head bolts tight

[Jac]

Today I wanted to remove the head of my engine. But I could not get any of the bolts out. I did not put much force for long time on them, afraid breaking them. Does anyone has some advice how to remove these bolts carefully.

Or is it better not to remove the head? I want to clean the valves and replace the head gasket.

 

[Plymouthy Adams]

If you wish to service the valves and seat surfaces...you have no choice but remove the head.  As majority of the bolts enter into the water chamber they do set up a bit and combined with the initial applied torque..they can be set firm but should break free. easy enough...it will require a bit of uumph from you....get shed of the impact wrench...use a breaker bar....even steady pressure will do the trick

Edited July 24, 2020 by Plymouthy Adams

[Sniper]

I find that sometimes tightening them first will help them loosen. 

[kencombs]

1 hour ago, Plymouthy Adams said:

If you wish to service the valves and seat surfaces...you have no choice but remove the head.  As majority of the bolts enter into the water chamber they do set up a bit and combined with the initial applied torque..they can be set firm but should break free. easy enough...it will require a bit of uumph from you....get shed of the impact wrench...use a breaker bar....even steady pressure will do the trick

I respectfully disagree.  Used properly , an impact is far less likely to break or  strip.  Run it forward for a few raps, then rev.  If it starts to bind, stop, oil, them run fed again.  Oil and rev . 
 

I don’t know how strong yours is but my air would knock those out with ease. 
 

installation is where I go back to hand tools as I want to know if one is not turning freely. 

[keithb7]

I cringed last time I removed head bolts. They all came out fine! I had no visual rust, so overall they were pretty clean. After valve work just exactly as you are doing, I installed all new head bolts to be safe. I torqued them down, then drove car to get everything hot a few times, then re-torqued them again.  The second re-torque I was pucker'd up as I gave them final stretch again. I could almost hear them wincing in pain. All turned out good though. That was 3 years ago. Been reliable and great ever since.

 

Some little tricks I might use on stuck bolts....A few mild raps on the heads with a hammer might break up come corrosion. Heat, can move things too. May not be possible with the longer bolts that go down into the block.  Could try propane torch (as its not too hot) on a stubborn bolt head for a while. Won't hurt to try if you get nervous with a breaker bar. It wouldn't be too hard to twist these bolts in half with a breaker bar. 

Edited July 24, 2020 by keithb7

[Plymouthy Adams]

1 hour ago, kencombs said:

I respectfully disagree.  Used properly , an impact is far less likely to break or  strip.  Run it forward for a few raps, then rev.  If it starts to bind, stop, oil, them run fed again.  Oil and rev . 
 

I don’t know how strong yours is but my air would knock those out with ease. 
 

installation is where I go back to hand tools as I want to know if one is not turning freely. 

and with your disagree I agree in a limited manner....as he has ultimately used the impact driver/hammer...odds are it has been somewhat effective in shocking the threads...but it is probably not strong enough to do the job...I would again, use the breaker bar and get them freed up a bit..then if he likes go back to the impact driver/hammer your method of back and forth will be much quicker and easier...but on initial movement....I have a much better feel for loosening bolts by hand with feed back given to you by the tool than with an impact gun...

[soth122003]

I'm kind of in agreement with Plymouthy on this one. If the head bolt installation is not know to you, i.e. are they original, did the P.O. install them right and retorque, were they treated with a sealer before install, then I would use a breaker bar to loosen. If the bolts are known to you i.e. you installed them 5 years ago properly, they were new on the rebuild and so on then I might use the impact to remove them.

 

Joe Lee

[Sniper]

One thing to add regarding the installation, always clean the threads in the block out.  I bought a set of thread chasers recently just for my flathead work.

 

Thread chasers are designed to clean and remove any burrs or nicks without undercutting the good threads.  So you restore the threads to usefulness without weakening them.

 

US made no less, which I always try to do.

 

https://www.amazon.com/gp/product/B00DTEFSWY/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

 

 

[Loren]

I agree with Kencombs, I've broken more bolts with ratchets and breaker bars than I ever did with an impact.

An impact uses small jolts to break the fastener free, just a whole lot of them close together.

When you lean on a breaker bar that's way too much torque for some things.

The issue with head bolts is corrosion on the ends, especially if the head has been milled.

For my project I am running a tap down each hole (highly recommended) and using tread sealant. You can use LocTite because it isn't anywhere near as strong as corrosion and it keeps that out. If you use studs (also highly recommended) only screw them in no further than one thread into the water jacket. ARP studs have a nice flat top and an Allen wrench broaching so you can "dial them in." I made a card board gauge to make them all the same height.

