# head torque



## AL- (Oct 27, 2014)

I just loosened up all the head bolts on my B&S 4HP Bobcat. I used my torque wrench and it only took about 25 ft lbs per bolt. My repair manual calls for a re torque of 165 ft . This seems like a big difference? 
Although I loosened all of them I will only be needing to remove 3 as I am cleaning and painting the 2 rusted metal shields. Can I use the same head gasket as I am not disturbing other than loosening the bolts? 
While I've got this close to removing the head would it be a good time to actually take the head off to clean the carbon, etc. with the valves or should do this later? 
The thing is I don't know what shape the motors in, so far all I've done is pour gas in SP hole and fired it up. I've cleaned the gas tank and carburetor and am waiting for new parts , diaphragm and gaskets. I have also ordered a head gasket in case I needed it.


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## RAYAR (Mar 7, 2015)

I didn't look it up but 165 ft. lb. seems kind of high to me for a small engine. ???


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## ELaw (Feb 4, 2015)

Are you sure you're not confusing inch-pounds with foot-pounds?

I don't have a Briggs manual, but the Tecumseh manual spec for head bolt torque says 200 inch-pounds or 16.5 foot-pounds. And those are the same size bolts in a pretty much identical application.


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## Ray 1962 10ML60 (Oct 14, 2011)

Al, as others stated its got to be 165 inch pounds. The lug nuts on the wheels of my trailer are only torqued to 95 foot pounds and that goes down the highway. At 165 foot pounds you would be snapping bolts for sure. And I would just pull the rest at this point and put on the new head gasket so you can evenly torque the bolts back in when your done painting.


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## YSHSfan (Jun 25, 2014)

I as well think the it is being confused with 165 in lbs. For a torque of 165 ft lbs it would have to have 9/16" or larger head bolts (it is impossible for that small engine to have such big bolts).
Maybe this would help: (notice that the head torque values are in _*In Lbs*_)
 B&S torque chart


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## YSHSfan (Jun 25, 2014)

Since you loosened all the head bolts, I would remove de head, inspect while apart, clean it as needed and if all is good repalce the head gasket and sequentially torque it to its proper value wich is likely to be 165 _*in lsbs*_ (14 ft lbs).


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## Kiss4aFrog (Nov 3, 2013)

Do yourself a favor and get a new head gasket. The problem is it's not like a rubber band where you can stretch (compress) it again and it'll hold. It MAY hold but then again it would be easier for it to leak or blow out.
If it's your main or only blower it's so much smarter to just replace.


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## AL- (Oct 27, 2014)

Well the mystery is solved. My torque wrench is in "ft. lbs." which I noticed and I didn't notice that the service manual was in" in. lbs.". Seemed like a big discrepancy. 
When I re read the service manual I also noticed that the 165 in. lbs. was for series 140000 and all other engines is 140 in. lbs. - mine is a series 100000. Need to use an in. lbs. torque wrench. I will use a new gasket.
When I took the head off I saw about a dozen spaced fine vertical scratches around the cylinder wall, most of them were on the opposite side of the intake/outtake ports. There was some carbon caked on the head and bit on the valve areas. I added a photo attachment. I was wondering if the scratches were caused by something, maybe in the oil? Are there ways to clean out the oil chamber before running the engine. Since the gas tank and carberetor are off the engine I could warm it up with a heater and drain out whats in there , but thought there might be some slug left as it been sitting for quite awhile. And thanks much everybody.


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## YSHSfan (Jun 25, 2014)

You don't really need an _in lbs torque wrench_, you can still use your _ft lb torque wrench_. All you need to do is *convert 140 in lbs into ft lbs*, wich comes to be *11.67 ft lbs*. You can safely _*torque them to 12 ft lbs *using your ft lb torque wrench._


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