you can reuse your V8 Packard headbolts, they are hi grade and robust as all heck.  Hundred and hundreds of these engines have been rebuilt using the existing headbolts, can't say I ever head of a failure due to a head bolt.

[37_Roadmaster_C]

I am very mixed on the replys to this thread. I will just toss in my thoughts for consideration.  I understand and respect both Matt and Joe and their experience and technical knowledge.  In my time as a amature machinist and a car and farm fixer I have never replaced a head bolt on pre 80's engines. Matt makes a good point with the consideration that if the bolts are replaced with appropriate new bolts you will have no doubts. New high grade bolts should not cost $18.00 each. More like $2 to $5 each.  As long as the head and block are both the same metal, I would not be afraid to reuse origional bolts as long as they are not obviously damaged.  I would make sure the bolts AND threaded block holes are clean and cleared. I would also make sure to measure bolt clearance as mentioned above in case the head or block were ever milled from origional. Another thing to watch for that costs nothing is carefully count the number of turns it takes to bottom out the bolts in the block without the head. This will give you a reference point. When you install the head and tork the bolts keep a close count on the turns used. I would expect there to be several turns unused. If it is getting real close I would simply expect either the head/block was machined or the bolts had streached. Either way, new bolts should be used. I would also make it a point to retork the bolts after a couple of heat cool cycles and again after a month or so of average driving. It is a bit excessive, but a retork after winter storage could not hurt.  Just my thoughts, for what you paid for them  .

[Rusty_OToole]

"Cheezy" may be an opinion, "single use" is not. If they had to use crappy bolts to make up for other weaknesses in design, so be it. That kind of 'quality' decision is why so many people will never buy another GM product.

 

If you want new bolts ARP is the specialist in quality bolts for hi perf applications. They make up kits for popular engines, maybe they can do one for your Packard. I know for some old cars it is cheaper to buy 2 kits for a modern engine than to buy the bolts one by one. If there is a modern engine that uses the same sizes you need.

 

http://arp-bolts.com/

 

Or, here are chrome moly bolts in 5 packs you can mix n match to suit your engine

http://arp-bolts.com/kits/Bulk.php?PL=1&M=2&W=*&D=*&P=*&WS=*

 

 

Edited January 18, 2018 by Rusty_OToole (see edit history)

[joe_padavano]

34 minutes ago, Rusty_OToole said:

"Cheezy" may be an opinion, "single use" is not. If they had to use crappy bolts to make up for other weaknesses in design, so be it. That kind of 'quality' decision is why so many people will never buy another GM product.

 

If you want new bolts ARP is the specialist in quality bolts for hi perf applications. They make up kits for popular engines, maybe they can do one for your Packard. I know for some old cars it is cheaper to buy 2 kits for a modern engine than to buy the bolts one by one. If there is a modern engine that uses the same sizes you need.

 

http://arp-bolts.com/

 

Or, here are chrome moly bolts in 5 packs you can mix n match to suit your engine

http://arp-bolts.com/kits/Bulk.php?PL=1&M=2&W=*&D=*&P=*&WS=*

 

 

 

You still aren't getting it.  First, ALL cars today use torque-to-yield.  This is done purposely to improve head clamping while reducing weight.  Head gaskets are "single use". Does that mean they are also low quality?

[Rusty_OToole]

English BSA motorcycles used to come with solid copper head gaskets that could be annealed and reused so it is possible.

 

Something may be lighter, cheaper, and therefore 'better' while also being flimsy and prone to breaking. GM seems to specialize in parts that are just good enough to get by until the car is off the dealer's lot, and good enough to outlast the warranty, maybe, with luck, if you don't use the car hard. This is not my idea of high quality and a lot of Toyota, Nissan, Mazda, and Mercedes buyers who used to drive GM cars agree with me.

[joe_padavano]

34 minutes ago, Rusty_OToole said:

 This is not my idea of high quality and a lot of Toyota, Nissan, Mazda, and Mercedes buyers who used to drive GM cars agree with me.

