HELP!!! Cracked Air Intake

[2B32]

-Ok, so to preface, I am not a mechanic but I'm trying to learn. As a result I am making a lot of mistakes.

Today I was switching out my carb for a Sniper EFI unit. While doing so I tried to seat the vacuum port on the intake (the line that runs from the brake booster to the port behind the carb) a little lower to gain some clearance. In doing so I cracked my intake (stupid, I know).

Realizing my intake was now garbage I pulled it, and found oil on all the intake bolts, and oil puddled under the intake. This is a project that I'm learning was jimmy-rigged a lot by the previous owners. I found liquid sealant all over the thermostat, and it looked like some sort of silicone sealant was used for the intake.

I've read a bad intake seal will allow oil to leak. Is the oil on the intake bolts, and puddled oil under the intake from the crappy gasket that was used, or am I looking at a bigger problem here?

[davepl]

Just to be totally pedantic and accurate, the valley is always full of oil, so the underside of the intake will always be covered in oil. I'm not sure if you thought that was a problem or not, but that part's OK.

Generally the bolts should be dry, but that doesn't necessarily mean oil was getting anywhere bad (like into the intake ports). But if it's been ingesting oil, you might foul plugs and use oil and so on.

Other than you having a cracked intake and needing new gaskets, I don't see any problem at all, unless I'm missing something...

[2B32]

Originally Posted by davepl

Other than you having a cracked intake and needing new gaskets, I don't see any problem at all, unless I'm missing something...

Like I said, I'm no mechanic, so I wasn't sure. Thanks for the clarification!

[HO455]

Let's see a photo of the crack maybe it can be fixed.

[custom10nut]

Are you asking about the little bit of oil that appears on the intake manifold?
If so, that's a normal issue, if you don't put thread seal on those four bolts.
The oil swaps p the threads and it pools there.
More of an annoyance than a real problem.

[Jcfcamaro]

You could have just put some really good silicone over the crack . You would be surprised how long it would have lasted.

[2B32]

Originally Posted by HO455

Let's see a photo of the crack maybe it can be fixed.

There are actually two cracks. One is very fine, the other is more pronounced.
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[HO455]

It's hard to tell from the photo, is the intake aluminum? If so then it can be TIG welded and the threads cleaned up with a tap. If it is cast iron it can be brazed or welded but it is getting harder to find people these days who can do cast iron. It may be easier to find a cheap factory manifold. If your still looking for the fitting to sit just tap the hole deeper. Pipe threads are tapered so they fit tighter the more you tighten them. That's why the hole spilt on you. If you need to have a fitting sit deeper you have to run a tap down and cut it deeper. Just don't get carried away. Do a little at a time, like one turn and check it with your fitting. Don't forget to use oil on your tap.

[midniteblues]

Sealer should be used on all the inner intake mounting bolts as only the four outer corner bolts have blind holes and can't wick oil up through the threads.

Gotta watch the length of the bolts used on the outer corners you could bottom them out and never seal the intake properly.

Also if you use too long of a bolt in a few of the other holes you can essentially lock up a push rod if they make contact.....not a good situation upon start up.

I would tighten your fitting back into the intake just a turn or two more too open up those cracks.
Then clean around the cracks real good with some brake clean.
Warm up and mix up some jb weld.warm it up real well so it flows good if its cold.

Use a small brush, wire or make a small spreader too get it into the cracks good. Then turn your fitting back out a few too close up the cracks.

Clean up excess and wait for it too dry ....use some brush on Sealer like Indian head on the fitting too reinstall it then you won't have too tighten it alot and reopen the cracks.

That's a po man's fix, intakes are cheap & plenty enough too pick up another.

[saxart]

Originally Posted by midniteblues

I would tighten your fitting back into the intake just a turn or two more too open up those cracks.
Then clean around the cracks real good with some brake clean.
Warm up and mix up some jb weld.warm it up real well so it flows good if its cold.

That's great advice, but be careful "warming up" anything that's been previously cleaned with brake clean. There are documented cases of people getting severely injured welding metal that has been previously cleaned with the stuff. This is certainly a different situation, but it's worth noting as the toxic fumes are deadly.

[James the III]

Originally Posted by saxart

That's great advice, but be careful "warming up" anything that's been previously cleaned with brake clean. There are documented cases of people getting severely injured welding metal that has been previously cleaned with the stuff. This is certainly a different situation, but it's worth noting as the toxic fumes are deadly.

True if you can even get that type brake clean.. many states you can't even buy it..

I'd not even bother..
I'd coat the fitting threads with a liberal amount of blue thread locker with the crack facing /pointing down put some thread locker liberally on the crack, and install the fitting.. the tread locker can flow into it..
only tightn hand tight.. the thread locker will hold it there..

You don't want to tightn the fitting to spread the crack as if you look the casting line is near it outside the hole/boss. You don't want the crack going farther..

leave the intake with the crack pointing down.. and walk away.. let it dry..
it'll be fine..