• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Crankshaft diameter for main bearings 4.0l engine

oldbill

NAXJA Forum User
Location
Michigan
Can anyone tell me what the diameter of a standard size journal for the main bearings is n a 4.0L engine? Also do you know the thickness of a standard main bearing. I saw on you tube where a mechanic machined the threads off of a bolt and then machined down the thickness of the bolt head and used that to spin the main bearing in and out with the crank still installed in the engine. I'd like to make one in advance for my engine.

Thanks,
Bill
 
May be worth a look before you start, just in case your engine isn't standard.

Special-Engine-Mark-Location.png

Special-Engine-Marks.png


Been my experience the mains are less a problem than the connecting rod bearings and the connecting rod bearings wear much quicker than the mains do.

Second tip. just doing the bearings without facing the crank may be a waste of time, the crank often wears more in one area than the other and not constant across the face. Third tip a little loose is better than too tight.
 
May be worth a look before you start, just in case your engine isn't standard.

Special-Engine-Mark-Location.png

Special-Engine-Marks.png


Been my experience the mains are less a problem than the connecting rod bearings and the connecting rod bearings wear much quicker than the mains do.

Second tip. just doing the bearings without facing the crank may be a waste of time, the crank often wears more in one area than the other and not constant across the face. Third tip a little loose is better than too tight.
 
Back
Top