The Stovebolt Site Forums The Shop Area Engine Shop Manifold/block sealing 216 engine

After a bunch of work on this old truck, I am itching to drive it around but not with the noisy exhaust that it has. I figured it was the way the exhaust pipe mated up with the manifold which was somebodies idea of a quick fix which did last for years. I took it to shop to have the right kind connector put on but he found it was my manifold leaking at the head and suggested that the manifold was warped. So I took it off and held a straight edge to and I could see maybe .020/030" of gap at the center so I took it to another shop to have the manifold planned or milled flat and true. A quick turn around, just a few hours but I was surprised to see that it had been done on a belt grinder and not a milling machine or other machine tool. I went to bolt it on and bolts seem to be bottoming out and there is still about .060" gap between the head and manifold. Looking closer, I see that the exhaust manifold is running into some kind raised feature on the block and probably why it was noisy in the first place. When I put the head on last year, I made sure that the seal surfaces for the inspection cover lined up without any step and as far as I know the only detail that needs to be adhered to when putting a head back on. So now my options are to find a new manifold set which may reproduce the problem in any case or to make up some spacers and use a double set of gaskets which seems a bit of a kluge but I am not sure what else to do, other then welding the spacers onto the manifold and risk warping it again. Has anybody else had this problem and how did you fix it?

I'm trying to figure out the same problem...

Shorten the Bolts a little bit?

I ended up seperating my Intake and Exhaust Manifolds, and closing off the Heat/Exchange 'Warm Up' Box.

I had to do this on mine, because the INtake was 1/4 inch too low to align with the Ports in the Head when Married to the Exhaust Manifold.

Seperated, the Intake then fit perfectly on to the Head.

Exhaust Manifold, the outer two Ports where snug against the Head Ports ( with no Gaskets just testing the fit ) while the inner two had about a 1/16th inch gap...which was an even, paralel, not tapering gap.

I called around about getting the Faces trued, then, decided to just use double Gaskets on the inner two.

Worked perfectly...everything went to gether very nicely and all is tight, no leaks.

I should have been a bit more clear - it seemed like the bolts were bottoming out as they got hard to turn and I could see that the manifold was no where near being drawn up tight to the head. I twas bottoming out against the block.
Doubling up the gaskets may work and I'll check that this morning. And if it is not tight enough, I may try a triple gasket.
Last night I had come to the conclusion that I would silver solder (braze) spacers to the manifold. While more work than welding, having the torch in my hand while I worked would allow me to keep the whole piece warm while I worked which would hopefully minimize warping. When finished, I would have buried the piece in sand to allow it to cool slowly and evenly.
Thanks for the tips!

I would get the proper length bolts. You can put a punch in the holes in the head and see how deep the threads are. Using extra gaskets is not the answer, they will blow out and you will be working on it again.

Have you run a tap into the bolt holes? Do as Don mentions, and avoid stacking gaskets. Aftermarket gaskets were generally made to accommodate some warping. The only gaskets really stackable are the embossed metal ones. In fact, many OEM gaskets were metal, while the aftermarket parts were composite. Don't know it the metal ones are available to be used for shims.

I bought a NORS manifold to head gasket set and the "embossed metal gaskets" were almost twice as thick as the modern Fel-Pro gaskets.

I do not like using double gaskets, but they sometimes work in this location.

TC, if you think the metal gaskets were thicker, I would guess that your measurements include the height of the embossment. The metal gaskets were normally made of 0.015 or 0.020" metal, and the embossment will compress significantly during installation. Unless you had a set with more than one layer, or individual grommets at the ports.

Sounds like wrong length Bolts.

You can use Washers under the Bolt Heads, or, get shorter Bolts, or, grind-shorten the Bolts you have.

Running a Tap in the Threaded Holes, as Woodsmaster says, is always a good idea any time one has dis-assembled some old parts like this.
Holes are often corroded inside and the Tap can clean the Threads.


'Double' is probably about as far as one would want to go.

'Triple' may be asking too much of the Gaskets, and or invite a blow-out or Vacuum Leak of some part of them.


The Flange Faces which will fit fine, would not need that or any other extra Gasket thickness of course.

When you put the Manifold assembly up against the Head Ports, with no Gaskets...and snug it down with a few Bolts and the small Holders...use some Feeler Gauges and make a sketch, to show which Manifold Ports have gaps...and, how much - what thickness - those gaps are.

You can probably solve the ones with gaps then, using Factory Type Gaskets, and some thinner Aftermarket Gaskets...as the variables.

If wishing to Braze shims on to the Manifold, the Shim material is not likely to end up anywhere near flat, and or, the thin shim material is going to warp and buckle and or float on the Braze and be a mess...and the Manifold would still need to be 'Surfaced' then to ensure the Port Flange Faces are flat on both axis.

