Are the late '84 thru early '86, six cylinders, the only years that does not get an exhaust gasket?

 

Are you refering to the donut gasket or the manifold to cylinder head gasket? My 84 doesn't have the donut but it does have the manifold to head gasket...if that helps any!

 

I didn`t know they made an exsaust without a donut, how does
it seal??

 

Ford has a service bulliton? out that says to not put an exhaust manifold gasket on those years. I've got a '85, 300 that was leaking bad and i was sick at the time so like a dummy i sent it to a shop to fix. Should have known better. It ran real ragged. They had installed a gasket and retimed it. After a month it was leaking again. Did a search on Alldata.com an found article #88-7-16. It said that a leak in the exhaust manifold is caused by the manifold expanding more than normal and warping. the fix is a new manifold and no ehaust gasket. I was just wondering if that was the only years that was necessary .

 

My old '85 did not have a donut, but the '86 manifold that i installed did.

 

I had sooo many exhaust and intake leak problems I went ahead and installed a double gasket. It has worked great for me, I did it almost 3 years ago...still no problems. As for the donut, My 84 doesn't use one. The down pipe off the manifold is flared, it fits over a flange that was casted into the outlet end of the exhaust manifold. As long as the studs/bolts are tight it does not leak at all. In fact after installing a new manifold with a double gasket (the original one cracked) the truck was so quiet you almost couldn't hear it running from inside the cab!

 

A double gasket? That sounds good. I think that this one is going to leak on me, one of the stud threads only had about 1/2 of them that grabbed. Thanks for the info, this is a great site...thanks again.

 

Some of the studs on mine wouldn't grab either, it still doesn't leak!

 

I cant amagin not runnin an exsaust gasket on one of those motors. There so long that it would seem the seal could break easily and leak with out a gasket. As I remember those manifolds are maching flat right, for a gasket applicaton? My buddy pkupman's idea with double gaskets is slick. And all this talk of dounuts is making me hungry......Guess I will have to get up now.

Bill

 

Dadgumit Bill! What are you doing on FTE! You drive a Plymouth! Hey guys that ole Trailduster is a mighty fine machine, I drove er a few times, it's pretty fun cruising with no roof!

 

Some of the newer cars didn't use the gaskets. My 81 monte carlo was like that, and I didn't even realize it until an idiot at a muffler shop severely overtorqued the bolts trying to get it to quit leaking after I had new pipes installed, and ruined them to where they would never again seal properly. I consider shooting that guy after I noticed my new found wonderful "clack" on the ride home .
I took it right back, but being he ruined it the first time using an impact wrench, there was no way for it to properly seal again. Thats what you get when you go to a chain muffler store with employees that should be working at the local taco bell.
I HATE exahaust manifold leaks.
Double gasket...Thats an idea...On my 68, the flange on the exhaust manifold of kind of chipped in areas. I seal ok, but not totally perfect. I've heard tell of using muffler cement and coating the new gasket with that cement, and installing it, and letting it dry. But I was kind of paranoid to try that , thinking it might harden up like cement, and be hard to get off if I need another one in the future. Maybe not though...
Anyone tried this method with decent results?
I've also heard of a solid metal gasket that is supposed to be better than the "composition gasket" that most parts stores try to sell you. I seem to semi burn those up after a while, being I have the slight leak on the engine side of the flange. What are you using for a double gasket? I've never seen one. I'd like to get my truck totally quiet some day. It's pretty close, but not quite perfect. You can hear a slight tell tale "clack" when you are goosing the engine in a high gear. MK

 

Ahhhhhhhh "Smittys" I had a 'Smitty' on my '39' Chev when I was a senior in High School. What a Sound. The girls just flocked....and so did the Cops!
GLass Pac's on my '51' Plymouth Cranbrook and Purple Hoaneys on my '41' Chebby with the Split Manifold and Buick Carbs. What wonderfull exhaust notes we had in those days.

Back to the Subject... MY 78 300 Six leaked at the header pipe. I fixed it by working a Doughnut up in there. All the rest of the gaskets involved with that manifold have to be purchased for the manifold you are stuck with.
I went to the emissions Referee in Anchorage. I told him of the problems with the 300 Six exhaust manifolds, and suggested to him that aftermarket Headers might be the solution.
He said "NO" and that's a quote! Alaska uses the California emissions program and there's no provision for aftermarket solutions to engineering problems.

 

FWIW,

When I took possession of my beastie, I noticed the exhaust manifold had been re-gasketed with a double gasket and larger, doubled washers on the studs. No leaks since I've had it and it's getting quite the workout.

Oldbones