Hey guys,

I have an exhaust leak at the manifolds.
What is the best solution to use?

A. Take off the manifolds clear away any gasket left over and tighten the manifold back down.

B. Or would it be a good idea to invest in a pair of headers.

This 460 has been installed into a 78 Bronco. There may be some room restrictions with the frame, starter, trany. etc...

Thanks

 

Depends on where the leak is. Is it the manifold to head area? Is is a broken manifold bolt? Is it the manifold to exhaust pipe? I have read some of the stock manifolds develop cracks.


What year?

A leak could be several areas with very different fixes. Also the 460 manifolds I think used to have usual manifold to exhaust flanges with a gasket. Later models have a cone and cup design which in my opinion is prone to leaking due to heat(like towing) softening the pipe and allowing the cone to shift.

If it is a manifold to head leak, then removing the manifold and cleaning the area and using a new gasket is a good idea. Be SURE to use some sort of penetrant on the bolts. If the manifold has been in place for awhile the bolts may be rusted all to heck and you have a good chance of breaking some, and then you have a real PITA.

I would bet someone makes headers for just your swap. If it was me, I would probably go with a good set of headers. But then you are probably not suffering from any lack of power as it is so if your stock manifold is in good condition, it may be just easier to keep it.

 

It is leaking from manifold to head, and yes the bolts are rusted badly. I am interested in using long tube headers if possible. I have plenty of HP had it dynod pushing a little over 500 HP. Headers would make a little difference though.

 

Yeah, was afraid of the rusty bolts. Best bet is to spray the bolts with a penetrant while the engine is warm. Follow the instructions, which usually say tap on the bolt a bit to set up vibrations which help the oil to penetrate. I would do this several times the night before I wanted to get to work and again before I started working on it.

Liquid Wrench works OK, Silikroil or Kroil from Kano labs works, something sounding like PB Blaster seems to be a favorite of some of the guys.

A broken bolt is a real PITA especially if you don't have any room to work in.

Remove the bolts carefully. Maybe a little heat from a propane torch may help.

If lord forbid you do break a bolt, let's hope it leaves eomthing to grab on to. Then various tricks can be tried. Some recommend heating the bolt til it is very hot and then touching a candle to the threads so they wick up into the rusted area. Some recommend welding a nut to the bolt and then removing.

If you have to use an easy out DO NOT break it, or then you really have a problem. Some recommend a reverse twist drill instead. They drill the hole and a lot of times will cause the bolt to turn out due to heat vibration, torque and luck.

If you do break the bolt, check this website for discussions on how to remove.

Good Luck,

Jim Henderson

 

500hp with manafolds?

 

If ou do swap to headers, invest in a good set of aluminum gaskets or something similar. Unless you enjoy replace gaskets. I replaced 2 sets of regular gaskets and then went back with the aluminum ones and havent had an issue since. over 3 years on them now.

 

Mine blew out a gasket, so I just pulled the manifold from the block about a 1/2", removed the old gasket and torqued it back down. The leak is completely gone.

 

Did you oput a new gasket in, or you just went bare head to manifold?

 

I removed the gasket completely and torqued the manifold back down. It does not leak at all now.

 

If you break a bolt, and have to drill, leave the manifold in place or fab a jig out of 1" steel to act as a guide. The drill WILL wander off. Don't ask how I know

 

To fab a jig, do you happen to know the bolt spacing and exhaust port spacing? I'm not sure I trust reading measurements off a ruler...

Thanks

 

I broke 2 bolts today after using PB blaster and WD40 by both spraying when hot and spraying a week ahead of time for 2 or 3 applications.

3 of the bolts had already broken off on their own so now I'm looking for options since drilling with a right angle drill is tough since we cant get a lot of leverage on the front bolts behind ths shock tower.

ANyone have any ideas on how to get them out? Can we torch them out?

Here's a pic to keep everyone from trying this at home

 

Oh man. My 460 has an exhaust leak with headers. This scares the **** out of me. I was going to get new headers and put them on but now I'm afraid to even put a wrench on the rusty old ones..

 

Oh wow . I have a exhaust leak too from the head to header connection, I'm a little worried now. Ill respray and tap them all night now. Post the removal processes of the broken bolts..

 

A buddy of mine had two broken off bolts and he took it in to a muffler shop and they just torched the old bolts out. Took them twenty minutes and charged 100 bucks but he didn't mind at all!