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Discussion Starter #1
So the guy i bought my car off of used too long of bolts on the two outer exhaust manifold holes on the driver side, so the holes are stripped causing an exhaust leak that cant be fixed, so im going to use helicoils. My guestion is which size kit should i use? There's a couple different kits on summit but i'm not sure which one to use and any help would be gratefully appreciated.

Thnx

Chris
 

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Discussion Starter #4
Yup it's 3/8-16in. I was a little confused cuz summit has the size as 3/8 -16 RH and kept thinking "wt* does 3/8 negative 16 RH mean?" Lol

Im just gonna take it to a machine shop and have them do it.
Hopefully its not too expensive.

Thnx for the info

Chris
 

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RH Right hand thread.

You do not need to order this from Summit, your local parts store will stock this item. http://www.summitracing.com/parts/HLL-5521-6/

Yes, 3/8-16 RH thread, you will need to also purchase a 25/64 drill bit, get a quality drill bit.

Al
 

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Yup it's 3/8-16in. I was a little confused cuz summit has the size as 3/8 -16 RH and kept thinking "wt* does 3/8 negative 16 RH mean?" Lol

Im just gonna take it to a machine shop and have them do it.
Hopefully its not too expensive.

Thnx for the info

Chris
3/8's is the bolt size the 16 is the amount of threads per inch so 3/8-16 is national coarse. there are also fine thread bolts, using 3/8's as an example the size would be 3/8-24 which is national fine threads
You should be able to do this yourself the only hard part is drilling the hole straight and that's not to hard as you already have a pilot hole and the helicoil bit is bigger
 

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personally i'd recommend taking it to a shop and pay them to do it or buy another manifold.

if the hole is buggered up too much and the 25/64 drill doesn't clean it up then when tapped it won't be right and the helicoil when installed won't be tensioned correctly... the stud will then fit loose in the hole... seen a lot of guys bugger up manifolds drilling off center, drilling half through a broken bolt the other half through the casting. drilling it crooked...

if the shop looks at it and says it's repairable then when you pick it up you're guaranteed it's right. if it's unrepairable or not worth repairing they'll tell you and then you can just get a different unit... which might very well be the cheapest way out anyways.

just my 2 pennies...
 

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personally i'd recommend taking it to a shop and pay them to do it or buy another manifold.
It's in the head.


If you do use the helicoil just go a good extra thread below the surface so it doesn't want to pull out later.
 

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You can use the manifold as a guide for the bit, but you might have to fabricate some kind of bushing if the hole in the manifold is too large.
If the hole is too small you can drill it out first.
When I did this, I used a very long bit so I could come in from the wheelwell, your car may be different.
If the hole is wallowed out too much for a helicoil repair, there are threaded inserts that might save the head, but tough to do correctly in the car.
I have also found that the high temp silcone works pretty well without a gasket, so, you might be able to run it with the bolt out, if the manifold is pretty straight.

HTH,

Jeff
 

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Discussion Starter #10
Thanks for the info guys, since im severely prone to breaking/screwing up things, i think i'll leave it to a professional for the install. That way if he messes it up i get a new head! :devil: and like FLYER said, it will be either guaranteed fixed or they will let me know if it cant be fixed.

Hot66, do you think if i put high temp silicone around where it is leaking, it will stop it?

Thanks again

Chris
 

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Discussion Starter #11 (Edited)
So besides the exhaust leak my car was running PERFECT. I was so happy and had no worries that it would make the 2 hr drive to san bruno for my army drill on the 8th.

Yesterday i went and got the helicoils put in and now MY ENGINE IS HAVING A MELTDOWN!!

First as i was driving home, i lost spark completely, pulled a wire and was getting super weak spark. Took the ign coil cover off and the holes in the cap for the bolts that hold the coil and its grounds were stripped, giving me weak ground. Walked to autozone, bought new cap, rotor, and coil. Installed, it started and i was able to get it home but everytime i had to stop at a light i had to put it in park and keep it revved up because it wanted to die at idle.

I noticed gas leaking from my electric choke linkage and backfire coming from the carb and at one point gas was pooring in my carb when i turned off the car. I put new plugs in, the old plugs were all black on the right bank (helicoil side) and my car smokes like crazy. I tried to tune the carb with a vac gauge and vac would not drop or rise when i tried to tune it, so right now the mixture screws are at 1.5 turns counterclock wise and the smoking has stopped but its hard to start. Timing is 36.

At this point the smoking has stopped, its hard to start, and now i hear a ticking, like a lifter is sticking. What happened?!?! It was running so perfect before the helicoils and now its a complete mess!

Please help!

Chris
 

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Sorry I missed your earlier question.
Today, I would say your carb is flooding, probably from trash getting into the needle and seat.
This may have caused enough raw gas to wash down the cylinder walls and into the crankcase.
You should immediately check the dipstick to see if it smells like gas and if the oil is really thinned out, and change the oil and filter if so.
This could lead to the ticking sound and the blue smoke, since the oil with the gas in it is thinner and burns off easily.
You may need to add a fuel filter in front of the carb to keep the needle and seat clear in the future. An old fuel system can have a lot of trash in it.
Oh yeah, double check your firing order and plug wires again, to make sure your not crossed up there, too, I bet they had them off to do the helicoils.
Good luck and let us know how it goes.

