exhaust manifold hell...

[lowtideride]

I replaced the exhaust manifold gasket on the truck and ran into a few snags along the way ( broken, rusted,stripped bolts)...

In any case I hoped to make my cab exhaust free but this has just made it worse.

When I put the manifold on everything looked tight and I torqued it to spec.

Put it all back together and took it for a drive.....the truck sounds like a wet fart, you know the old pick up truck sound. I can not tell where it is leaking from either. I felt around for air and could not feel anything. I did not hear it much from the front of the manifold more in the back of it. I know the egr cooler gasket is in question, and that the donut gasket is on its why out becuase I can feel air where the flange connects.

Im at my wits end with this truck( ill never get rid of it) but this has to make a turn for the better soon...



So is there a good trick to finding the exhaust leak? besides the hose trick. (which I just tried)

 

[brian]

sea foam it.

 

[OlympiaFJ60]

Have an assistant plug the exhaust with a towl or stack of rags. Look, listen and feel all the usual places. Don't rule out the donuts at the cat too (if it still has one).

 

[lowtideride]

Not a bad idea....thanks will give it a try tomorrow

 

[60wag]

By the hose trick.... you mean the one end of the hose in the ear trick, right?

And yes, I'd take a close look at the EGR- manifold joint. Its easy to bend the EGR flange when bolting that joint together.

 

[lowtideride]

Yulp, one ear in the hose trick.

would that be bad enough to make it sound horrible under load?

 

[Man Jerk]

I 2nd the seafoam truck. Pour it down the brake booster vacuum line. Then you can see white smoke pour out all of the leaking places.

I also bought an automotive stethescope at sears, like $14. It's got a hose, and you can hook up a rod to hear all those vibrating noises if you need it. I couldn't ever get the single hose trick to work. too much ambient noise.

 

[lowtideride]

I 2nd the seafoam truck. Pour it down the brake booster vacuum line. Then you can see white smoke pour out all of the leaking places.

I also bought an automotive stethescope at sears, like $14. It's got a hose, and you can hook up a rod to hear all those vibrating noises if you need it. I couldn't ever get the single hose trick to work. too much ambient noise.

I am going to try the sea foam method later today and see what I come up with...Ill report back then.

-Al

 

[Mace]

Wouldn't it be easier to pour the seafom into the carb?? Then you do nto have a huge intake leak and it would have a better chance of getting to the front 3 cylinders..

 

[lowtideride]

Well im at work right now, but I did seafoam it thru the brake booster.

It looks and sounds like its coming from the back of it. It was so hard to tell because there was a lot of smoke. The donut gasket was leaking and I have a new one to put in, but thats not what is make that horrible exhaust leak sound.

It seems almost like it is leaking from where the exhaust manifold is seperated( the end parts that move). What can I do about that? it looks like the gasket is leaking a little bit here and there but agian it was aweful hard to tell exactly where it was coming from. gawd im sick of this truck.

 

[Mace]

You can get replacements for those seals. Al, they are designed to seal better when the truck is warm. Was it leaking bad before you took it apart?

 

[lowtideride]

I was getting bad exhaust fumes in the cab and chalked it up to a bad exhaust manifold gasket, and upon remove I can see that it was blown/burnt thru in a few spots.

Well, I replaced it and now it is worse than ever. I just dumped some down the carb and it dint smoke enough for me to see much of anything, It smoked like all hell when pulled thru the booster line (im sure 5 & 6 sparg plugs are toast now). Nothing really seemed to be leaking from the front of the gasket but most of the sea foam wasnt reaching there also. Most of the smoke seemed to be leaking from 456 and where the exhaust maifold part swings.


Im assuming there is a gasket between there? how would one take those off? ( the ends of the exhaust manifold that move)

Im gonna start searching for a machine shop that will resurface it.

When I put this all back together is it a bad Idea to double up on the gaskets??

thanks agian...


located in hell,
-Al

 

[RallyDriver]

You shouldn't need to double up the gaskets. Jim Chenoweth always has his machinist surface the intake and exhaust manifold bolted together to ensure a good fit back on the head. While you have that off you need to look at the head and make sure you don't have any cracks at the exhaust ports You also need to make sure the heat riser flapper valve is moving freely in the exhaust manifold.

Good Luck!

Brett

 

[vtcruiser60]

You might want to check that your vacuum lines are properly routed. There is a breather hose that runs into the cabin on the passenger side fire wall. It is supposed to suck clean air, but could be so misrouted that it is blowing exhaust into the cabin.

 

[Toadhopper]

This might be just plain stupid....but have you checked the "J" pipe? Mine had a nice crack where the flange was welded to the pipe.
Toad

 

[zebrabeefj40]

Most of the smoke seemed to be leaking from 456 and where the exhaust maifold part swings.


Im assuming there is a gasket between there? how would one take those off? ( the ends of the exhaust manifold that move)


located in hell,
-Al

The ends of the manifold are sealed with rings very similar to piston rings. There are 4 pieces in each end - 2 seal rings and two tension rings. Once you pull the manifolds back off you can kinda turn, twist and pull the ends out of the center section of the manifold. Not a very difficult job other than the headache of pulling all that crap back off again.

I feel your pain. I swapped a head on my 60 and replaced the intake gasket at the same time last winter. I'm just getting it back together a second time after swapping in a different exhaust manifold that will hopefully leak less then the original did. Whatta PITA!

Good luck!
Nick

 

[lowtideride]

Thanks for all the help guys, I will swing in my local toyota dealership and see what if i can get those seals. along with loacating a machine shop to machine it.

I sure cant wait to tear back into this...

thanks for all the help and motovaaation.

 

[lowtideride]

any good tips...on this...


while taking it apart the bolt on the back of the gasket was half way stripped out (yulp the 14mm way in the back)

I got it back in but it dint seem very strong. I am just worried that if I take the manifold back off bolt will completly strip out. It seems like the PO replaced it before, because there were some bolts broken before I even touched it and some mangled EGR nuts.

 

[Mace]

The older trucks did not even have those bolts, but honestly, I would remove it and put a helicoil in there.

Has anyone tried one of those liquid thread repair jobbers? snake oil or a okay fixit measure?

Like this

 

[lowtideride]

Is there enough space back there to helicoil it? it looks like you would have to pull the engine....