Head gaskets and bolts

[37redram]

Back when I last played with mopar 6&v8 engines 19550/1960 ,head bolts & gaskets were put on with out sealent.

What is mostly done presently now? This is a 56 dodge 6 cyl.engine.  Thanks to all that reply.

[Sniper]

Any thing that goes into water (coolant) gets thread sealer.  What kind of sealant on the head gasket really depends on what you head gasket is made of as well as what the head is made of. 

 

These guys have a pretty good write up on this, scroll down to see it.

 

http://www.moparmontana.com/tech-faq.htmlhttp://www.moparmontana.com/tech-faq.html

Edited November 22, 2021 by Sniper

[James_Douglas]

I have found that the paste sealant on my flat heads does not seal that well. Why, I have no idea. What I have used is the yellow pipe tape on them and I never have a problem.  I do use ARP head studs on all my engines with their washers and nuts and have for 20 years.

 

James

[Sniper]

What is yellow pipe tape?  Never heard of that.

[kencombs]

7 hours ago, Sniper said:

What is yellow pipe tape?  Never heard of that.

Locally, and I think nationally, the yellow stuff is approved for gas piping.  The normal white is not.  Works but not approved,not sure why.

edit to add link:

https://www.amazon.com/live/channel/20c19cc9-fa0a-49fb-ad85-eab0f5387354?ref=AL_DP_ILM_B_CB9-15&pd_rd_w=qka3n&pf_rd_p=2b31d73f-928a-4b36-a71e-26846268badb&pf_rd_r=QZ1WHS4XZY1G0FHE97QJ&pd_rd_r=c4f31524-4441-438d-b7b1-d27e18d5daa7&pd_rd_wg=XhyQ5

Edited November 25, 2021 by kencombs

[Los_Control]

I believe yellow pipe tape refers to the color of the packaging, refers to the grade of the tape .... yellow being suited for natural gas or propane pipe fittings.

Possibly now days the tape is actually yellow so inspectors can easily identify it?

Just a WAG because modern pex gas piping is yellow, while pex water lines is red & blue.

 

Back in the day when I was pretending to be a carpenter, did a lot of kitchen & bath remodels.

When screwing pipe joints together, I always had better luck with pipe dope.

Sometimes when working under a sink, I do not have pipe dope with me but always have pipe tape in my tool belt I would use it. Simply to save a trip out to the van to get the pipe dope. Only if I had 1 or 2 connections to make, if more connections I always brought the pipe dope.

Just always seemed 1 out of 10 or 15 joints, would not seal with tape.

 

The trick with either tape or dope, you need to apply more then you need. When you get a good amount of excess oozing out, you know you have enough.

You can get away with this on rough in plumbing under the house or sink, installing faucets & shower heads etc... you need to keep it clean and use tape.

Or spend a extra hour at the customers house cleaning up your mess after installation.

 

I suspect after all the time we spend cleaning and painting our engines, is natural to try to keep the mess to a minimal and try to apply just the right amount of pipe dope needed and no extra mess to clean up.

Myself after insuring all the threads are cleaned, I will put a generous amount of dope on the bolt. Yes it will ooze out while tightened. 

I will scoop the excess up, put it back in the can then spend the extra time needed with a rag and mineral spirits to clean the mess ... maybe touch up paint if needed.

Just my experience using pipe dope .... make sure you have more then enough to fill all the voids and imperfections.

[Sniper]

I use white teflon tape myself, pipe dope always ends up a mess when I try it.

[40desoto]

On my freshly rebuilt engine I used permatex white pipe pudding.  After letting it sit for a week, I started the engine and its started weeping in some areas.  I reapplied on these bolts and the weeping was less but never completely sealed.   
ran the engine (on a stand about) 8 times for about 15-20 minutes and the weeping stopped.  Almost like if the water or any sediment that might be in the waterjacket sealed it??  

Ive heard a few folks state that this is normal

 

[SteveR]

I use to build Trickle Impregnator machines for the electric motor manufacturing industries. We would have to heat the armatures and stators and apply a polyester resin on the windings and then maintain a 250deg temp. We had fire extinguishers on these machines. We used pipe dope on the threads It was always said if you don't want to take it apart use pipe dope. Otherwise use tape. Pipe dope does get hard after a while.