And to Braze these, you would really have to set up an enclosed Oven of sorts, and have the whole Manifold Unit brought up fairly close to Brazing Temp.

I Brazed my old Exhaust Manifold 'Heat Riser' Box closed, using some 3/16th fitted Patches...and, I set up a long 'Box' using Hard Fire Brick, and used a 'Weed Burner' on a Propane Tank to pre-heat it.


Whether Braze or Silver Braze, the Manifold would have to be pre-heated to be not too far below Brazing temp...and once done Brazing, allowed to cool very slowly.

I had mine around 600 degrees and it should have been a lot hotter.

I was doing this at a Friends House, and I kind of gave in to Brazing it at about 600 or so...1100 would have been MUCH better, since at "6" even with a large Ocy-Acetylene Torch, the Brazing would not flow well, and was like warm Chewing Gum...and would only 'puddle' at the Cone Tip of the Torch Flame.

I have Brazed many smaller things, and I never had to put up with that...I always Heated the object to close to Braze Temp, and the Braze always flowed really nicely.

No way would you be able to Braze on thin spacers and have them lay half-way flat on the Port Faces...the Brazing will not be fluid enough to allow the Spacer to rest against the Port Face without having the whole thing close to ( or almost at ) Brazing Temp while doing it.

This would mean also that you would have to supprt the Manifold Assembly in a position where all Port Faces are horizonntal on both their exis...and even then, sounds like a Nightmare to do!

Plus how to keep them from 'swimming'? Assuming the Whole thing is hot enough, along with the use of the Torch, for the Braze to be 'fluid' enough to allow a thin layer of Braze beneath the Shim?

I do not think it will work well, as a process, or as a result.


Except that the room temerature Sand immediately pulls a lot of the heat away...

Using a Fire Brick 'oven' ( which one can assemble using Fire Brick by merely setting the Bricks up to enclose the object on all sides and on both ends ) is vastly better, using 'Hard Brick' Fire Brick, since those hold the Heat well, and will genuinely allow a 'slow cool'.


None the less, I do not think Brazing Shims on to the Faces will work well...the Shims will buckle and the Braze is going to be much too thick and irregular, and you will not have flat faces for the Port Flanges.

You will be worse off than you are now.

Just another thought: Are you tightening the bolts in the proper sequence, from inside to outside?

Since many of our members swap to Fenton duals, try an ad in the swap meet for a replacement manifold- - - -I'll bet there's a dozen or more gathering dust under somebody's workbench.
Jerry

It seems the answers to this problem are headed off in the wrong direction.
As you will note in my first post "the bolts SEEMED to be bottoming out" or that is what I thought at first. Then I realized it was the manifold bottoming out on the block and preventing any further movement and the bolts were getting tight because of that - I could see the gap between the manifold. They are the same bolts that held the manifold on for 64 years.
As far as brazing spacers on, please realize that I have been brazing, welding and silver soldering as part of my profession for about 44 years now. If I were to consider myself as an expert at anything, it would be silver soldering. As far getting the solder or braze to flow between the two surfaces, either one or both surfaces would be "tinned" prior to their actual attachment. In any case, my question was, had anyone ever repaired one that way.

I just re-read the Thread, and realized you already had all the Flange Faced 'Surfaced' by a Machine Shop.

Is it just the Bolts seeming to be 'too long' which is the issue now?

If so, if the Bolts are actually 'bottoming out' with the Manifold still having ".060" to go...then, just add a Washer or two under each Bolt Head...and, you should be fine.

Good idea Hotrod Lincoln. I was going to check with Dave Adler to see if he had one.

Can you post a pic of the raised feature?


Are you using alignment rings?

I have been welding, brazing, and silver soldering all types of metals since the early 1960's, including working as a pipefitter for the world's largest winery in Livingston California, owned by E & J Gallo. I was one of 3 people on a 46-man maintenance crew who specialized in doing cast iron repairs. I would not attempt to do what you are proposing.
Jerry

A few thoughts that can be ignored if not applicable: What is holding the manifold away from the head? Are the inserts for the intake in the way? Is the manifold hitting the block? Where? Why? It should not touch any thing that is not the sealing surface on the head. Why would washers under the bolt heads and above the clamps not work? Did the "resurfacing" change the angle of the manifold in the vertical plane? I have seen studs installed into the head, that is an option. Nuts would then be free to take up any clearance issues. Have I missed some important reason why the manifold won't fit? I am confused and still not ready to recommend welding, Silver Solder or any heating of any thing at this point.What am I missing? Again, what is the manifold hitting on the block, and why? If the alignment rings are cocked that might explain it. They would have to be extended at the top and seated at the bottom to cause this much misalignment.

