Question about Rod and Main Bolts

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94f150rules
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Question about Rod and Main Bolts

Post #1 by 94f150rules » Tue Jul 10, 2018 5:15 pm

I have a 94 F150 4.9 5speed, this weekend Im doing a bunch of work on it and I will have the oil pan out. I have good oil pressure right now, but I figure while the pan is out I should check the rod and main bearings, to see if theyre getting worn and replace them before they go. On all the 70s cars I'm used to this isnt a problem, but the last 2 "newer" cars I tried this on one was the 4.6 in my Mark VIII and the other a 93 Caviler with a 3.1 both had Torque to main and rod Yield bolts. So to my surprise I spent a bunch of extra money on replacement bolts. Does the 4.9 have regular bolts or torque to yield?

jason832
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Re: Question about Rod and Main Bolts

Post #2 by jason832 » Tue Jul 10, 2018 6:12 pm

I don't think they are torque to yield someone else should answer as well. Also if you need to change the bolts the rods would need to be resized after pressing in new ones.

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MechRick
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Re: Question about Rod and Main Bolts

Post #3 by MechRick » Tue Jul 10, 2018 8:32 pm

Main and rod bolts and nuts can be reused. Replacing rod bolts would likely require resizing, as jason832 states.

While you have the pan off, peek at the piston skirts. A broken one should be obvious with remnants in the bottom of the pan.
1994 F150, 4.9L/ZF 5 speed, C-Vic police driveshaft
EFI head w/mild port work, 3 angle valve job
1996 long block, stock pistons, ARP rod bolts
Stock cam, aluminum cam gear
Hedman header, full mandrel bent duals, crossover, super turbos
http://fordsix.com/forum/viewtopic.php?f=2&t=73244
Bronco II with a 2.3L swap http://fordsix.com/forum/viewtopic.php?f=13&t=72863
1988 F250 2x4, 460 ZF 5 speed.

94f150rules
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Joined: Wed Nov 29, 2017 5:17 pm

Re: Question about Rod and Main Bolts

Post #4 by 94f150rules » Tue Jul 10, 2018 9:26 pm

OK, thats great to hear. I may just do the bearings for the heck of it while its open. Thanks guys

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