 

[Tooljunkie]

All good points made. 
i have a cordless impact as well, the vibration they put out is helpful to get things started. I have resorted to air hammer with a bumping head to give head bolt a rattle, seems to help but can destroy the head bolt if you get too aggressive. If bolt is rusted into head this method works extremely well if pouring water around bolt. 
turns rust to mud. But water wont do a thing if you use penetrating oil first.

if engine runs, refill cooling system, fire it up and get it hot. Loosen one bolt, snug it back up and move on to next one. Then remove head. 

[Jac]

Thanks guys, great tips. I first used my 'own made breaker bar' with this I manage to get all bolts loose and then got them out with the impact.

Do you think I should replace all bolts?

[greg g]

Pioneer order from their website or through a local machine shop. Around a buck each.  They are a small plock Chevy application but work fine.  45k on mine since installed.  Take one of your old ones, clean it up with a wire wheel, the with a Dremel, cut three vertical slots vertically through the threads.  Use it with some clean oil to chase the threads. I followed that up with a spiral brass wire brush and pb blaster chucked up in my variable speed drill and ran it up and down like you would a home.  You will notice the heads of the pioneer bolts I'd smaller than stock but no worries.  Also you probably have three or four bolts with the heads tapped to accept a short bolt.  Clean them up and save them.

 

You can stick those tapped bolts threads down in a far of vineager. A day or two will clean them up nicely.  

 

When you reinstall there is a tightening sequence and a three times around with increasing torque load.  When you get there, inquire for that info.  As you can see the head gasket material between the paired cylinders is pretty thin.  The proper procedure assures good seal and longevity of those areas.

 

Are you rolling the engine over by hand to see if you have ant stuck open valves???  Very common when these engines sit for long periods.

[greg g]

In the pic of the bolts, grade 8 left, stock center, pioneer right.

[Plymouthy Adams]

refrain from grade 8 common..there is no undercut and without this undercut you may never get them back out of the engine later...

[Sniper]

lol, nah those head bolts are fine, for tossing out the sunroof when you have a tailgater.  I bought a new set for my faltty, when I get around to putting the Edgy head on.

[keithb7]

My understanding is some hardware at final toque, the bolt gets little stretch. The bolt elongates and then locks into place. Once the bolts are removed, tension released, the bolts have served their purpose. It's a one shot thing. They won't stretch and retain tension ever again like the first time. I wonder if this is the case with cylinder head bolts? I suspect so.

[James_Douglas]

Pioneer had a few boxes left some years back with the larger head. I got them, but did not use them. I use ARP studs.

 

I would always use new bolts or studs on an engine after decades of use. Cheap insurance on head gasket failure. The poster who said to get a "cleaning tap" is spot on. Always chase the threads and do it with a lot of tapping oil. Go in a quarter and a turn and back it up a quarter of a turn. Go in a half a turn and back up a quarter of a turn and so and and so forth. Do not just turn, turn and turn. If you want to do it the absolute "best way" go in a quarter of a turn, pull the tap out, clean it and go the next quarter in a so so on and so forth.

 

Just keep adding oil as you go. It makes a big difference in chipping of the metal as you go through.

 

One thing, I found that paste sealers have not worked for me that well in the flatheads. I use yellow Teflon tape on the threads of my ARP studs to get a good seal. I noted on several of the engines I have taken apart that water can work its way up to the head of the bolt and seal there...the shafts then want to rust and cause issues years later then it is time to pull them apart. Hence, why I like to get them sealed at the lower threads if I can.

 

James.

[Young Ed]

38 minutes ago, keithb7 said:

My understanding is some hardware at final toque, the bolt gets little stretch. The bolt elongates and then locks into place. Once the bolts are removed, tension released, the bolts have served their purpose. It's a one shot thing. They won't stretch and retain tension ever again like the first time. I wonder if this is the case with cylinder head bolts? I suspect so.

Modern bolts yes. Or flatheads no. I'm using used bolts in both of mine and they are fine. Just inspect for rust and defects.

[Plymouthy Adams]

this stretch is common with the angle torque placed on bolts for aluminum head application....it is very easy to verify stretch with edge to edge of a new bolt and or thread gauge...with the amount of rust shown by you in the one pic...if all are equal to this...on after a total cleaning and inspection could one determine their fit and fitness.  New bolts from Summit (brand x in a box) is not going to break the bank and in truth, some things you should never skimp on.   These heads require lower torque values...there is no need for off the wall high end brand name stuff like ARP unless you wish just to drop the name when chatting of your build.

