Manifold inspection

[tercle]

Where in the service manual do they talk about the manifolds?
I have one set that doesn't seem right.
The faces of the runners aren't all on the same plane.
With a straight edge across the intake and exhaust flanges, I can slip a sheet of standard copy paper between the exhaust flanges and the ruler.
That's up to .0045 "
I need to find a feeler gauge, but I am guessing the misalignment is up to 10 thousandths of an inch.

Can they be unbolted and shifted slightly?
Is is possible someone joined them together wrong?

Or are these warped?

I hesitate to try to separate them, lest a bolt snap.

[TURTCEL]

Where in the service manual do they talk about the manifolds?
I have one set that doesn't seem right.
The faces of the runners aren't all on the same plane.
With a straight edge across the intake and exhaust flanges, I can slip a sheet of standard copy paper between the exhaust flanges and the ruler.
That's up to .0045 "
I need to find a feeler gauge, but I am guessing the misalignment is up to 10 thousandths of an inch.

Can they be unbolted and shifted slightly?
Is is possible someone joined them together wrong?

Or are these warped?

I hesitate to try to separate them, lest a bolt snap.

If you look in the FSM in section EM-27 you will find the clearences and technique for using your straight edge on your manifold pack.

It seems like your clearences are a little on the excessive side.

warpage maximums are as listed
Intake- 0.2mm (.0008in)
Exhaust- .3mm (.012in)

A severly overheated motor or loose manifold bolts can also cause warping if left unattended to.

Anything listed beyond those warpage maximums is said to need the manifold replaced. With such a huge clearence differnce it would be interesting to see what you are working with. Can you post some pics with the manifold and straight edge? Also pics of distinguishing marks would also be helpful in figuring out if you have a mismatched set from some other rig.

Any chance it is a manifold pack off of a 4age engine? I am not sure if they are different but from all the swap postings the guys are using their 3AC maifolds when installing. I am guessing they are different.

Peace

[xirdneh]

when i reinstall the manifolds i put a straightedge on the face to see how well they line up
if they are out of plane i loosen the four bolts that connect the exh and intake manifolds together
after bolting the manifolds to the head i re-tighten the four bolts

there can be a problem with the two shorter bolts as they tend to seize up and attempting to loosen them will break them
if that happens be prepared to do some more work
grind the broken bolt flush with the manifold and center punch the center of the bolt
with a sharp drill bit about 3/32 to 5/32" in diameter drill thru it, keeping the hole as straight as possible
there will be a gap at the end of the bolt so you will Know when you are all the way thru
i drill succesively larger holes and use the tap drill last
i just did this today so it is fresh in the mind
my neighbor is trying to fix his friends tercel that has a blown head gasket
they broke the bolts and tried using an easyout but it broke (there was no chance for it to work but they did not ask me first)
so i gave them one of my spare manifolds after fixing it up
i have the metric tap
but you can do an american thread
probably 5/16-18

[Petros]

You should go buy a feel gauge set at an auto parts store, they are only a few $ and well worth it since there are a lot of places you will need it if you intend to work on cars.

I would not separate the manifolds if I could avoid it, I would take a large metal file to the gasket face of the manifolds bolted together. Once they are reasonably flat, I would than use a wet and dry paper and a flat surface sanding block, like a block of smooth stone or steel plate, and final sand it flat. Start with perhpas 100 grit, and than go down to 300 until you get a nice flat matte surface.

Use a block of polished granite like I show hear on my head gasket replacement repair guild thread:



wrap with wet and dry paper and use solvent like I do here to deck the block surface;

[ARCHINSTL]

Another FLAT surface I've used in the past for the process that Petros details above is a piece of Formica counter top.
I've not used it for manifolds, but for various projects in the bicycle store.
Now, this was "old" production Formica from the '70s, but I'm presuming "current" production holds to the same standard of "levelness."
You might get a piece cheaply from a kitchen renovating place, from either new scraps or from renovating someone's kitchen (the latter is also a GREAT source for homemade workbench tops!).
Tom M.

[TURTCEL]

but for various projects in the bicycle store.
Tom M.

Bicycle Shop? I am a bicycle junky. Used to have my own shop...custom builds, restoration, and standard repairs. What kind of shop are you talking about? Do you still have one Tom?

I have a lot of high dollar custom bikes that I have built and still have some in my arsenal that I have been trying to sell.

Peace

EDIT: See PM tonight/tomorrow.
Tom M.

[xirdneh]

if you have a table saw or something else with a flat top (check its flatness with straightedge and feeler gauge just like you would a head)
use spray adhesive to glue a sheet or two of Wet/Dry sandpaper to it (its that black sandpaper)
sprinkle some water on it and rub the manifolds back and forth taking care not to rock it (that might rip the paper)
keep it flat on the paper and your motions even
150-220 grit

a large sharp flat file will take the metal off too
just keep it flat on the manifold face and check the surface often to make sure you are not making it worse than it was

[tercle]

This corollary of the Petros Method is highly therapeutic.
The feedback from large chunks of aluminum and iron through a bigazz file is excellent.
I spent 30 minutes or so on this and feel much better now.

The biggest flat area I have is a 12 x 4 inch piece of Petros Method granite.

Somewhere, I have 3 stainless steel 12 inch rulers, but I can't find them.

I got the feeler gauges - two flat, one valve lash type, one brass non-ferrous type for air gaps.
But the important thing tonight is, I have a large coarse file I seldom get to use.
I hit paydirt on the recessed faces.

Tomorrow, I shop for sandpaper.
And maybe a new ruler.