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Discussion Starter #1
I checked the specs in the Motors Manual at the library and it says 59 ft. lbs on the heads of a 3.8. The counter man at the parts store says he thinks that is a stop point, then turn another 90 degrees. Is there any truth in that? It doesn't seem very acurate to me. Maybe that's why these things blow head gaskets?
What's the procedure for torquing heads on a 3.8? I always go in three or four steps, but what's this '90 degree thing? I'm used to the older engines that run from about 85 to 135 ft. lbs. 59 seems odd.

Also, do I need thread sealer on any of the head bolts, if so, which ones? I can't find much info on this and hate to have to do something twice.
 

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WARNING: This engine uses "Torque To Yield Bolts". Always use new cylinder head bolts to ensure leak-tight assembly. Torque retention with used bolts can vary, which may result in coolant or compression leakage at the cylinder head mating surface.
12.Reverse procedure to install, noting the following:
a.Lightly oil all bolts except short ones.
b.Apply suitable sealer to short cylinder head bolts.
c.Using tightening sequence shown in Fig. 7, torque cylinder head attaching bolts in steps as follows:
1.50 N-m (37 ft. lbs.)
2.60 N-m (45 ft. lbs.)
3.70 N-m (52 ft. lbs.)
4.80 N-m (59 ft. lbs.)
5.Loosen bolts 2-3 turns
6.15-25 N-m (11-18 ft. lbs.)
7.Long bolts an additional 85-105° 8.Short bolts an additional 65-85°
1991 Ford Thunderbird V6-232 3.8L Copyright © 2009, ALLDATA 10.10 Page 2
13.For each valve, rotate the crankshaft until the tappet rests on the base of the camshaft lobe, install the pushrods and torque rocker arm fulcrum attaching bolts to 5 N-m (43 in.lb). 14.Once all of the rockers are in place and temporarily torqued, torque all fulcrum arm bolts to 25-35 (19-25 ft lbs). For this step the camshaft may be in any position. 15.Torque rocker arm cover bolts to 9-12 N-m (80-106 lbs.in.).
 

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Back up and punt with some new bolts.
 

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Discussion Starter #4 (Edited)
Thanks, ClintD, and Monk, Yeah, I already got new bolts. Always get new head bolts, no matter what the engine.
Question on no. 5 above: Does that mean, after torquing to 59 ft. lbs., I back off 2 to 3 turns? or 2/3 turn?
And no. 6: Does that mean to tighten them back to between 11 and 18 lbs.? or first to 11, then to 18? Then after that I turn each bolt the number of degrees shown? Just want to be sure I am reading this right. Hate to screw something up or have to start over.
Kinda goofy torquing. No wonder they blow head gaskets. But I can follow the rules, so long as I know what the rules are.

"The wise man doesn't know everything, he just knows where to find out what he needs to know".
 

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Thanks, ClintD, and Monk, Yeah, I already got new bolts. Always get new head bolts, no matter what the engine.
Question on no. 5 above: Does that mean, after torquing to 59 ft. lbs., I back off 2 to 3 turns? or 2/3 turn?
And no. 6: Does that mean to tighten them back to between 11 and 18 lbs.? or first to 11, then to 18? Then after that I turn each bolt the number of degrees shown? Just want to be sure I am reading this right. Hate to screw something up or have to start over.
Kinda goofy torquing. No wonder they blow head gaskets. But I can follow the rules, so long as I know what the rules are.

"The wise man doesn't know everything, he just knows where to find out what he needs to know".
loosen them all, the retighten them to 18ft/lb.
then a additional 90degrees.

It gives you a range 90-105 so if you go over 90 its not to crucial.
 
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