Main Bearing Bolts

humblesmith · Aug 18, 2016

We are doing a total rebuild of my JD engine. I have bought new bolts for the head and for the rod bearing caps. My question is what is the risk of re-using the bolts for the main bearings? The engine did not have a lot of wear.

Bhunt · Aug 18, 2016

(quoted from post at 16:43:57 08/18/16) We are doing a total rebuild of my JD engine. I have bought new bolts for the head and for the rod bearing caps. My question is what is the risk of re-using the bolts for the main bearings? The engine did not have a lot of wear.

Slim to none if it was an aircraft you would be required to replace them simply because there part of the power plant once any bolt is Installed and torqued the bolt is essentially stretched. On an aircraft you would do a non destructive Inspection NDI the bolts for cracks if you had to reuse them. In this case its a personal choice it cant fall out of the sky.. I will be reusing my main cap bolts there's little risk if the bolts are not damaged and the threads are ok. The reason is simple because most are safety wired or have a restraining feature to prevent them from backing out. Just torque them in steps 1/3 2/3 full torque per your manual. let it set over night and recheck the full torque the next day and secure with safety wire or whatever restraining device it may have.. Someone else may chime in on this, If it makes you feel better to replace them go for it. As always the choice is yours.
Best of luck Byron

Steve@Advance · Aug 18, 2016

They will be fine. If they look good, and torque good, no problem.

dr sportster · Aug 18, 2016

Probably a higher quality of hardware than anything that you can buy today except ARP fasteners.

Mike M · Aug 18, 2016

It may depend on WHAT model JD the engine is from ? If something newer it may be required to change them.
I'd post this question down at the JD forum and include your model.

430WLPG · Aug 19, 2016

Not unless they are torque turn

buickanddeere · Aug 19, 2016

(quoted from post at 11:43:57 08/18/16) We are doing a total rebuild of my JD engine. I have bought new bolts for the head and for the rod bearing caps. My question is what is the risk of re-using the bolts for the main bearings? The engine did not have a lot of wear.

Should be good unless some Bubba in the past was too cheap to purchase a torque wrench or thought he was too skilled to need a torque wrench. Lots of loose flywheels on 70/720/730 diesels due to abubba under torquing or over torquing and stretching fasteners.

Main Bearing Bolts

humblesmith

Member

Bhunt

Member

Steve@Advance

Well-known Member

dr sportster

Well-known Member

Mike M

Well-known Member

430WLPG

Member

buickanddeere

Well-known Member

Similar threads