And yet all those cars also have single-use, torque-to-yield head bolts. 

 

There are plenty of reasons to bash GM's newer products.  This isn't one of them.

 

Using an English product as an example of higher quality is hilarious.  You made soda come out my nose.

Edited January 18, 2018 by joe_padavano (see edit history)

[Rusty_OToole]

I agree, when you can't compete with a 50 year old English motorcycle on quality it is a laugh.

[Frank DuVal]

Yes, most every manufacturer for the last 20 years  uses those "cheesy single use head bolts" :  VW, Mercedes, Audi, Mazda, Ford, Nissan, Toyota, etc, etc, etc,... Why pick on GM for what the entire industry uses? As I said, I first had to buy "single use" aka TTY head bolts for Ford Escorts, when replacing those warped heads. Then I needed them for VWs, then Mazdas. I have yet to buy them for a GM product! What GM product did you need to rebuild that used them? I know GM was using TTY in 1996 for some engines, but not all. By then most of GM engines were good for in excess of 200K without needing anything head related. I've got 230 K on my 98 Park Avenue, and 260K on my 94 Caprice wagon. Still going very strong without oil burning.

 

Corvairs also used the copper head gaskets in the beginning. And you can buy them as aftermarket replacements still. Anneal and reuse!

[Ben Bruce aka First Born]

Sorry, Rusty, I think  I will stick with my 25 year old Buick. There are a LOT of GM cars from the '80s and '90s going 250000-300000 miles.  My  kids are amazed at the ride and handling when I can entice them for a ride. Beats their 3 year Altimas and Corollas all to pieces. 

 

  Ben

[Rusty_OToole]

Replaced a head gasket on an 82 Olds front drive 4 cylinder. Nobody told me about the head bolts, never heard of this problem before. Had to redo the job. Yes I am still sore. I still believe using weak bolts to avoid damaging a weak head is cheaping out even though everybody does it.

[Larry Schramm]

9 hours ago, Rusty_OToole said:

Replaced a head gasket on an 82 Olds front drive 4 cylinder. Nobody told me about the head bolts, never heard of this problem before. Had to redo the job. Yes I am still sore. I still believe using weak bolts to avoid damaging a weak head is cheaping out even though everybody does it.

 

What 4 cylinder?  If it was a quad 4 engine, then I am sure it had torque to yield  bolts. Absolutely necessary to replace the bolts, new head gasket and check the rear corner of the head where it was probably leaking.

[Matt Harwood]

10 hours ago, Rusty_OToole said:

Replaced a head gasket on an 82 Olds front drive 4 cylinder. Nobody told me about the head bolts, never heard of this problem before. Had to redo the job. Yes I am still sore. I still believe using weak bolts to avoid damaging a weak head is cheaping out even though everybody does it.

 

Not really fair to blame the car and engineers because you didn't do your homework, is it?

[joe_padavano]

11 hours ago, Rusty_OToole said:

Replaced a head gasket on an 82 Olds front drive 4 cylinder. Nobody told me about the head bolts, never heard of this problem before. Had to redo the job. Yes I am still sore. I still believe using weak bolts to avoid damaging a weak head is cheaping out even though everybody does it.

 

Sorry, but you are seriously misinformed.  They are not "weak" bolts. Take a metallurgy class.  Stretching the bolts slightly beyond yield actually makes them STRONGER.  It also means that you can only use them once.  Of course, the factory service manual on that 1982 Olds would have told you to replace the bolts.  As with any vehicle, if you don't follow the correct service procedures, you are going to have problems. As for the "weak" head, the reduction in material thickness was done to reduce weight to comply with federal CAFE requirements.  If you don't like that, get the law changed.  Don't blame the manufacturer.

[joe_padavano]

2 hours ago, Larry Schramm said:

 

What 4 cylinder?  If it was a quad 4 engine, then I am sure it had torque to yield  bolts. Absolutely necessary to replace the bolts, new head gasket and check the rear corner of the head where it was probably leaking.

