james hitchcock
Well-known member
I don't remember what is the torque setting on the manifolds.
Torque setting on manifold
- Thread starter james hitchcock
- Start date
james hitchcock
Well-known member
Thank you.
BILL WILLIAMSON
Well-known member
James,
Say, "thank you that I didn't reply!" Seems that everytime I mention torque, Loctite, or pre-load, I get folks all stirred up! Bill W.
Patrick L.
Well-known member
Like said, 35-40 ish.. They didn't torque them back in the day.. They just snugged up up evenly..
BILL WILLIAMSON
Well-known member
They were ignorant about torqueing, that was a looooong time ago. A lot of things were learned since then.
Their motto was probably: little bolt, a little tightening, medium bolt, a little more, a Big bolt, 2 GRUNTS, rear axle nut, 3 GRUNTS! Lots of things they did back then wasn't necessarily the best way. Bill W.
Their motto was probably: little bolt, a little tightening, medium bolt, a little more, a Big bolt, 2 GRUNTS, rear axle nut, 3 GRUNTS! Lots of things they did back then wasn't necessarily the best way. Bill W.
28ACoupe
Well-known member
One of the best tools I have in my box is a copy of the Pocket Ref. You can go through an entire car and not know any torque settings for anything and get all the torques correct.
BILL WILLIAMSON
Well-known member
Thanks,
I'm gonna order one, handy!
Torque is so important, first to make sure it is tight enough, and also for uniformity. Worked with a shop IDIOT once that was always BREAKING bolts & "squishing" soft gaskets_*&%$#^# I spent a whole lunch hour teaching him TIGHTENING-101! Bill W.
tbirdtbird
BANNED
Bratton's catalogue has a spec and torque table in the front, very handy. Good ol' Walt...
And the manifolds don't wanna be too tight because they are gonna move back and forth a bit from expansion/contraction of exhaust heat. If too tight, somethings gonna snap or warp.
And the manifolds don't wanna be too tight because they are gonna move back and forth a bit from expansion/contraction of exhaust heat. If too tight, somethings gonna snap or warp.
james hitchcock
Well-known member
I know this info is to be found the many Model A books, but you guys on the Barn are so dang fast with your responses and I like the fact that you've all been there and done that.
Thanks again.
peters180a/170b
Well-known member
I don't know,, never torqued them before ,,,I just start left and right side nuts of the carb. and work my way out to the two ends. Keep going over and over,, left to right 2 inner to two outer so the gasket works to the outside edge and don't bind up. never had a problem. But everyone is different.Had both manifolds milled together.
BILL WILLIAMSON
Well-known member
tbirdtbird, (sounds like an echo-echo),
Catalogs are almost like a shop manual, if read completely. Are we too lazy to read?
Shucks, we can a make a Model A run by the seat of our pants & a collection of parts catalogs! They even have PICTURES!
You just gotta' stop & think things out.
Can you imagine the questions a poor Model A parts man recieves,
and his Dear Wife wonders why he's GROUCHY?
Most modern manifolds are real tight, so they don't shrink and expand in length & shear off the studs. Datsun & Nissan "Z" cars for example.
I've been around the "Horn" 2,870 times, I aint' no rookie! Bill W. (THORN!)
jkeesey
Well-known member
Modern Chevy and ford manifolds are cracking in the centers from being too tight and not leaving room for expansion. I run A manifolds at 45ft lbs after the manifolds have been cut together and the block has been checked true. Ive done over 30 of them in the past few years and have never had a problem.
Napa Skip
Senior Member
There are other reference guides, both for specific torque values and for general torquing procedures, some of which are (or were) available gratis. Two that I obtained in 1989 when I was a mechanical engineer for the Oceanic Division of Westinghouse Electric Corporation were free from an automotive parts store across the street from our offices. Both were from Fel-Pro Incorporated of Skokie IL; the first is “Fel-Pro 263-85 Gasket Installation Manual” and the second is “Fel-Pro 486-89 Complete Cylinder Head Torque Specifications” (including torque-to-yield information, not applicable, insofar as I know, to Model A’s).
