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Discussion Starter #1
Bummed to say the least, had the intake and exhaust manifolds machined and media blasted back in january and have just tried tonight installing them only to find that the exhaust manifold isnt fitting flush at its base.

front shot


Either I have it misaligned somehow or this manifold needs replacing

I havent put the 2 nuts back on the carb area yet but I dont think that will help me much.

engine pic
 

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hey if that wont work right i have an extra intake and exshaust for sale let me know.
 

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Discussion Starter #4
looks like they machined ALOT off of it!:turn:
Yeah he scalped it, had to though it was leaking bad from the front. There was slapback and sputter while driving on a coast, meaning when I wasnt having to accelerate.

heres some pics just after they were pulled

 

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Man that sucks. I hate when stuff like this happens. Even to other people. And it looks like you've done a wonderful job otherwise on everything else. If it was machined true, it should fit flush. Is it like this on all the flanges or just this one? Was the intake AND exhaust manifolds bolted together as a unit when the flanges were machined true? That way they would ALL be on the same plane. Was the head side also machined true? I wonder if it would be possible to double up on the manifold gasket to fill the gap? Or even pull the dowel pin off the end and thread it for a bolt or threaded stud and tighten down on it to close it up.
I would talk to the machine shop that did the work and see if they have a warranty or somthing they could do to fix this. It almost looks like it was machined at an angle.
 

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Discussion Starter #6
Man that sucks. I hate when stuff like this happens. Even to other people. And it looks like you've done a wonderful job otherwise on everything else. If it was machined true, it should fit flush. Is it like this on all the flanges or just this one? Was the intake AND exhaust manifolds bolted together as a unit when the flanges were machined true? That way they would ALL be on the same plane. Was the head side also machined true? I wonder if it would be possible to double up on the manifold gasket to fill the gap? Or even pull the dowel pin off the end and thread it for a bolt or threaded stud and tighten down on it to close it up.
I would talk to the machine shop that did the work and see if they have a warranty or somthing they could do to fix this. It almost looks like it was machined at an angle.
Yeah I'm betting thats what happened --the angle theory. I am going to remove them and bolt them together first before I try to install and see if that would make a difference. I doubt that if I bolt them together first that the bolts will connect properly, I had to lift the intake up a tad to get the center bolts to start threading. The guy that did them charged me 40 bucks altogether to media blast, machine, drill out the thermostat choke screws that broke off and retap, and prime coat them. Seems like a fair price but I doubt he will warranty the work.

I will try to see if connecting the two together once I get them off will show how off they might be. Wish I would have checked this months ago when he did the work originally, been having to take this slowly. If they are looking obviously angled I'll take them back over and point this out to him and see what he says. Ive never dealt with machining stuff before, but machining them as a set would have made sense.

The head was rebuilt by a reputable head shop so as far as I know they checked the mounting area out when they did the work.
 

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I will try to see if connecting the two together once I get them off will show how off they might be. Wish I would have checked this months ago when he did the work originally, been having to take this slowly. If they are looking obviously angled I'll take them back over and point this out to him and see what he says. Ive never dealt with machining stuff before, but machining them as a set would have made sense.
if the intake manifold was not machined along with the exhaust manifold then it will always be off and never fit right because the flanges will be on different planes and angles. I would bolt the two manifolds together and take them to the machine shop and have them machine the intake to match the exhaust. Have them machined as one assembled unit straight and true. Then it should fit your engine with no problems.
 

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Discussion Starter #8
Bummed and Disgusted

I took off the manifolds, bolted them together and sure enough.....


So I talked to the guy who did it and asked him why he machined them separately and he said "Because you gave them to me separated" ...which I did:mad:

I told him that being new to auto mechanics it didnt occur to me that I would have to point out to a machinist who has a garage full of engine blocks, heads and manifolds that they need to be machined together. He said he was sorry and that if I bring him another one he will do it properly and free of charge.:eek:

So im in the market for what I hope can be just the exhaust manifold but the thicknesses would have to be close to the intake I have which from its side looks like this in thickness

 

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Good Lord! Thats waaaayy off. The angle is tooo severe to have the intake matched up or be of any use. It shouldn't have been angled to start with. Dude messed up major! I would just have that guy refund you or pay for another exhaust manifold.
I have a friend down the street from me who is parting out a 66 Nova with a 6cyl in it. still has the manifolds on it. if you've had the intake manifold already machined, then you're better off getting both manifolds together off the same engine that way they are matched. I also know where there are some at at local salvage yards here as well. PM me if interested.
Man I'm sorry this happened to you.
 

