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dave_vic_ozz

CA18 head bolts

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I have an issue with a head bolt braking when installing a new head gasket.

 

I have had the head off a few times in the past to add hot cams and other head mods and have done lots of motors.

 

I just blew a head gasket as I have set my motor up to pull 9000rpm as it has pulls hard from 6000 to 8500rpm (Cams extractors and other stuff). Got a new head gasket and new head bolts. I always follow the instructions and lowered the head down, dropped in the bolts tightened to the 29Nm then wound it down to 103Nm of torque. As I was doing the first bolt to 103Nm it felt wrong. It was winding the bolt in too far. So I tried number 2 and the same thing. I thought the gasket must be real spongy. I checked I hadn't pinched a cable or something so lowered the wrench setting to 50Nm and brought everything to that. Up to 70 and it felt wrong so I got another tension wrench. It felt the same so I checked it in the vice and against an older style wrench to see if they all agreed which they did. All wrenches working fine. Got everything to 60Nm now. Then 70 Nm and new it was not right.

 

Tried for 80Nm and number 3 in the order snapped.

 

I pulled the head off and the broken bit of bolt in number 3 wound out with strong tweezers so it was not seized or anything.

 

So I figure these bolts are either duds or I need to get stronger bolts for my application as they stretch so much.

 

 

What type / brand of bolt would you recommend?

 

Someone suggested Studs but at $200 plus for a set I am unsure if this is the way to go. Standard bolts vary $20 to $50 depending on the brand. Standard bolts are for both Turbo and Non Turbo but what to use on a modified motor?

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I have an issue with a head bolt braking when installing a new head gasket.

 

I have had the head off a few times in the past to add hot cams and other head mods and have done lots of motors.

 

I just blew a head gasket as I have set my motor up to pull 9000rpm as it has pulls hard from 6000 to 8500rpm (Cams extractors and other stuff). Got a new head gasket and new head bolts. I always follow the instructions and lowered the head down, dropped in the bolts tightened to the 29Nm then wound it down to 103Nm of torque. As I was doing the first bolt to 103Nm it felt wrong. It was winding the bolt in too far. So I tried number 2 and the same thing. I thought the gasket must be real spongy. I checked I hadn't pinched a cable or something so lowered the wrench setting to 50Nm and brought everything to that. Up to 70 and it felt wrong so I got another tension wrench. It felt the same so I checked it in the vice and against an older style wrench to see if they all agreed which they did. All wrenches working fine. Got everything to 60Nm now. Then 70 Nm and new it was not right.

 

Tried for 80Nm and number 3 in the order snapped.

 

I pulled the head off and the broken bit of bolt in number 3 wound out with strong tweezers so it was not seized or anything.

 

So I figure these bolts are either duds or I need to get stronger bolts for my application as they stretch so much.

 

 

What type / brand of bolt would you recommend?

 

Someone suggested Studs but at $200 plus for a set I am unsure if this is the way to go. Standard bolts vary $20 to $50 depending on the brand. Standard bolts are for both Turbo and Non Turbo but what to use on a modified motor?

 

 

I had an issue very recently helping a mate building his CA, he bought a set of brand new head bolts (I cant remember the brand) but they were cheap about 30 bucks.. They felt light and had a matt black finish...

 

They were terrible, the shaft physically twisted whilst applying the torque process on two of them.. I could feel that it wasn't right and stopped straight away before snapping them...

 

I will find out the brand... Maybe a similar issue to what you are having..

 

Genuine or ARP are the way to go, you can try another cheap set but too me it just isn't worth the risk..

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I have an issue with a head bolt braking when installing a new head gasket.

 

I have had the head off a few times in the past to add hot cams and other head mods and have done lots of motors.

 

I just blew a head gasket as I have set my motor up to pull 9000rpm as it has pulls hard from 6000 to 8500rpm (Cams extractors and other stuff). Got a new head gasket and new head bolts. I always follow the instructions and lowered the head down, dropped in the bolts tightened to the 29Nm then wound it down to 103Nm of torque. As I was doing the first bolt to 103Nm it felt wrong. It was winding the bolt in too far. So I tried number 2 and the same thing. I thought the gasket must be real spongy. I checked I hadn't pinched a cable or something so lowered the wrench setting to 50Nm and brought everything to that. Up to 70 and it felt wrong so I got another tension wrench. It felt the same so I checked it in the vice and against an older style wrench to see if they all agreed which they did. All wrenches working fine. Got everything to 60Nm now. Then 70 Nm and new it was not right.

 

Tried for 80Nm and number 3 in the order snapped.

 

I pulled the head off and the broken bit of bolt in number 3 wound out with strong tweezers so it was not seized or anything.

 

So I figure these bolts are either duds or I need to get stronger bolts for my application as they stretch so much.

 

 

What type / brand of bolt would you recommend?

 

Someone suggested Studs but at $200 plus for a set I am unsure if this is the way to go. Standard bolts vary $20 to $50 depending on the brand. Standard bolts are for both Turbo and Non Turbo but what to use on a modified motor?

 

what standard bolts are $20-$50???? brand new oems are $87

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what standard bolts are $20-$50???? brand new oems are $87

 

Burson bolts were $40ish. Engine rebuilder said From $20 but not a proper quote.

 

What dealer said $87 so I don't chase all over town?

 

do you have a part number.

 

The bolts I got were Permaseal brand. Usually good stuff but not 103Nm strong. Elastic to plastic at a lot less Nm and may be why I lost a gasket.

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what standard bolts are $20-$50???? brand new oems are $87

 

Burson bolts were $40ish. Engine rebuilder said From $20 but not a proper quote.

 

What dealer said $87 so I don't chase all over town?

 

do you have a part number.

 

The bolts I got were Permaseal brand. Usually good stuff but not 103Nm strong. Elastic to plastic at a lot less Nm and may be why I lost a gasket.

any nissan dealership will get you genuine ones for $87

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