Exhaust Manifold Gasket mantenence

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Im talking about re-tightening the gasket after a new install.

I installed a new exhaust manifold gasket and I have been re tightening it every morning for a few days. I am wondering what the normal or recommended re_tighten interval is.

 

[xctasy]

Im talking about re-tightening the gasket after a new install.

I installed a new exhaust manifold gasket and I have been re tightening it every morning for a few days. I am wondering what the normal or recommended re_tighten interval is.

There isn't a Ford one.

See http://classicinlines.com/HeaderInstall.asp

One of the most common problems with the small six is blown header gaskets and/or exhaust leaks. However they can be minimized by following proper installation procedures. The use of locking bolts may help, but even then, leaks can and will occur if you don't torque the header flange bolts (or studs) properly. We also prefer studs over bolts, but that's our personal preference. Bolts will work just as well. The use of a high quality gasket is also very important.

torque sequence

Once you have the header on and all the bolts or nuts started, snug them down. Do not over-tighten. Lightly torque the bolts (or nuts) down by starting in the center and work outwards in a circular pattern. Then go back and tighten them down a little more using the same sequence. Make one more pass, only this time torque them down to the final recommended torque specs. Next start the motor and let it warm up to operating temp, then shut it down and let the header cool down completely. Make another pass, again starting in the center, working outwards. Repeat the cycle (warm up, cool down, and re-torque) one more time. The last step, which most people forget or ignore, is to run the engine thru several warm up and cool down cycles, after which you re-torque the bolts or nuts one more time. Again, make sure you start in the center and work outwards. That should do it. However it doesn't hurt to check them a couple times over the next few weeks or months, depending on how much you drive. The important part is running the motor up to operating temp and letting it cool down, several times, before re-torqing.

This photo shows where stock gaskets
commonly leak, and eventually blow out.

Just a peak load of bolt tension. You keep going until the bolts have a peak torque on them which is measured with a standard amount of lubricant on them (nothing but a smear of engine oil). On an exhaust, that bolt oil content or friction factor changes, so Ford have a one application rule, without as gasket. That figure is 20-24 lb-ft as per Torque Specs http://classicinlines.com/SmallSixSpecs.asp

What you cannot do is keep lubricating them with WD40, and torquing them right away. Then the peak toque will change.

That's why Ford don't use gaskets, it would take forever to torque them up.


But you can do this if you are patient.



The English used to use yiedling brass nuts on studs to allow gaskets to be fitted, and constantly torqued up. On a Ford six, that would casue problems. This was a 1958 FE engine solution, continued on the 144/170 small six, and the 200/250. Same design team.

 

[toadpad]

I installed a new gasket and have driven the car about ten times now and I have been able to re tightened the bolts after it cools after each day. im hopping that one day I will be able to drive the car without having to re tighten the manifold afterwords.