 

The Quad 4 didn't exist in 1982. The only "Oldsmobile" four cylinder motors offered that year were the Pontiac Iron Duke in the FWD Omega and the Brazilian-built four cylinder in the J-car. Neither were actually sourced from Oldsmobile.

[Bloo]

There was a time, not that terribly long ago, when any engine that had a cast iron block and an aluminum head (or heads) could be expected to blow a head gasket at about 80,000 miles. Many cars, especially front wheel drive, were built this way. The reason is that the aluminum expands more than the cast iron. The head not only slides back and forth sideways with heat cycling, it also gets thicker and thinner, squishing the gasket tight when hot, and then letting some of the tension off when cold.  It seems this can only happen so many times before a fire ring on the gasket cracks, and then things get bad in a hurry.

 

Today it is common to see cars with 200,000 miles or more on an iron block aluminum head engine, still with the original head gasket. Torque-to-yield bolts (along with better head gasket technology) is the reason, Because the bolts are stretched into their plastic region, they behave like springs, keeping tension on the gasket as the head slides around and gets thicker and thinner with temperature changes. Larry Schramm mentioned this a few posts back.

 

I have never heard of replacing head bolts on general principles on something as old as a 320 Packard, but they should be inspected closely, threads checked, and measured for stretch. On the other hand, better bolts (ARP) are available today than anything offered back then (assuming you can find some to fit a 320 Packard).

 

 

[Rusty_OToole]

10 hours ago, Matt Harwood said:

 

Not really fair to blame the car and engineers because you didn't do your homework, is it?

You are 100% right. Truer words were never spoken. Just because every car I ever worked on had good head bolts I was fool enough to think this car was the same. Will not make that mistake again. I went from being a GM fan to avoiding them at all costs.

 

By the way do you do metallurgical tests on every car part you work on? And buy the factory manual and read it through from cover to cover before you pop the hood?

Edited January 20, 2018 by Rusty_OToole (see edit history)

[Rusty_OToole]

3 hours ago, joe_padavano said:

 

The Quad 4 didn't exist in 1982. The only "Oldsmobile" four cylinder motors offered that year were the Pontiac Iron Duke in the FWD Omega and the Brazilian-built four cylinder in the J-car. Neither were actually sourced from Oldsmobile.

It may have been an 84 but no newer. The engine was an inline 4 cylinder, OHV with pushrods.

[Bleach]

Many years ago I worked in a materials testing lab. We would test reinforcing steel for tensile strength. There would be grade 40 and 60 that was generally used in construction. The grade meant at what the yield strength needed to reach when tested, 40,000 or 60,000 lbs. The steel would be tested for yield strength and then ultimate strength which is the point of failure, usually expected at least 20k to 30k beyond yield strength. There was usually about 10% of stretch measured on the sample at failure.

I'm sure bolts were tested similarly and will certainly stretch in relation to the amount of torque applied. Torque to yield bolts are certainly a lower grade of steel because it yields at lower point.

Older higher grade bolts will need far more torque to reach their yield point than what is specified in normal applications.

[Frank DuVal]

46 minutes ago, Rusty_OToole said:

And buy the factory manual and read it through from cover to cover before you pop the hood?

 

No, just read the section of the part on which I am working.

 

Even Chilton's, Hayne's and Motors should have TTY information in them.

 

I too have been bitten by not following prescribed method. Mine was replacing Nissan (or was it Datsun ) rear disc brake pads. Never saw a caliper piston that was screw designed before.....  Guess I should have blamed Nissan....  Well, I did learn my lesson, and was ready when I did pads on the rear calipers of Cadillacs!

[Matt Harwood]

Can you imagine my surprise when I went to give my 1993 Mustang a tune-up and found this:

 

 

That's not a carburetor! How the heck am I supposed to replace the carburetor on that thing?!? The manual probably would have told me it was fuel-injected, but I know that's just Ford trying to cheap out and not pony up for a good old Holley 4-barrel. Stupid engineers specifying something I don't know anything about. Cars are supposed to be the way they always were, don't they know that?

