snapped lower intake bolt on 3.8L v-6

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I replaced the head gaskets on a 96 Thunderbird with a 3.6L engine. I ran into a problem when I was re-installing the aluminum lower intake to the
aluminum heads. The little bolts have a torque rating of 22 ft lbs max, in three steps. I was more than apprehensive about putting that much torque on them. The intake gasket is like none that I have seen, it is about .06" plastic with silicone rubber sealing lines. I followed the procedure in the haynes manual that says tighten to 5 (in the order specified) then 15 followed by 22 (or something like that, not recalling the exact numbers). Anyway, on the second bolt, it snapped before I even got to at about 200 in.lbs. I don't quite believe the 22 ft.lbs. of torque. Can an experienced Ford mechanic tell me about these bolts and how to put them in without breaking them? I was able to grind a slot in the remains of the bolt an remove it with a screwdriver. I had to replace all of the head bolts as per the instructions, I'm thinking that the lower intake bolts should have been replaced as well but it didn't say anything about that. Now they will have to be replaced, I dont trust any of the rest of them.
Thank You for your attention and time.
Chip.
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Describe the torque wrench you used.
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The first thing you need to figure out is whether you're working on a 3.8 or a 4.6. Since you are doing head gaskets I'll assume it is the 3.8 in which case the max torque on the lower intake bolts is only 106 inch/lbs.
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I'm quite sure that it's a 3.8 -
In that case, the Haynes manuak is completely wrong. It seemed wrong anyway. Where;s a good source for the proper torques specifications? I want to make sure there are no other 'mistakes'. The torque wrence has a dial on the handle and it 'clicks' when the proper torque is reached.
Thanks,
Chip
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You can buy a helm manual. They are OEM approved... Search Helm in google. You cant miss it.

Buy a needle and pointer type torque wrench, and have it calibrated regularly, like once a year depending on how much you use it. Most techs that I know get their stuff calibrated once a year.
Ford Tech
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If memory serves me correctly that's an M6X1 bolt..usually 8-12 N-M torques spec....
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The proper torque would depend on the property class A 4.8 M6 bolt shouldn't be torqued past 6.2 N-m, the proof load would be achieved at around 8.2 N-m. An 8.8 M6 bolt should be torqued to 9 to 11.3 N-m. The proof load is achieved at around 16 N-m. Higher grade M6 Bolts (12.9) could have a proper torque as high as 16.3 N-m.
I looked at the Ford DVD and the bolt size was not given, but they looked to be bigger than an M6 - but it was only a drawing.
Ed
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If it's the intake version I'm thinking of there are M6 bols of two lenghts. I see another poster has looked it up before I had a chance to...
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Rick wrote:

There are 2 length bolts and M6 sounds about right. They're a bit smaller than 1/4". (They do break easily if slightly overtorqued). They always seemed wimpy to me, but this may have been intentional to prevent overtorquing of the aluminum intake onto the aluminum head. Better to break a bolt than to damage a head or intake manifold. Aluminum parts don't need to be attached together with Grade 5 (~12.9) bolts. 10 N-m should work for a 3.8 intake. The actual torque isn't as important as the torque being even among all of the bolts. A bit less or a bit more, within reason, is good as long as they are all the same.
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"Chip" wrote

I see two steps at 18 and 22 "N-m" (Newton-Metres). That's 13 and 16 ft.lbs according to Autozone's page... http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/14/d3/5d/0900823d8014d35d.jsp
and 13.28 / 16.23 according to... http://www.convert-me.com/en/convert/torque
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http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/14/d3/5d/0900823d8014d35d.jsp
Correct me if I am wrong, but doesnt Autozone use Hayne's manuals for their website??? I think they do, thats all they sell in the store.. But you wont catch me shoppin there, unless I cant get it elsewhere.. LOL
Ford Tech
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Well, since Autozone owns Alldata, I'm pretty sure that it's Alldata.
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http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/14/d3/5d/0900823d8014d35d.jsp
The end of the story (almost)... I did get more bolts and torqued them to 106 in.lbs. No problems. Just got in from the garage and it's almost complete. Thanks for all of the help and advice, going to have a fire using Haynes manuals for fuel. It's cold around here in NE Ohio this week.
Chip
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Chip wrote:

Chip, Yes, use the Haynes as kindling. It is well suited for that as they burn hot and not too awfully fast. Where are you in NE Ohio? I'm in Amherst, about 35 miles west of Cleveland. We may be neighbors. You must be a better man than me. If 3.8 head gaskets had been on my agenda the past couple of weeks, it would have had to wait! We just now got up into the 2 digit temps. That's a miserable job at 70 degrees. I hope you have heat and good lighting available in your garage.
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"Tom Adkins"

It's done Tom. I'm in Medina County and you know how cold it was. I put it in dad's garage and kept the torpedo heater going until it got toasty warm, took about 12 total hours to remove and a little more to clean everything up and put it back together after the heads came back with a valve job. Replaced the thermostat and everything seems to be back to normal, two weeks elapsed. I don't quire remember what my wife looks like anymore, so that will make things more interesting since I'll be living with a stranger for a while.
Chip
-
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Chip wrote:

Well Chip, at least you won't have to look elsewhere for something new ;). I'm glad you got it done. I was in your neck of the woods just today feeding one of my other addictions. I went to an antique radio auction in Burbank.
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Chip wrote:

From the Ford manual:
Tighten in two steps:
5 N-m (45 lb-in).
8-12 N-m (71-106 lb-in).
106 lb-in is a lot less than 22 ft. lbs., it's just under 9.
Rob
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Chip,
The first thing that I would do is never again in a billion years ever, ever, ever use a Haynes or Chilton manual, as they are worthless, misleading junk writtin by absolute morons who are clueless about the real nuts and bolts end of auto mechanics--I have a collection of authentic, totally complete Ford service manuals on CD. If you would like one for 96, I'll burn one and send it to you for free.
Land O'Lakes Fred
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snipped-for-privacy@peoplepc.com wrote:

C'mon Fred. don't sugar coat it. Tell us how you REALLY feel about Haynes and Chitlin's. ;) (I wouldn't hit a dog in the A** with either manual).
-I have a

Don't advertise that TOO freely. The CD\DVD versions are available for download but the jury is still out on how legal that is. (I have a full original set through '04 and share them when needs be) Copies are also prominently available on Ebay for pennies. I'm still wondering (amazed!!) why the Copyright lawyers from Ford or Helm aren't having a field day.
Chip, take septicman up on his offer, or better yet check Ebay for the paper manuals for your car. There's nothing better than the original service literature when working on your own car. Helm and Chilton are full of mistakes and don't cover anything but the very basics, and then not reliably.
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Ok according to PTS websites online WSM, the correct torque is:
1st turn- 44 in.lb. or (5Nm) 2nd go round- 71-106 in lbs. or (8-12Nm)
The book you have is wrong or you were looking at the wrong bolt torque.
Ford Tech
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