Diesel Engine Head Bolts

[Tinkerer]

Is it ok to reuse the head bolts when rebuilding an older (1970s) diesel engine ? Has anyone had one fail after reusing them ? Is it important to retorque them when the engine has warmed up to operating temperature the first time after replacing the head bolts.

 

[smittysrepair]

This all depends on what you are working on and how the bolts check out. Most cat engines say you can reuse the bolts. Some Deere engines are one time use only bolts. The Zetor engines I have done say to re torque after 50 or 100 hours. Of course on the re torquing the bolts. I have noticed a lot of the gasket kits that I get now will have a note with them saying there is no need to re torque because of updates in the gasket materials now being used. If you give us some more info on what you are working on I will try to help you out with it.

 

[Tinkerer]

Smitty, It is a 1978 Case TLB with a four cylinder 301B engine. I hope to do the rebuild this summer.
Thanks

 

[smittysrepair]

Tinkerer,
I think I may have a manual on that engine but I am not positive. If I get time today I will try to remember to look for it. If memory serves me correctly though I am pretty sure you can reuse those bolts. Always pay attention as you take the engine down. A bolt that is looser then the others is a good sign of a stretched bolt. If I can find a manual later today I will try to get you the measurements for the free length of the bolts. Always replace any stretched bolt no matter how minor the difference is. And another thing to look for is condition. A lot of times head bolts come out pitted on the shank of the bolt. I chunk any pitted bolt because it will be a time bomb waiting to go off if you reuse it. I will let you know what I find as soon as I get a chance.

 

[Tinkerer]

Smitty,
Thanks for the info. I will probably reuse them unless they are stretched too much. I have the shop manual but I won't have access to it for at least another week. I will post back if the bolt lengths are specified in it.
Thanks