I have been welding, brazing, and silver soldering all types of metals since the early 1960's, including working as a pipefitter for the world's largest winery in Livingston California, owned by E & J Gallo. I was one of 3 people on a 46-man maintenance crew who specialized in doing cast iron repairs. I would not attempt to do what you are proposing.
Jerry
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Jerry could probably weld us up some split exhaust manifolds.....:-)

I'm trying to figure what this "raised area" is that keeps the manifolds from being tight? Sounds like the manifolds are still not all on one plane to me....

John

Well, I have eat a bit of crow it seems. I took the manifold off which had been just held on loosely and used a straight edge from the head manifold seal surface and found that I should about .12" clearance to the raised features on the block so they are not the problem. Then I threaded a bolt into the head and measured the distance between the clamp and the seal surface on the head and compared that measurement with manifold. Plenty of room for the bolt to thread in far enough to clamp it. What I am sure it is now is the alignment rings on the intake passage ways. I have them pressed into the head and they function to hold the gasket in place while I slip the manifold on but apparently are not fitting into their respective counterbores on the manifold. So I will take them out and grind a slight chamfer or lead-in on them. Odd that it was not this difficult a job the first time I did it.

And yes, I know about the tightening sequence and torque values.

I think I would still try to silver solder some shims on if I had to. If the part was unusable as it was, I would have nothing to lose but some time and silver solder. I do have a gas forge that the entire manifold assembly would fit in and I could try that.

Thanks all for putting up with me and I hope you all cut me some amount of slack. I started this all while I was running a temp of nearly 101 degrees and actually should have been in bed. Seems I have some kind of urinary infection or something and the antibiotics are just starting to do their thing.

At least on my Engine's Head...the Intake Port openings, the actual 'holes' I mean, are about 1/8th inch Higher than the Exhaust Port openings.

If your Head Port openings are this way also then, you can sight along your un-mounted Manifold Port Faces, and see if the inside top edge of the round Intake Openings, are about 1/8th inch higher, than the upper inside edge of the rectuanglar or square Exhaust Port openings.

If radically 'off', then you have a problem which grinding the intake port 'sleeves' may not solve.

On my Manifold 'unit', the Intake Port holes were about 1/8th of an inch below the Exhaust Port holes.

It would have fit prefetly if mounted up-side-down!

Meaning, as still assembled from the Factory, my Intake-Exhaust Manifold 'unit' was seriously 'off' and the intake Manifold Port holes were about 1/4 of an inch too low.

I have no idea how the old thing even ran that way previously.

Anyway, I seperated the Intake and Exhaust Manifolds, at the Heat Riser Box, in order to allow them each to fit the Head Ports properly.


Too...try your Manifold fit to the Head with no Gaskets, just to see if all the ports are in fact meeting the Head Port Faces with no 'gaps'.

Vertical align of Intake and Exhausr Port flanges/faces, being another issue.

Once you have a manifold decked or machined you need to look at the alignment rings.
They may now be too think and need to be dressed down.


Going together leave everything loose including the 4 fasteners for the heat box.
Then torque everything in sequence per the manual.


The torque value is very low

Thanks for all the help with this. Grinding the lead in on the alignment rings did the trick and the engine is now running quietly and smoothly, with no perceptible exhaust gas leaks at the manifold. I did not have any sockets that would fit on the inner bolts and the torque wrench so I did those with an open end and a guestimation. I think I need a crow's foot type wrench for that.

A few of the oldtimers I worked around in the 1950's had a home-brew tool made from a box end wrench bent into a rectangle shape to straddle the intake, with a socket welded onto the open-end part to plug the torque wrench into. Everybody else's approach was "Give 'em a good grunt- - - -what's a torque wrench?"
Jerry

buy a torque adapter off the tool truck they come in all sizes and use a touch of anti-sieze on the bolts and clean em good on a wire wheel run a tap thru all holes. manifolds warp because of heat cycles 1100 degree exh coming out. even when rebuilding a v 8 you better resurface all the part mating surfaces especially the intake&exh manifold and block they will all be warped cast iron or aluminum it will be done at any quality machine shop who rebuilds motors if they know their stuff a starter wrench will work like the old guys heating up a wrench and bending to the shape they want i got a few in my tool box.now i got 13 posts

You'll want to be ever so careful using a tap... unless the threads are stripped out. Instead a thread chaser would be better suited to help reform any slightly damaged threads

I did use anti seize on the bolts. The threads in the manifold were all good and no chasing was required. Thanks again for the help!