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  #16  
Old July 13th, 2018, 16:04
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

I'm just wondering how bad it would be to re use this bolt I should have just gone to the dealership or ordered a new set of arp...i torqued it down and then backed it off and torqued it down again. However id still like to know the cause of something that is causing me to lose time and money ive already broken a brand new bolt and have another new one slipping. Right now I'm thinking the oil and new machined surfaces are slipping but I'm seeing you SHOULDuse oil. Is thetr supposed to be oil between the washer and the head?
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  #17  
Old July 13th, 2018, 17:06
trippled trippled is offline
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Re: Cylinder head bolts

I'm confused. In your first post you said you broke it with anti seize, now you say you broke it with oil. The head bolt torque values are designed with oiled threads, bolt head and washer. Nothing else.

If you broke the bolt with oiled threads and bolt head and washer, either the bolt was bad, your torque wrench is crap or you have some Burr or oil in the hole locking the bolt up.
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  #18  
Old July 13th, 2018, 17:12
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8Mud 8Mud is offline
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Re: Cylinder head bolts

I'm far from an 4.0 expert, but have done many heads on pumps, industrial machinery and various motors.

Used to be the bolts could be reused once, seems to be not recommended now. Next question, are you reusing the same head gasket? Different designs of head gasket, most have a slight bit of crush built in. I wouldn't use the same head gasket.

The one that broke doesn't concern me as much as the one you say slipped. Possible the one that broke was flawed. Are the threads in the block OK. The threads on the bolt OK? Can you see any metal pieces in the threads?

I don't oil the threads before torquing, in most instances. The torque readings are dry torque, unless otherwise specified.

I have a set of thread chasers, a shop vac comes in handy. Thread chasers work better than taps, especially on blind holes.

Used to be (when I was taught in the middle of the last century) wet torque was 10% less than dry torque as a rule, things change. I'm really good about cleaning threads really well. Brake cleaner and air work well, maybe a small round brush if needed. I use nylon gun bore brushes or eve brass bore brushes for stubborn stuff.

One of my most used tools is a good powerful flashlight and a welders mirror as needed.

Another thought did you clean out the dowel holes? Is your head and block straight? I've seen heads with significant warp or bow. A good straight edge and a flashlight behind the straight edge can do a quick check.

Are you torquing correctly, in stages and the right sequence?

One in a hundred chance, but are you sure your torque wrench is good?
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  #19  
Old July 13th, 2018, 17:16
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

Quote:
Originally Posted by trippled View Post
I'm confused. In your first post you said you broke it with anti seize, now you say you broke it with oil. The head bolt torque values are designed with oiled threads, bolt head and washer. Nothing else.

If you broke the bolt with oiled threads and bolt head and washer, either the bolt was bad, your torque wrench is crap or you have some Burr or oil in the hole locking the bolt up.
2 different sets of bolts yes.
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  #20  
Old July 13th, 2018, 17:23
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

Quote:
Originally Posted by 8Mud View Post
I'm far from an 4.0 expert, but have done many heads on pumps, industrial machinery and various motors.

Used to be the bolts could be reused once, seems to be not recommended now. Next question, are you reusing the same head gasket? Different designs of head gasket, most have a slight bit of crush built in. I wouldn't use the same head gasket.

The one that broke doesn't concern me as much as the one you say slipped. Possible the one that broke was flawed. Are the threads in the block OK. The threads on the bolt OK? Can you see any metal pieces in the threads?

I don't oil the threads before torquing, in most instances. The torque readings are dry torque, unless otherwise specified.

I have a set of thread chasers, a shop vac comes in handy. Thread chasers work better than taps, especially on blind holes.

Used to be (when I was taught in the middle of the last century) wet torque was 10% less than dry torque as a rule, things change. I'm really good about cleaning threads really well. Brake cleaner and air work well, maybe a small round brush if needed. I use nylon gun bore brushes or eve brass bore brushes for stubborn stuff.

One of my most used tools is a good powerful flashlight and a welders mirror as needed.

Another thought did you clean out the dowel holes? Is your head and block straight? I've seen heads with significant warp or bow. A good straight edge and a flashlight behind the straight edge can do a quick check.

Are you torquing correctly, in stages and the right sequence?

One in a hundred chance, but are you sure your torque wrench is good?
I cleaned the bolt holes the first time and second time went in again with an old bolt with a channel cut in it vaseleone followed by brake clean and air... I didnt want to take it apart last but I only really inspected the hole with the broke bolt and the threads looked good. So since wrenched that bolt down..backed it off and then wrenched it again that counts as its lifetime right?I followed factory torque instructions.
I have a brand new clear water head I did not check my block with a straight edge.i also bougjt a new head gasket.
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  #21  
Old July 13th, 2018, 17:35
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

Last night***I having touched it since the bolt spun
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  #22  
Old July 13th, 2018, 17:35
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

Havnt* cant edit posts
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  #23  
Old July 13th, 2018, 20:13
lawsoncl lawsoncl is offline
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Re: Cylinder head bolts

Quote:
Originally Posted by 8Mud View Post
Just for info you can't trust torque wrenches. I've had moderately high end torque wrenches mess up, especially those designed to click skip when they reach to desired torque. They may work fine for many tries and then mess up once.

I had a crapsman clicker that started overtorquing by 50-lbs, and Sears refused to swap it. This was back when Home Depot accepted craftsman returns and they gave me a nicer Husky clicker in return. I periodically use a fish scale or an analog bathroom scale and check the calibration on my clickers (big socket on the receiver hitch and stand on the bathroom scale or use the fish scale to pull).
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  #24  
Old July 14th, 2018, 11:41
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

So if I torqued the bolt down, backed it off, torqued it down again didnt seem right and backed it off again...does this constititute the bolt being stretched past its life.
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  #25  
Old July 15th, 2018, 08:56
Mcmadman Mcmadman is offline
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Re: Cylinder head bolts

Quote:
Originally Posted by trippled View Post
You need to use oil on the bolt heads and threads. Anti seize reduces the friction too much. You probably went past the bolts yield and snapped it. The others sound like they have stretched too much already. I would not trust any of the head bolts you torqued with anti seize.

Engine oil works fine for the bolts. Don't need anything fancy.
So now I'm just going to try cleaning one that had antiseize seeing as though its been toqued down less than the one that I backed off and twice?
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