what is the torque value for the head bolts? 70 lbs?
Thank you in advancer, Bob
I was told that 45-50 ft pounds was enough. and 55 to 60 was nearing the breaking point of the bolts
I normally go to 50 or 55 ft/lbs and that with good bolts and threads. Higher torque and you are more likely to strip threads.
70 Lb - ft will strip the threads on any Model T head bolt Robert.
I just installed a low head on a '14 engine that I am building. I used the Ford cylinder head bolt / spark plug wrench. I sprayed the gasket on both side with Krylon dull silver enamel and let it hang until it was just tacky.
While waiting for the gasket, I wiped down the cylinder head and the block several times with isopropyl alcohol to be certain there was no grease or oil. I installed the head with no gasket and ran all the bolts down to be sure none bottomed out. Then I backed out the bolts about 1/4"
I rotated the engine slowly to make sure the opening valves or the pistons did not cause the cylinder head to lift from contact. Then I removed the bolts, wiped everything down again with alcohol, and reinstalled the head with the gasket oriented properly, with the large water hole to the rear.
I tightened the center row of bolts first, starting with the very center bolt, and gradually tightening the outer bolts using the Ford head bolt wrench. You can see the pattern here:
The head bolts get re - tightened once after the engine is brought to operating temperature and cooled overnight.
I have used 55 in the past. I now play it safer at 50 and it works fine.
Thanks for the step-by-step Royce.
I like to torque them in order such as in the picture above. I do them to about 20 ft lbs, then go back and do in order to 30 ft lbs, then 35 ft lbs 40 ft lbs and 50 ft lbs. That way everything is evenly tightened and not warped or put a strain on anything. After you warm up torque again if you have an iron head. If aluminum, wait for it to cool off overnight to re check. Drive it around for a while and check again. Do this several times until they stay at torque overnight. Then you don't need to do it again.
I did 60 once and stripped some threads in the block. Since then, I've used 50 with no problems. Some folks here have said they used 45 with good results, so that may be enough. It's no fun to strip one.
I have pulled threads out of the block trying to do 50.
Since then, 1987, I always stop at 45 max.
I do 20 the first time around, then 35 and finally 45.
You can usually get some bolt movement doing the 3rd retorque.
Robert... Don't use a torque wrench. Just use the Ford head / Spark plug wrench. The length of the wrench allows the correct torque when tightened by an average adult male. Also, note in Royce's comments about using the silver paint. I believe I mentioned this to you when I was at your house a few weeks ago. It's the way it's been done for years.
Also, I'd advise you to replace the head bolts with newly manufactured head bolts. I have had the head off my 15 touring 3 times in 11 years. Twice, I had a head bolt snap. Fortunately I was able to just back the threads out of the block. Finally, I just replaced all the bolts. The metal seems to crystalize over the years of heating and cooling cycles.
I agree with James, never had a gasket blow using this method and it was what Ford intended.
The head on my 15 seated perfectly at 35 ft.lbs. with no leaks. It did need to be retorqued twice after running and cooling.
Royce's procedure is the proper way to go.
I set at 40 lbs get it hot run for a little bit them befor it cools the take it to 45 to 50 never had an issue