Jeff
 

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Discussion Starter #13 (Edited)
Sorry I missed your earlier question.
Today, I would say your carb is flooding, probably from trash getting into the needle and seat.
This may have caused enough raw gas to wash down the cylinder walls and into the crankcase.
You should immediately check the dipstick to see if it smells like gas and if the oil is really thinned out, and change the oil and filter if so.
This could lead to the ticking sound and the blue smoke, since the oil with the gas in it is thinner and burns off easily.
You may need to add a fuel filter in front of the carb to keep the needle and seat clear in the future. An old fuel system can have a lot of trash in it.
Oh yeah, double check your firing order and plug wires again, to make sure your not crossed up there, too, I bet they had them off to do the helicoils.
Good luck and let us know how it goes.

Jeff
Your absolutely right, my dipstick reeks of fuel! I check my wire placement atleast 2 times a day, just hoping that's it. But im not that lucky. Lol



All that gold is fuel, which has been there ever since i bought it and only now since i have been having these problems, have i noticed fuel leaking off the choke linkage, which is probably coming from the float seal above it. This is a 750 carb (edelbrock 1411).

Upon doing some research i found an article that talks about common problems blamed on carbs and this is what i found.

Problem: My Throttle Plates Are Almost Completely Closed, But My Motor Idles Too High. Solution: In this scenario, air is entering the motor from a source other than the carburetor, which suggests a leak at the intake manifold. "Overtightening the manifold bolts, gasket misalignment, and using the wrong gaskets can all cause leaks," says Brown. "It's a very common problem that results in low manifold vacuum, a high idle speed, and lots of fumes and hydrocarbons out the tailpipe." Murphy estimates that 60 percent of all the cars he works on have a manifold leak. "A small leak may only kill one cylinder, which makes the motor idle rough, but everything smoothes out as the increase in rpm and air velocity moves enough fuel to cover it up,"

At this point, this is exactly what my nova is doing, almost nonexistent vac, super high idle 1200 no matter where i set the rpm screw, and lots of strong fumes and smoke out the exhaust. Again, like the fuel leaking from the float, i noticed and intake leak do to some oil seeping out from it, but my car was running perfect so i held off ripping the manifold off because ive never done it before.

Now it seems, i have fixed my exhaust leak and now my nova has found the float and manifold leak and attacked that, making me pay for my procrastination. Lol

Looks like i gotta do a carb rebuild, which ive never done and looks really intimidating.

And change the intake manifold gasket, which ive never done and looks really intimidating. Lol

Guess there's a first time for everything...

Ive already started my shopping list for all the parts ill need for this, im just not sure which carb gasket to get.

There are two carb gaskets on summit and edelbrocks instructions are confusing... which do you guys recommend using?

http://m.summitracing.com/parts/edl-9266

http://m.summitracing.com/parts/edl-2696

I have this manifold

http://m.summitracing.com/parts/edl-2101

And this carb

http://m.summitracing.com/parts/edl-1411

Thnx

Chris
 

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Discussion Starter #14
So everythings off and now im just waiting for parts to arrive

Any suggestions on what to clean my intake with? I have carb cleaner and was just gonna scrub it down with that. I was gonna bathe it in lacquer thinner but it has teflon tape and a gasket on the egr blocker so that's a no go. I was gonna bathe the carb in that when i take all the gaskets off, is that ok?

Thank god all the rods are straight, i think i woulda cried if one was bent. Lol

What should i put in the valley when i scrap off all the gasket and stuff? I was gonna put a clean rag there but im not sure it would catch everything.

Apparently the previous owner thought it was a good idea to use every bolt in the world BESIDES a $10no set of manifold bolts... :slap:


So far, so good, just need some suggestions from the ever knowledgeable ppl on this awesome site. :yes:

Chris
 

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So everythings off and now im just waiting for parts to arrive

Any suggestions on what to clean my intake with? I have carb cleaner and was just gonna scrub it down with that. I was gonna bathe it in lacquer thinner but it has teflon tape and a gasket on the egr blocker so that's a no go. I was gonna bathe the carb in that when i take all the gaskets off, is that ok?

Thank god all the rods are straight, i think i woulda cried if one was bent. Lol

What should i put in the valley when i scrap off all the gasket and stuff? I was gonna put a clean rag there but im not sure it would catch everything.

Apparently the previous owner thought it was a good idea to use every bolt in the world BESIDES a $10no set of manifold bolts... :slap:


So far, so good, just need some suggestions from the ever knowledgeable ppl on this awesome site. :yes:

Chris
Get a pack of new single edge razor blades for gasket and rtv removal. Carb cleaner for the carb.:D nice clean rag for the lifter valley will collect most,I use shop vac after for small pieces if any. Scotch brite pads work well for the aluminum intakes. I use red on the gasket surfaces and blue for general cleaning of the top side with brake cleaner.
I find it to be easier to drop the intake down with the valve covers off.
Good luck.
 

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Discussion Starter #16
Thnx for the advice sevenzeronova, you've definitly helped out the most, if you're ever in the CA central valley let me know, beers on me. :prost:

Only other guestion i have at this point pertains to the 4coil center intake manifold bolts. I bought the edelbrock bolts which have smaller longer heads, so im hoping i wont have the same problem. When removing the old ones, i could barely even fit a wrench in there to get them off so im worried i wont be able to fit my 3/8 drive torque wrench in to torque them. Does anyone have a trick for this?

I assume the previous owner had the same problem cuz they were loose.

Thnx

Chris
 

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I use the smaller headed bolts for the intake also. I have never torqued an intake or exhaust with a torque wrench and never stripped any in my 35+ years working on these cars and bikes.
 
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