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Discussion Starter #10
Thanks Rotorbolt, you can just tell when a refund aint going to happen and this is one of those deals. Dude does this out of his garage at home and all he'll give me is a redo. Which I will not be taking him up on. Live and learn.
 

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From the first picture, it appears that the front exhaust port and likely the rear still have the non-threaded pins in place. These can be removed with a stud puller or a pair of vice grips and replaced with threaded studs matching the others. It should fix or significantly reduce the problem
 

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Discussion Starter #13
Heres an update, I purchased an exhuast manifold from a member on the site and bolted it together with the intake I already had and there was a 16th gap between the face of the ports that connect to the engine.

So I took them back to the machine shop that botched the job originally and took the guy up on his only offer which was to redo the job properly at no additional charge. I left it all with him and told him to bolt them together this time before machining it.

Got a call this evening from him and he said he was able to on the exhuast...
  • bead blast
  • remove the chopped studs that were on it
  • replaced with new studs
  • drilled out the 2 screws that had snapped off in there from the choke thermostat and tapped new threads

then he said he wasnt going to be able to machine them and suggested that I put them on the motor and then tighten the 2 manifolds together since there is enough play between the two and that should work fine. But he said that he didnt feel that bolting them togteher and machining would come out too good.

So I pick everything up tommorrow and do like he says and see what happens. If they dont fit flush then I'll take it to a shop that can get it done right. Ill take a pic tommorrow and post it once i get it on the motor.
 

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I'm glad you didn't get em machined yet. I was worried for you that things might get messed up again. He is right about the play allowance when lining the two manifolds up. I haven't put mine on yet and I bolted them together leaving them loose and as a result they shift around slightly. Before you install, try to remove the aligning studs on the front and rear of the head ( they look like they are threaded in, at least on mine. not pressed in as one would think. use good vice grips and twist counter colckwise on them ) and replace them with fully threaded studs. Like bruce said earlier in this thread. This will give you more uniform clamping force on the manifold for a better seal. I'm going to do that with mine.
Bolt your exhaust and intake manifolds snugly together but do not tighten them . leave them loose enough to move some. Bolt up the manifold assembly to the engine to get the two manifolds on the same plane as the engine facing and then tighten down the bolts holding the intake and exhaust together. Then final tighten the manifolds to the engine to the proper torque specs and sequence.
Everything should bolt up flush with no problems. Good luck.
 

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Discussion Starter #15
I'll follow yours and bruce's lead on this an try to pull those aligning pins.
Will the pin in the front be an issue to bolt on with a washer? or nut?
The one in the front I think gets covered by the power steering bracket, not sure how much of a concern that is.
 

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Discussion Starter #16
Thats Better

Bolted them on real quick and it looks like things are lining up right.







Only problem I'm seeing is that the intake manifold now has a crack at the lower part of the opening where the bolt runs through it. Guess I need to take it somewhere and have it welded up.:mad:

 

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looks good. Glad things are working out. I bet that crack happened when you tried to bolt it up with the other exhaust manifold. Welding up cast iron isn't easy. It doesn't look bad. You could probably just leave it be and everything would tighten up alright. But if you're like me, that crack will bother you till it gets fixed..
I tried pulling the aligning pins off my engine today with no luck. Those things are really in there. might want to scrap that idea. I kinda galled one of my pins up trying to get it out. Anyone have suggestions on how to get em out?
Keep us updated.
 

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Discussion Starter #18
Yeah i noticed the split before i bolted it on but I aint about to take it back to the guy again. There is a muffler guy thats gonna put on a new exhuast pipe and muffler for me so Ill ask him for the help on welding the split and see what he can do.

Glad you told me about the dowel pins being in there pretty tight.
I'll hold off unless we get a tip from someone.
 

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A Good penetrating fuild and Maybe a Little Heat will help you remove those Pins. along with a GOOD pair of Vise Grips. Also Before hand give them a good tap with a Hammer sometimes helps. That is how I remove all mine Minus the hammer. Some That I Had a REAL hard time with I gave a Quick zap with a welder .Oh and I may still have a few stock intakes but i'd have to look.
 

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Discussion Starter #20
All Installed

Got it painted up and bolted on now, now to get the rest of the engine put back together and see how/if it runs. Ill be taking it to a local muffler shop to have a new exhaust installed once its running.

 
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