 

What's worse, there aren't even any points in that distributor! Some kind of black box that I took apart before I knew there weren't any points in it. Once I realized there were no points inside, I had to buy a new one and rebuild it twice!

 

I'll never buy another Ford again, I'll tell you that much. Cheap bastards.

[joe_padavano]

1 hour ago, Rusty_OToole said:

It may have been an 84 but no newer. The engine was an inline 4 cylinder, OHV with pushrods.

 

Still the Pontiac Iron Duke. The Q4 was released in 1988.

[joe_padavano]

1 hour ago, Rusty_OToole said:

And buy the factory manual and read it through from cover to cover before you pop the hood?

 

YES, ESPECIALLY before performing a task like removing the head. Where did you get the torque values and pattern - or does the fact that the car requires a specific torque value and sequence for the head bolts further cause you to call it "cheap junk"?

 

The factory service manual is the FIRST thing I get after I acquire a car.

Edited January 19, 2018 by joe_padavano (see edit history)

[Bleach]

I have factory shop manuals for every car I own, even for my wife's Acura MDX. For the newer cars I review the manual to see if it's worth my time to mess with whatever it might need or take it to the only mechanic I trust. With the older cars, if it needs to go to the mechanic, more likely then the car will need to be sold. That's what happened with our '05 Civic two years ago. It needed a new transaxle and the cost to rebuild it with labor to R&R it was half what the car was worth. I reviewed the shop manual and the labor to remove the transaxle was far more involved than I wanted to deal with. So I sold it for half what it was worth and cut my losses. I told the buyer what it needed so I guess he figured he could do job for less than I could or was doing it himself.

Anyone need a '05 Civic shop manual?

[Rusty_OToole]

I must have at least 100 repair manuals around here some dating back to the 1940s or earlier.

 

Believe it or not I always get a manual and consult it before doing a job like that especially for the first time. Not the $200 dealer's manual but a $15 Haynes or whatever is available. I am sure I did this, and I am sure it said nothing about single use head bolts.

 

The car was NOT mine I fixed it for a neighbor (for free) because she was stuck for a car. Another reason it hurt to do it over, unpaid, and pay for new gaskets and bolts out of my own pocket.

Edited January 19, 2018 by Rusty_OToole (see edit history)

[Larry Schramm]

4 hours ago, Matt Harwood said:

Can you imagine my surprise when I went to give my 1993 Mustang a tune-up and found this:

 

 

That's not a carburetor! How the heck am I supposed to replace the carburetor on that thing?!? The manual probably would have told me it was fuel-injected, but I know that's just Ford trying to cheap out and not pony up for a good old Holley 4-barrel. Stupid engineers specifying something I don't know anything about. Cars are supposed to be the way they always were, don't they know that?

 

What's worse, there aren't even any points in that distributor! Some kind of black box that I took apart before I knew there weren't any points in it. Once I realized there were no points inside, I had to buy a new one and rebuild it twice!

 

I'll never buy another Ford again, I'll tell you that much. Cheap bastards.

 

Blame government regulations for the "added content"

[Bleach]

That's why I like old cars so much. There's little or no gubmint mandated junk.

I'd love a Packard like the OP has.

Edited January 20, 2018 by Bleach (see edit history)

[Spinneyhill]

Trouble is, if you don't have a lot of that "gubmint mandated junk", you would not be able to see 100 yards up the street in many cities (think of Beijing or Delhi) and the road toll would be at least 5 times what it is, not to mention the respiratory problems from PM10s and PM5s. Basically, there are too many people driving cars creating pollution and safety hazards. As well, half of them are below average drivers. Note that Paris has banned diesels within the inner city.

[StevenGR]

Thanks everyone for your advice...I think I will inspect and re-use my bolts....and cross my fingers.

Edited January 21, 2018 by StevenGR
spelling (see edit history)