Exhaust manifold gasket

[NC-Fordguy]

Hi folks

I recentley replaced the exhaust manifold gasket for the second time since installing a remaned head. Also installed a new exhaust manifold with the new head. The fel-pro gasket blows out after a few weeks and I was hoping there is a better gasket out there.

Any suggestions??

 

[Anlushac11]

I would lay a straight edge across the surface and make sure its flat.

I would also check with Mike at Classic Inlines and see if he still has any of the Exhaust mainifold gaskets he used to carry.

When installing the next gasket you may want to give it a liberal dose of Permatex spray on Copper coat spray.

 

[LaGrasta]

Copper RTV is the ticket! Do a thread search to find more on this.

 

[rbohm]

Copper RTV is the ticket! Do a thread search to find more on this.

8) this, or you can get a sheet of 11 gauge copper and make your own gasket.

 

[fordconvert]

I have had the best luck with getting both surfaces flat and not using any gasket. Getting the manifold surfaced is pretty easy and cheap but if the head is messed up that may not be practical unless you have the head off and in the shop anyway.

Also using the proper type of bolts makes a huge difference. For the 6 I bought some 'ramp loc' bolts from one of the mustang vendors and have not had to touch them in a couple of years now. Before it had what looked to be regular bolts and I always seemed to have a leak. I guess part of the magic of the proper bolts is having the right expansion characteristics. Too soft and they dont hold. Too hard and they bind things up when things heat and cool. Both can lead to things getting loose.

 

[NC-Fordguy]

Tried the copper coat...lasted about a week before the exhaust leak showed up.

Was thinking about using two fel-pro gaskets and copper coating them together as I noticed the fel-pro gaskets are considerably thinner than the mr.gasket brand that I have on my 302 equipped bronco which never has had an exhaust leak

Also looked into arp bolts as I've seen those seal up problomatic exhaust leaks, but could not find an application for the ford six.

I thought about going to a header but the PTO shaft presents a problem.

I have not checked the head and exhaust manifold to see if they are perfectley flat. The head is a recent reman from Dover and the exhaust manifold is new.

Not quite sure how to solve the issue....perhaps as suggested some specific bolts. One thing is for sure the exhaust leak issue sucks

 

[rbohm]

8) actually you want to try the ultra copper rtv sealant.

 

[fordconvert]

Here is the set I used. I assume all the typical Mustang vendors have them but have not checked. Also have not checked CI lately.

Ramp-Lok Exhaust Manifold Bolt Set for 1965-1967 Ford 170/200 6-Cylinder.

Includes 2 long & 9 short correct-style bolts w/ Ramp-Lok washers to attach the manifold to the head. Ramp-Lok washers are correct for 1966-1973 models, but work great on the 1965s. Why?

Ramp-Loks were developed between Ford & a key manufacturer to solve warranty problems regarding bolts backing out in 1965. Not available at the hardware store.


http://www.mustangsunlimited.com/itemdy ... y=EMUSTANG

 

[Stubby]

Another vote for ultra copper!!! Coat each side, tighten bolts, warm engine, retighten bolts while warm, forget about them forever. 8)

Make sure your timing is set properly or you can heat the manifold to a dull glow.

 

[Eaglo]

I used the Ramp-loc bolts and the crappiest thinnest ebay gasket a year ago and haven't had any problem since. Torqued the bolts to specs and even used anti-seize compound. Also sprayed the gasket with the copper sealer.

My truck originally had a metal tab that bolted to the block. A muffler clamp to the engine pipe prevented the lower joint on the manifold from moving. These tabs are usually gone. By replacing it (from a Mustang catalogue) I've solved the leak on the bottom end of the manifold too.

 

[JackFish]

Are you using a torque wrench to tighten the bolts?
I would think it might be easy to damage the gasket by over-torqueing.
I used grade 8 bolts, a regular gasket and anti-seize. No problems so far.
Mating surfaces were milled flat as well.

 

[fordconvert]

I was told by several people that grade 8 bolts dont have the proper amount of flex in them for use with exhaust manifolds. I guess they are fine for headers because what you are bolting is so thin and steel vs the thick cast iron of a manifold. I got most of the comments from one of my trucks. I was not able to find the proper bolts and standard (GR8's) were too long so i just stacked several lock washers under the heads to match the length of the originals. Many people seemed to think that I did the washer thing to get the right amount of stretch and that it was some carefully engineered thing. After a while I just told them that it was carefully planned. I dont know what the real answer is but thinking back except for the washer project when I have used non special bolts in the past I have always had issues. Some cases even had leaks with whatever I had around to throw in but when I got the right bolts leaks went away. Also like I mentioned above when possible to have clean surfaces (like a rebuild) I have had great luck with no gaskets or sealer. Obviously getting clean surfaces may not be practical in all cases. Getting a manifold surfaced in a machine shop is real cheap and quick because they usually just hit em with a big belt sander. If you have a severe rich or lean issue you will be able to burn out what ever gaskets you use with what ever bolts you use.

Your results may vary. Do not take internally. If condition persists for more than 3 hours see your doctor.

 

[64 200 ranchero]

Hi folks

I recentley replaced the exhaust manifold gasket for the second time since installing a remaned head. Also installed a new exhaust manifold with the new head. The fel-pro gasket blows out after a few weeks and I was hoping there is a better gasket out there.

Any suggestions??

i know what you mean i cant count how many times i replaced the exhaust gasket, the metal donuts suck too

 

[cfmustang]

They are pricey, but Remflex gaskets are supposed to work wonders. I can't remember if anyone on the forums has had actual experience though...

 

[MustangSix]

From the factory there were no gaskets. Just two flat surfaces bolted together. Ford did that on everything from 144's to 460's and it works well as long as the original components stay together.

The heads and blocks tend to bow a bit over time and corrosion takes its toll. The only surefire way to get a good seal, gasket or no, is to machine the flange surface and the manifold flat.

Also, the manifold bolt tightening pattern changed in the later years. Early manuals recommend starting at the center and working your way out, but later manuals recommend starting at the rear and working forward. I guess that's supposed to pull out any warps better.

The Ford Ramp-Loc bolts are also key. Those odd washers help prevent the bolts from loosening. Split lock washers aren't as effective and will eventually lose their grip when the heat-cool cycle eventually destroys their temper.

 

[dbowl]

I was going to put a Remflex on this weekend. That was until it slid off my hood and was completely destroyed on the back end. Bent in half as well. They might be OK if you were installing with the motor out but I found it just to fragile trying to do it in the bay. I actually attempted to get it in there just to see how hard it would be (after it was trashed) and found that it would be almost impossible to do it without damaging it. To much to work it around, etc. Ended up doubling up the Fel Pro gaskets with Ultra Copper RTV, running a bead around the openings on both sides and installing it. Let it sit for 24 hours, and took it out today for a test run. Sounds great without the leak. Came home and re-tightened the bolts. We'll see how long this lasts. Also installed a metal donut in place of a worn out composite one.

 

[cfmustang]

Sorry to hear about the damaged Remflex gasket.