Ah yes...intake bolts

[opus]

Reading all the fun issues regarding intake bolts, I thought I would take a try at it. I got about 3 of them to break loose. The others just want to flex. I didnt try too hard though.

 

Do you think an impact wrench would have less negative effects than brute strength? I'd love to get these off without breaking them. :/

[thealleyboy]

In a situation like this, I have found leverage to be the safest method.

I have several sections of pipe that I slip over the ratchet handle. The longer the handle = the more leverage. With the longer ones, you can increase torque more gradually, and lessen your chances of snappnig the bolt.

 

I'll also reccommend replacing the old bolts when re-assembling the intake manifold. They will distort and weaken every time they are used. A good rule of thumb when bolting into aluminum: the thinner the bolt, the greater liklihood that it should be replaced.

good luck, John

[daeron]

In a situation like this, I have found leverage to be the safest method.

I have several sections of pipe that I slip over the ratchet handle. The longer the handle = the more leverage. With the longer ones, you can increase torque more gradually, and lessen your chances of snappnig the bolt.

 

I'll also reccommend replacing the old bolts when re-assembling the intake manifold. They will distort and weaken every time they are used. A good rule of thumb when bolting into aluminum: the thinner the bolt, the greater liklihood that it should be replaced.

good luck, John

 

+1. Also, try to find yourself a can of Sea Foam Deep Creep, and spray it on there, and let it sit for a few hours, or a day. Spray more than once. The stuff is a bit expensive but you do NOT need much; it makes PB look like Liquid Wrench.

 

Another point; While you are using this massive leverage to try to break these bolts loose, leave one hand on top of the bolt/socket/ratchet to make sure the socket stays flat on the bolt head. If you don't, it CAN slip off rather easily. Overzealous and impatient use of a cheater bar has rounded many a bolt and nut.....

[opus]

I'm surprised no one has thought of an impact wrench, on low, in bursts.

[4x4_Welder]

It breaks them.

Try applying about 30ft/lbs of torque(average pull on long 10mm wrench) and tap the intake with a hammer.

The only way I have gotten the bolts out without breaking is to loosen them with the engine warm, almost at operating temperature.

 

[Hondasucks]

And then when you get them out, replace them with stainless steel, I did that on my Turbowagon for the two long ones, and when I took the intake back off like 2 years later, they spun right out.I've had decent luck turning the bolt out like, 1/2 turn and spraying some good penetrating oil down under the head of the bolt (JB 80, P'Blaster) and then rocking the bolt 1/4 back, 1/2 turn forward until it starts to spin freely.

[Corolla Frenzy]

I used a 3/8 impact on the inside ones. What a pain! Way crusty, too. Maybe I should consider replacing them as mentioned instead of reusing haha :cool:

[idosubaru]

try to get the bolt to back off a little bit, at least enough to squirt penetrating oil down the shaft. probably won't help much as the corrossion is typically deep, but if you get any room under the head you can get some down there.

 

if you get it to break loose at all, then alternate tightening and loosening in small bits and work your way. also putting upwards pressure from under the head of the bolt as you're loosening helps as well, but this is only possible if it comes up a little bit.

 

i've never done the loosen when engine is warm trick, sounds good.

[Gloyale]

I put a dab of rtv actually in the intake bolt hole before i put the manifold on, and another tiny dab on the bolt tip. This seals the bottom of the threads where they extend into the coolant passages in the head. Same way on big Block chevy Headgasket bolt. Also lubes the threads(even torque) and acts as a weak sort of locktite too.

 

Stainless bolts sounds like a good idea too, but I've always just used high grade hardened bolts. And just like every other bolt hole in these engines, I run a bottoming tap through to clean up the threads before reassembly.

[opus]

Woohooo...they all came out!!

 

What do I torque these at when I put it together?

[DaveT]

Stainless bolts sounds like a good idea too, but I've always just used high grade hardened bolts.

 

I'd be careful with stainless. The corrosion reaction between stainless and aluminum is worse than rust. It is very hard white stuff. I discovered it when modifying my aluminum & stainless roof rack.

 

Grade 8 with anti-siese solves the problem.

 

+1 for hot engine loosening stubborn & sensitive bolts.

 

The problem with impact wrenches is you can't set / control the force fine enough. If there was a way to reliablely limit the tourque below the breaking strength of the bolt, it would probably work well. I freed up some very stuck brake adjusters with one of those little air powered hammers once, set very low.

[Corolla Frenzy]

eek so my 3/8 impact was prolly not a good idea?

 

It's very odd how much corrosion crap came out when just poking the bolt through. It got tight enough where I needed a rachet.

Sounds like this is normal? Why would any car company put metallic unprotected bolts in constant contact with h2o?

[DaveT]

eek so my 3/8 impact was prolly not a good idea?

 

Probably not. The bolts are not supposed to be in contact with water. The gasket should keep them away from the coolant. But nothing's perfect, and humidity from the air could work it's way in also. Some are pretty rusted, some not so bad.

 

The best luck I've had is soaking with Aero-kroil / WD-40 / PB blaster / etc. (insert your favorite here). Then gently turning the bolt. Alternating CCW and CW. Add more penitrant. More alternating CCW / CW.

 

After you break a few bolts, you have a good feel for how hard to push it.

 

Oh yeah, they don't put anti siese on them because that would cost more, and typical owners wouldn't ever deal with the problem.

[daeron]

I like to use copper anti seize in between the steel bolt and the aluminum thread. A bench grinder with a wire wheel is always good for cleaning the threads of the bolts, then run the dry cleaned bolt down the thread without the manifold on to clean out the thread, then wipe the bolt off and apply the copper Nev-R-Seez.

[Gloyale]

Probably not. The bolts are not supposed to be in contact with water. The gasket should keep them away from the coolant.

 

Not really, because the bolt holes are open at the bottom. They go straight through into the coolant passage(at least the long *inner* ones) The gasket can't do anything about that. Water sneaks up past the threads, and into in the intake the hole the bolt goes through. That's why those long bolts are crusty up to the top. A dab of RTV on the threads of the bolt will keep coolant from traveling up the bolt and into that bolt hole. The bottom few threads will still contact water, but the water won't be able to get all the way up the bolt, which is what causes all the problems.

[DaveT]

Not really, because the bolt holes are open at the bottom. They go straight through into the coolant passage

 

Hmmm, on the spare head I just looked at, the 2 inner ones intersect 2 of the head bolts. If they are connected to the coolant, I can't see where. There is evidence of water / coolant crud in the head bolt holes also. Maybe it was getting past the headgasket?

[4x4_Welder]

I have found that a teflon grease works great for sealing and keeping the bolts from seizing. I use Magnalube-G

http://www.magnalube.com/ not only because it has a cool name, but because it works very well. Works great on exhaust bolts too!

[Gloyale]

Hmmm, on the spare head I just looked at, the 2 inner ones intersect 2 of the head bolts. If they are connected to the coolant, I can't see where. There is evidence of water / coolant crud in the head bolt holes also. Maybe it was getting past the headgasket?

 

Yeah, I guess it's the Dual port heads that have the holes opening directly into the water jacket. I'm not sure, but I think some of the head bolts may extend into the water jacket, allowing coolant to travel up in the same fashion.