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.
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.
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.
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.
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.
There are 2 length bolts and M6 sounds about right. They're a bit smaller than
(They do break easily if slightly overtorqued). They always seemed wimpy to
this may have been intentional to prevent overtorquing of the aluminum intake
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
torque being even among all of the bolts. A bit less or a bit more, within
good as long as they are all the same.
I see two steps at 18 and 22 "N-m" (Newton-Metres). That's 13 and 16 ft.lbs
according to Autozone's page...
and 13.28 / 16.23 according to...
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
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.
Yes, use the Haynes as kindling. It is well suited for that as they burn hot
too awfully fast.
Where are you in NE Ohio? I'm in Amherst, about 35 miles west of Cleveland. We
You must be a better man than me. If 3.8 head gaskets had been on my agenda the
couple of weeks, it would have had to wait! We just now got up into the 2 digit
That's a miserable job at 70 degrees. I hope you have heat and good lighting
in your garage.
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
Well Chip, at least you won't have to look elsewhere for something new ;). I'm
you got it done.
I was in your neck of the woods just today feeding one of my other addictions.
went to an antique radio auction in Burbank.
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
Land O'Lakes Fred
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
the jury is still out on how legal that is. (I have a full original set through
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
aren't having a field day.
Chip, take septicman up on his offer, or better yet check Ebay for the paper
for your car. There's nothing better than the original service literature when
on your own car. Helm and Chilton are full of mistakes and don't cover anything
the very basics, and then not reliably.
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.
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