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By 55charliebird - 4 Years Ago
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After run-in to get engine hot, can you retorque the head bolts to 75 ft. lbs without removing the rocker arms? (the ends of the rocker arm shafts are interfering with head bolts ). If you have to remove the rocker arms do you have to re adjust the valve lash again? Thanks as always..
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By Hoosier Hurricane - 4 Years Ago
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You should re-adjust the valves anyway, re-torqueing the heads will move the heads closer to the block, affecting your initial adjustment. The change will be very small however.
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By NoShortcuts - 4 Years Ago
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55charliebird. John's info is what you want to do. Re-torque the heads using the recommended bolt order sequence and check the valve lash setting after the engine is at operating temperature. I usually take the rocker arm shafts off to torque the head bolts. There is a tool that permits leaving the rocke rarm shafts in place to accomplish the re-torquing operation. I think it looks like this . . .
Click the link below to see an adapter previously listed on eBay that looks about like what I recall is used
https://www.ebay.com/itm/122152420669?ul_noapp=true
Hope this helps! 
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By Tedster - 4 Years Ago
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I think we should define our terms. I'd be interested in Ted's opinion and any others, on what they consider a "re-torque".
When I was in the .mil everything needed "retorques" until such time the fastener was shown to be stabilized. Probably more correctly described as a torque check, in that, the fastener was not loosened and "re-torqued" per se, simply checked for proper torque in the tightening direction. There is some difference of opinion on this with head bolts, and gasket manufacturers worked to obviate the need.
Anyhoo, the rocker shafts themselves are torqued at only 12-15 ft/lbs, but they too, will tend to need a check after a heat cycle or two. Crows feet or deep well are very useful here for some of them. Or those with a calibrated elbow just be sure to snug them up. It will affect valve lash, if only slightly.
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By Ted - 4 Years Ago
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My opinion regarding cylinder head bolt retorqing was asked for so here are my thoughts on the subject. With the original steel shim head gaskets and grade six or less head bolts, a re-torque of the head bolts was a necessity after the engine had gone through some heat cycles. I blame the grade four, five, and six head bolts for part of why that had to take place. Steel shim head gaskets by themselves are the other part of the problem and even with grade eight head bolts, can be problematic.
With the current crop of composition head gaskets and also using grade eight head bolts, I do not re-torque the cylinder head bolts after the initial engine assembly. Zero head gasket issues on the Ford Y using the Best Gasket head gaskets but I have had issues with the Fel-Pro (Perma-torque) head gaskets with water seepage at the lower edge of the head gaskets. Thirty plus years of not doing a re-torque of the head bolts on any engine has me reasonably comfortable with not making for extra work where it’s not required. I do go to the extra effort in insuring that the head bolts are brought up in a stepped tightening sequence while also doing due diligence in maintaining an outward spiral pattern when tightening the bolts. Using the appropriate lube on the bolts while also insuring that the torque wrench is accurate also helps.
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By Joe-JDC - 4 Years Ago
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When I was getting my Automotive Degree, I was taught if you wanted to re-torque the heads after engine break-in is finished, you only loosen one bolt at the time in proper sequence, and then snug it back so that you can do a single pull to torque value without stopping the pull on the torque wrench. If you think about that, the other bolts are supposed to be torqued, and the one you loosen should not affect the head as a whole, and re-torqueing in a single complete pull makes sense. You don't have to torque in steps on a single bolt. It is sort of like doing a final pull in sequence to verify torque value has been satisfied. Remember, the initial torque sequence should be done in steps to keep from cracking the head, or deforming the head gasket unevenly. I do think it is not a bad idea to re-torque aluminum heads after a few heat cycles because the aluminum will deform at the bead around the bore and lose a small amount of tension. Joe-JDC
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By Lord Gaga - 4 Years Ago
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So the proper procedure is to loosen the bolt or nut first??
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By Joe-JDC - 4 Years Ago
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When tightening a bolt with nut, hold the bolt still and tighten the nut. Loosening is same procedure, hold the bolt still, unscrew the nut. If you allow the bolt to turn it will score the shank, and cause a possible stress riser. Washers have a flat side and a rounded side from the stamping process. The flat side should always be placed against the object being secured, and the rounded side under the nut. A bevel in the washer hole should be against the bolt head. There is a lot more to this, but this is just a quick answer. I was a Master Instructor in the USAF teaching Aircraft Maintenance on F-4s, F-15s, T-33s, worked civil service on B-52s, and had to teach proper use of hand tools as a basic step in becoming a certified Aircraft Crew Chief. Joe-JDC
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By Lord Gaga - 4 Years Ago
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Sorry, I should have been more clear. I meant specifically head bolts or nuts on head studs.
Loosen first?
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By Joe-JDC - 4 Years Ago
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Same answer as above. Loosen one head bolt/nut at a time, snug it and then torque in one full pull to torque value. This is for re-torqueing them. Use original sequence. Joe-JDC
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By DryLakesRacer - 4 Years Ago
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I agree with Ted especially the use of the Best Company’s head gaskets. I run 14-1 and 13-1 racing engines and they are the only ones that have used that never failed. I also use 1/2” studs in one engine torqued to 100 psi in the fine threads and 7/16” on the other torqued to 75psi. None are re-torqued.
Our typical 8 to 9-1 engines do not see the stresses of higher compression or competition where definitely more care is taken.
Joe-JDC definitely has more knowledge on fasteners than I will ever have and military specs are there for a reason. I would trust his information. Following the manufactures recommended procedures are also very important for longevity. If the head gaskets call for a re-torque I would follow what Joe has outlined. JD
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By 55charliebird - 4 Years Ago
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JOE, ONE MORE QUESTION FOR YOU. TO MAKE EACH HEAD BOLT ACCESSABLE FOR RETORQUE, DO I HAVE TO REMOVE VALVE ROCKER ASSEMBLY AND ALSO REMOVE EXHAUST MANIFOLD TO GET AT ALL 10 HEAD BOLTS? ALSO I WILL FOLLOW YOUR PROCEDURE TO BACK OFF EACH HEAD BOLT ONE AT A TIME AND RETORQUE THEM TO 75 FT LBS USING THE PROPER SEQUENCE AND ONE PULL METHOD. AM I CORRECT ON ALL POINTS?
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By Joe-JDC - 4 Years Ago
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First, let me say there is the shop way, and there is the normal way to re-torque these bolts. The shop way is to use a "crowfoot" socket with the rocker assemblies in place. Quick and "good enough". Then there is the "double check myself" so I only have to do this once, way. If you feel you need to re-torque the head bolts, then yes it would be much easier to remove the rocker assemblies and exhaust manifold to gain access to the bolts. However, the exhaust tins have slots in them to allow a socket to reach the lower head bolts with an extension. If you need to use a swivel to reach a bolt, then remove the exhaust manifold. Swivels will not typically give you a correct torque reading because of flexing/bending. Extensions should be kept to a minimum if you use them on a torque wrench. They change the value as well if you don't keep them perfectly straight on the bolt head. Most of Ford's manuals say to add 5# torque to a rebuild on head bolts. If the threads were chased prior to assembly, and oil was used, I would use the original torque value on the re-torque.
Check the valve lash, it should not have changed much if any. Joe-JDC
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