The “Gasket Installation Manual” has chapters on 'Things You Should Know About Every Gasket Installation'; as well as 'Cylinder Head Gaskets'; 'Manifold Gaskets'; 'Oil Pan Gaskets'; 'Timing Cover Gaskets'; and 'Adhesives, Sealants and Other Products Used in Sealing Gaskets'.
While I suppose Fel-Pro might have a different slant on things than other gasket manufactures, they do appear to provide a “best practices” approach to what – at least in 1985-1989 – was the industry standard for proper gasket installation, assembly closure torquing, and use of gasket sealants.
Here are some excerpts, applicable not only to this thread, but to several recent threads debating the use of not only torque wrenches but gasket sealants, RTV (sacre bleu!; Fel-Pro recommends the use of RTV for multi-part pan gasket joints), hot and cold torquing and retorquing, different approaches for cast iron and aluminum components, and…
“Check for warpage and distortion [by placing] a straightedge lengthwise on the head surface, and slide a feeler gauge between the head and the straightedge. A good rule for flatness is not more than 0.004” out-of-flatness for four-cylinder heads” both lengthwise and widthwise. The same procedure – and specification - is recommended for the block.
"If the [head or block] surface is too smooth, the gasket cannot grip the surface to give a good combustion seal. If the surface is too rough, the gasket will not confirm to the surface, causing fluid leaks. A finish of 90 to 110 micro-inches RMS [Root Mean Square] is preferred. Many head gaskets will not seal when the surface is outside this range.”
“If the head or block has been resurfaced [or] if the threads run up to the surface, chamfer and retap the hole. The threads then will not be drawn above the [head or block] surface when the bolts are tightened [which] is enough to cause gasket failure.”
“Wire brush the threads on all assembly bolts, check the bolt threads for damage and lightly lubricate the threads with engine oil before assembly. Dry…threads can decrease the bolt’s clamping force by as much as 50% [and] lead to false torque readings and possible gasket failure.”
“Older [gasket] designs, such as the steel-faced sandwich-and-perforated-core, require the cylinder head to be retorqued [since] these gaskets take a set after initial engine operation and relax to the point where retorquing is needed to restore the clamping force. Run the engine to a normal operating temperature (usually 5 to 10 minutes), shut off the engine and carefully retorque the cylinder head bolts/nuts for a second time while the engine is still hot if the engine is cast iron. If the head or block is aluminum, cool to room temperature. Follow the torque sequence to the specified amount in the torque tables. Retighten a third time after 300 to 500 miles.” [Note that nothing was mentioned, either way, about breaking torque before retorquing.]
“Some exhaust manifold gaskets have a perforated steel face on one side and a soft face on the other. The steel face is positioned toward the exhaust manifold…because the exhaust manifold expands when it is heated during operation [and] moves. Due to high heat conditions, it is important to retap and redie all threaded bolt holes, studs, and mounting bolts/nuts [to] ensure tight, balanced clamping forces on the gasket. Lubricate the thread with a good high temperature anti-seize lubricant [and] install the bolts/nuts finger tight [and] then tighten in three steps [to] ½, ¾ and full torque following the torque tables. Torquing…is begun in the center of the manifold, working outward.”
Lots of good information from people who make a living making gaskets.
The “Gasket Installation Manual” has chapters on 'Things You Should Know About Every Gasket Installation'; as well as 'Cylinder Head Gaskets'; 'Manifold Gaskets'; 'Oil Pan Gaskets'; 'Timing Cover Gaskets'; and 'Adhesives, Sealants and Other Products Used in Sealing Gaskets'.
While I suppose Fel-Pro might have a different slant on things than other gasket manufactures, they do appear to provide a “best practices” approach to what – at least in 1985-1989 – was the industry standard for proper gasket installation, assembly closure torquing, and use of gasket sealants.
