Head retorque questions

The_Josh_Bear

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So myself and another member recently have had coolant leaking from the head gaskets at the rear of the engine. I asked about doing a head retorque and got some answers on both sides, I went ahead and did it. 10k worry free miles later its leaking almost zero coolant and whatever is missing I haven't yet cared enough to trace it down.

The question I have now that I've already done it:
What sequence to you torque them with? Everyone says "the book sequence" but in the book it goes by crisscross pattern for two sets as all heads do, then it goes sequentially left to right accross the head for the last two sets. These are completely different patterns.

Second question and maybe more important: all the bolts under the valve cover are SOAKED in oil. All the bolts visible outside the valve cover are dry and rusty. How do we ensure they are all torqued equally?? Lubed threads tighten way more at the same torque as rusty dry threads.

Thanks!

Edit: I used the sequential pattern since that's how the final pattern goes, but I was pretty torn about it. And irregardless of the coolant issue, I'm really glad that I retorqued the heads. Some of the bolts were terribly easy to release.
 
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Macrobb

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I would probably use the 'spiral' pattern(the first pattern) - if you think about it, the pattern basically pushes outward from the center, trying to distribute stress evenly.
The second pattern, IMHO, is there to prevent you from 'missing' one in the pattern and having a looser-torqued spot.

As for dry vs oily ones... I don't have any idea. Sorry. I'd probably just do them all the same no matter what, to spec.
 

IDIBRONCO

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The bolts under the valve covers aren't soaked with oil all of the way down to the bottom. Unless there's a groove in the head, washer, or bolt head, the oil has no way to get past the outer part of the washer or bolt head. They are torqued to at least 80 lb-ft (6.9).
 

The_Josh_Bear

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The bolts under the valve covers aren't soaked with oil all of the way down to the bottom. Unless there's a groove in the head, washer, or bolt head, the oil has no way to get past the outer part of the washer or bolt head. They are torqued to at least 80 lb-ft (6.9).
I've literally only worked on this one IDI, so my experience is very limited but this is exactly how my entire engine was. Outside bolts dry and rusty, inside bolts oil soaked through and through. Every bolt under the covers was super slick and easy to turn(save for maybe one or two?) While the outside ones were just like you would think a bolt would be in a hot, dry, steel environment.

I know you've broken down/rebuilt many many IDI's. You're saying my experience is the exception rather than the rule?
 

Macrobb

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I've literally only worked on this one IDI, so my experience is very limited but this is exactly how my entire engine was. Outside bolts dry and rusty, inside bolts oil soaked through and through. Every bolt under the covers was super slick and easy to turn(save for maybe one or two?) While the outside ones were just like you would think a bolt would be in a hot, dry, steel environment.

I know you've broken down/rebuilt many many IDI's. You're saying my experience is the exception rather than the rule?
Mine have always been the same as you - rusty/crusty ones on the outside(next to exhaust manifolds too!), nice and oily ones on the inside.
 

renjaminfrankln

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I've literally only worked on this one IDI, so my experience is very limited but this is exactly how my entire engine was. Outside bolts dry and rusty, inside bolts oil soaked through and through. Every bolt under the covers was super slick and easy to turn(save for maybe one or two?) While the outside ones were just like you would think a bolt would be in a hot, dry, steel environment.

I know you've broken down/rebuilt many many IDI's. You're saying my experience is the exception rather than the rule?


I have the same questions. Did you remove any of the inside bolts? Were the threads soaked in oil as well? They may not be.

My thinking was that id probably hit the heads of the outside bolts with some oil and break them free before proceeding.
 

The_Josh_Bear

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I have the same questions. Did you remove any of the inside bolts? Were the threads soaked in oil as well? They may not be.

My thinking was that id probably hit the heads of the outside bolts with some oil and break them free before proceeding.
Yeah I removed a bunch of them(one at a time, in sequence!) once I felt the difference. Eventually I realized they were all like that and quit checking.
Soaked to the tip.
 

IDIBRONCO

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I know you've broken down/rebuilt many many IDI's. You're saying my experience is the exception rather than the rule?
Not really. The oil on the inside bolts probably runs down from above as you remove them. The outer bolts (especially the bottom row) get rusty because of the odd shape of the bottom of the head and the top of the block. If you look closely, there's a "V" shape where they meet when they are in the installed position. IIRC, you can actually see part of the shanks of the bolts where it is exposed. This will let external water seep down the shank and even get to the threads. This is where the rust comes from. Surface tension will hold a surprising amount of oil on the bolt heads and the washers where they are bathed in oil. Remove the head bolts one time with an impact wrench and you'll have a socket and the front of your shirt soaked with oil. Your front of impact will also have a good coat of oil even if you have one with exhaust that exits out of the handle. The places where your washers sit on the heads are machined flat. You'd lose a good deal of holding power if these spots aren't flat. There could be a groove in one of those spots for some reason, but I'd bet that there's no way it's factory.
 
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