[keithb7]

This is the one I used. Says right on it for head bolts into thru holes. Gotta get the High Performance stuff? I did. 
 

Not all are rated for gasoline. This one is.  Seems to be all I wanted in 1. 
I guess we’ll see when I fire up my new engine rebuild. 
 

Edited November 26, 2021 by keithb7

[James_Douglas]

Like some said the yellow tape is for gas fittings and it is also thicker than the white tape. Seems like every time I try to use paste it leaks...

 

James

[Matt Wilson]

On 11/25/2021 at 5:17 PM, keithb7 said:

This is the one I used. Says right on it for head bolts into thru holes. Gotta get the High Performance stuff? I did. 
 

Not all are rated for gasoline. This one is.  Seems to be all I wanted in 1. 
I guess we’ll see when I fire up my new engine rebuild. 
 

Some of the guys on the Power Wagon forums have used this stuff in head bolt applications on the flathead sixes for many thousands or tens of thousands of miles with good success.

[Jocko_51_B3B]

When I put my engine together I used a BEST brand head gasket with Permatex Copper Spray-a-Gasket applied to both sides of the gasket. I used Permatex Thread Sealant with PTFE (#80633) on the head bolt threads. Sure enough I saw a small amount of moisture leaking out from under the head. I didn't over-do-it with the thread sealant so it's possible I didn't use enough of it. Anyway I pulled the head, got a new gasket, and am ready to go for attempt #2. I have two questions about thread sealant to two prior posters on this thread. If Sniper and Los Control happen to read this, thanks for taking a minute to answer:

 

To Sniper... Do you use only teflon tape on your head bolts? I'm considering using only tape or maybe tape along with a generous amount of PTFE thread sealant over the tape. And how many layers of tape work for you?

 

To Los Control...When you say you apply pipe dope until it oozes out of the threads and then you scoop up the excess, I'm guessing your engine has studs instead of head bolts. I have head bolts on my '51 so I won't be able to see any oozing.  Do you use regular plumber's pipe dope on your engine?

 

Also I found a pretty good video that covers the different colors, grades, and uses of teflon tape along with some application tips. I learned a lot from it...

 

 

And here I go again. Just got the head off...

 

 

 

 

[Sniper]

12 minutes ago, Jocko_51_B3B said:

To Sniper... Do you use only teflon tape on your head bolts? I'm considering using only tape or maybe tape along with a generous amount of PTFE thread sealant over the tape. And how many layers of tape work for you?

 

It would be best to say that I do not use thread dope on anything, tape only.  How much tape really depends on the size of the threaded connection.  3 or 4 wraps would probably be fine.  Did you go thru the heat up and retorque sequences?

[Jocko_51_B3B]

Sniper,

No I didn't so maybe I jumped the gun. All I did was go through the initial torque sequence in the correct order per the shop manual. I didn't expect to see any weeping at all from the head gasket. In any case I will definitely go through three heat up and re-torque operations this next time no matter what I do to the head bolts. Live and learn I guess. Thanks for getting back to me.

Jocko

Edited December 29, 2021 by Jocko_51_B3B

[Los_Control]

Let me be clear, my experience is with  household plumbing & in a different life, I was a off road tire repair guy and set up a shop to repair tires.

I am talking about a boiler and a steam chamber to fit large tires inside .... we need heat, vacuum & air pressure to vulcanize rubber. And a whole lot of water plumbing to operate a boiler.

I used pipe dope. I never thought about using thread tape on a boiler.

 

Now later in my second life, I was a remodel carpenter and did way more plumbing then a carpenter should have.

Under the house, Galvanized plumbing, copper fittings, whatever ... I am using pipe dope and lots of it. I do not want to go back and fix a leak.

 

Now retired and in my 3rd life, I am no mechanic but learning. I can not say I have been using blah  blah  blah on head bolts for this many years blah  blah  blah.

 

Imagine if you will, the block is drilled & tapped for head bolts when new. Then head bolts are created and they work fine together.

The tools wear out.