Here are some excerpts, applicable not only to this thread, but to several recent threads debating the use of not only torque wrenches but gasket sealants, RTV (sacre bleu!; Fel-Pro recommends the use of RTV for multi-part pan gasket joints), hot and cold torquing and retorquing, different approaches for cast iron and aluminum components, and…
“Check for warpage and distortion [by placing] a straightedge lengthwise on the head surface, and slide a feeler gauge between the head and the straightedge. A good rule for flatness is not more than 0.004” out-of-flatness for four-cylinder heads” both lengthwise and widthwise. The same procedure – and specification - is recommended for the block.
"If the [head or block] surface is too smooth, the gasket cannot grip the surface to give a good combustion seal. If the surface is too rough, the gasket will not confirm to the surface, causing fluid leaks. A finish of 90 to 110 micro-inches RMS [Root Mean Square] is preferred. Many head gaskets will not seal when the surface is outside this range.”
“If the head or block has been resurfaced [or] if the threads run up to the surface, chamfer and retap the hole. The threads then will not be drawn above the [head or block] surface when the bolts are tightened [which] is enough to cause gasket failure.”
“Wire brush the threads on all assembly bolts, check the bolt threads for damage and lightly lubricate the threads with engine oil before assembly. Dry…threads can decrease the bolt’s clamping force by as much as 50% [and] lead to false torque readings and possible gasket failure.”
“Older [gasket] designs, such as the steel-faced sandwich-and-perforated-core, require the cylinder head to be retorqued [since] these gaskets take a set after initial engine operation and relax to the point where retorquing is needed to restore the clamping force. Run the engine to a normal operating temperature (usually 5 to 10 minutes), shut off the engine and carefully retorque the cylinder head bolts/nuts for a second time while the engine is still hot if the engine is cast iron. If the head or block is aluminum, cool to room temperature. Follow the torque sequence to the specified amount in the torque tables. Retighten a third time after 300 to 500 miles.” [Note that nothing was mentioned, either way, about breaking torque before retorquing.]
“Some exhaust manifold gaskets have a perforated steel face on one side and a soft face on the other. The steel face is positioned toward the exhaust manifold…because the exhaust manifold expands when it is heated during operation [and] moves. Due to high heat conditions, it is important to retap and redie all threaded bolt holes, studs, and mounting bolts/nuts [to] ensure tight, balanced clamping forces on the gasket. Lubricate the thread with a good high temperature anti-seize lubricant [and] install the bolts/nuts finger tight [and] then tighten in three steps [to] ½, ¾ and full torque following the torque tables. Torquing…is begun in the center of the manifold, working outward.”
Lots of good information from people who make a living making gaskets.
Last edited:
tbirdtbird
BANNED
Good stuff.
Installation manual:
http://www.frontiernet.net/~tmeyer/fpro.html
Torque Tables and the best explanation of torque-to-yield I have seen. None of this really applicable to Model A, but some of us work on lots of different engines
http://olybrake.com/pdf/fel_pro_torque_specs_guide.pdf
Glad to see the mention to re-torque cast iron stuff hot, and not cold. Some posters here are re-torquing cast iron cold, and that goes against any mechanical practice I have ever seen in > 60 yrs
Installation manual:
http://www.frontiernet.net/~tmeyer/fpro.html
Torque Tables and the best explanation of torque-to-yield I have seen. None of this really applicable to Model A, but some of us work on lots of different engines
http://olybrake.com/pdf/fel_pro_torque_specs_guide.pdf
Glad to see the mention to re-torque cast iron stuff hot, and not cold. Some posters here are re-torquing cast iron cold, and that goes against any mechanical practice I have ever seen in > 60 yrs
Mike V. Florida
Well-known member
Even the Ford service bulletins call out torque warm.
Tom Wesenberg
Well-known member
I never use a torque wrench on manifolds.
Also you must remember that because a certain stud and nut can take some amount of torque, that doesn't mean the part being clamped can take the same amount of torque. Cast iron manifold ears on a soft copper gasket might fit in here.
Also you must remember that because a certain stud and nut can take some amount of torque, that doesn't mean the part being clamped can take the same amount of torque. Cast iron manifold ears on a soft copper gasket might fit in here.