[Loren]

James Douglas has some good points. I had a Model T Ford someone had torqued down bolts (I won't even call them "head bolts") that were too long and cracked the bottom of the blind holes they were in. Coolant came out of the top and was quite alarming. I got a set of proper head bolts and did exactly as James said with teflon tape. Problem solved.

For those who plan or aspire to putting aluminum heads on their engine just a word of caution.

Lincoln Zephyr V12s had aluminum heads and studs that were very problematic to get off. The heads welded themselves to the studs and you couldn't take either apart.

Finally Lincoln came up with a thin wall hole saw that you put over the studs to clear them. Afterward you could just lift the head off.

I personally had to deal with the Triumph engine (early SAAB 99) that had long studs put in on an angle. You could pry the head up about 1/2 inch until it hit the cam chain, then you took a Sawzall and cut them off. Amazingly it was no big deal to pound them out of the head with a long punch and take the stubs out of the block with a vice grip.

The point of my story is when you use studs you should be very careful to use best practices to make certain they seal in the block especially with aluminum heads. I've often thought of using Spray Anti-seize compound in the head after the first stage torque but boy is that stuff messy.

Bolts don't hold as well but they usually come out easier. ARP studs are very expensive but are the best you can get, if you use them right.

[Sniper]

All bolts stretch to work as designed.  the "one time use" ones are called torque to yield.  And are the latest thing in head clamping, there is some engineering benefits to it, essentially a smaller bolt can be made to work, saving a few ounces of weight per bolt and are said to provide a more consistent clamping force.  But like anything you have to install them as specified.  They seem to work best with aluminum heads and a gasket that doesn't relax, like MLS or maybe even copper.  

 

Old school head bolts like ours still stretch to clamp, but do not go into plastic deformation like TTY and are reuseable.  Some say TTY head bolts can be reused, I tried that once and ended up have to do yet another head gasket change this time with new TTY head bolts on my wife's Neon.  It was worth the added $40 or so for new TTY head bolts than have to fool with the headgasket twice. 

 

Not sure if there is an OEM TTY headbolt that would work on our flatties, I couldn't find anything that looked promising but I didn't dig real deep into it.

[Loren]

Years ago in another lifetime, the cars I worked on had "Head Bolts" then they got these funky things that you torqued to a figure (90 lbs if memory serves but I always double checked with the book) then you took a breaker bar and twisted them another 90 degrees! I used to plan my day so that after re-torquing a new car's head at the 1,000 mile service, I went to lunch. That was exhausting!  The factory said the bolts could be re-used through 10 cycles and the question I asked was who was counting? Their idea was that 10 times covered the life of the car. The last bolts they used were even stranger in that the threads went way up towards the head and about three times the length that threaded into the block. These were the Torque to yield bolts which are used once and thrown away with no re-torquing ever.

 

One of my pet peeves is that cars nowadays are not made to be fixed or repaired.

They are intended to be replaced.

The early Toyota FJ Cruisers (and 4 Runners) had a weak rear end (they put a better one in later). This was a truck my daughter drove so I was tasked to fix it. All the parts I needed had to be special ordered (bearings and seals). I asked the parts counterman why they didn't stock them. He said the techs they had just replaced the entire 3rd member, because no there could fix one! So what was the cost of an entire 3rd member? $3,600! Just for the part. The local wrecking yards price things based on demand and the later HD axles bring $1,600!

Makes you appreciate your old Plymouth! There's a Craigslist ad for pre-1955 Mopar rear ends (7 of them) price? FREE to good home.

[kencombs]

8 hours ago, Loren said:

Finally Lincoln came up with a thin wall hole saw that you put over the studs to clear them. Afterward you could just lift the head off.

 

The point of my story is when you use studs you should be very careful to use best practices to make certain they seal in the block especially with aluminum heads.

The old time local machinist in town had that hole saw, actually several, as he used them on flathead Fords with aluminum heads.  His were not a FoMoCo product but an aftermarket version.

 

A lot of that issue stems from the previously mentioned coolant seepage past the threads and resultant corrosion buildup.  If I were to use an aluminum head on one of my old engines, I think I'd use some Noalox paste on the shanks, in addition to the thread sealer.  It is sold for use on aluminum wiring.  Corrosion in that application has been a big problem.