These part most likely were created in different shops. But as the tool wears the pitch of the thread will slightly change and open up.

 

So we end up with a issue where the bolts leak.  I think I could use 10 miles of pipe tape to stop one from leaking.

To me pipe dope is the appropriate answer to fix head bolts.

The threads simply do not match because of tools, use, age. Pipe dope is the shitz for loose threads.

 

What I have on the shelf, not saying one brand is better ... just what I bought local.

 

 

[Sniper]

It probably boils down to what you are comfortable using.  Thread dope makes a big mess for me and is hard to clean up.  Tape is a much neater job, for me.  Both work, but I prefer tape.

[Bryan]

To me, it would be a matter of where the excess squeezes out. If it's outside where I can wipe it off then fine. I would be worried if the excess comes out in the water jacket somewhere.

[Los_Control]

We all seem to agree to the point of whats left over. ???

 

I have to admit, I have never heard of pipe dope goo clogging up a cooling system.

 

Is it possible to be such a idiot that you would apply so much dope it will clog up your cooling system?

Just asking for a friend!

 

Tape works but you normally just apply a certain amount and it works.

You have a worn or mis-matched thread, you need to add more.

[Bryan]

Since the bolt threads into an open end (water jacket) maybe one could experiment on threading a bolt into a sleeve with a lot of dope on it and see how much comes out the end. I don't know.

[Los_Control]

All I can say ... being disabled for 10 years and I spend way too much time on the internet reading.

I have never once read that pipe dope clogged a automobile cooling system.

 

I used it in abundance on household plumbing under the house, same with boilers  .... Not once a peep of a problem with too much pipe dope.

 

@Bryan my only point is, I already done all the experimenting I want.

@sniper is correct with a mess when it boils over onto a fresh paint job of a new engine.

Going back 20 years working on boilers I never heard a complaint clogging a cooling system.

[Dodgeb4ya]

I never use tape on any threaded assembly...hate dealing with stringy threads of it during clean up..it can shred on old corroded block threaded holes.

For years I have used Permatex #2 non hardening paste on all threaded assemblies into coolant and oil passages.

We all have different solutions...

[kencombs]

I am the odd one, again, as I've always used Permatex #2, non=hardening sealer on threads.  Never a leak one.   Someone types faster than me!  And I'll add, the sealer goes on the bolt threads, not in the hole.  Fill about 1/2 of the thread  full and screw it in.  That usually gives just enough material in place to fill all the thread gaps.  Any excess is pushed upward into the space where the bolt necks down.

 

On the gasket sealer, you may need to check the maker's recommendation as Fel-Pro does not spec sealer on both sides, just one.  Sealers interfere with the factory applied one..

 

And, that Heat/torque cycle is important.

Edited December 30, 2021 by kencombs

[Sniper]

12 hours ago, Los_Control said:

I have to admit, I have never heard of pipe dope goo clogging up a cooling system.

 

While not pipe dope, I do know of at least one instance of too much RTV destroying a good 413.

 

I had bought one of those fancy chrome water outlets and at some point is had started leaking as the mating surface was crusty and somewhat corroded, cleaned it up put a new gasket on it. Next day, leaked again.  So I made a nice thick gasket out of the cardboard from a notebook.  Next day, it leaked again.  SO I gt mad, pulled it apart and gooped enough RTV on there is seal the Titanic, put it together, wiped the excess off the OUTSIDE and called it a day, net day, on the way to work, on I15 in San Diego rush hour traffic with my 6 yo daughter riding shotgun a freeze plug let go.  By the time I could get off the highway and to somewhere safe for my daughter to be the 413 had melted down.  It got me somewhere safe, but when I tried to start it, nada, was locked up.  Later tear down showed that the RTV excess had blocked the thermostat from working properly and that started the chain of events.

 

Since pipe dope doesn't harden I doubt any excess, such as there might be on head bolts, would be an issue.

 

As for removing old tape from bolt threads, a wire toothbrush works pretty good.

[Frank Gooz]

With all talk above about thread sealers on bolts that going to the water jackets. what about head bolt torque with any of these tape or liquid on the threads.

Is there an add to the torque needed to be 65 to 70 LBS. ?

 

Thank you