Prius head gasket job - broken cam bolt

1. I would just replace the broken bolt.

2. For replacement bolt see schema 2/2 (near bottom of page) here:

https://www.amayama.com/en/genuine-catalogs/epc/toyota-usa/prius/ZVW30L/13502/engine/1104

note: the link is to a regular, 2012, US, hatchback Prius. I believe yours is a Prius v? As far as I know the cylinder head is identical, but you could confirm by entering part no and your VIN on Toyota USA parts site.

 

Just replace the cam bolt you mite find at tractor supply . Not mission critical . Just a bolt. As you found out . Junk yard . A shop floor etc .

 

What torque value? Screen grab from last link in my signature*:



* on a phone turn it landscape to see signatures

 

If you don't get the specific bolt from Toyota, make sure to get the same length and grade so it'll stand up to the same torque conditions.

 

I cannot believe that anything in the vague ball park of 20lbs of torque would twist one of those bolts off..... Wow. Agree with new torque wrench. Are you new to this stuff? I ask because most of us who have "wrenched" for a while have a approximate idea of how tight to tighten a bolt and when too much is too much. Not accusing you of being dumb, but experience has its perks........

 

Hopefully better than the last bolts torque conditions...

 

A Sears employee told me years ago, you don’t want to use a torque wrench near its extremes. 1/2” drives are good for wheel lug nuts, suspensions. 3/8” have lower range, appropriate for brakes, oil changes, and 1/4” (typically incremented inch-pounds, values 12 fold of foot-pounds) are for spark plugs, throttle body hold-down bolts, battery connections.

I’ve had a 1/2” drive for about 40 years, but in the last decade acquired 3/8” and 1/4”. Made in China, decent quality/accuracy, are about $30~40 CDN. I’ve “tested” them by clamping the fulcrums in a vice, arms horizontally, suspending known weight at calculated distance along the handle, and all 3 where surprisingly accurate.

There’s “factors” too, well oiled threads for example, will turn (and tension) more.

did you note in pic I posted above, there’s 20 and 12 foot-pound values? Thelong versus short apparently. You’re more familiar than me, having dealt with these; I’d gather the two kinds of bolts serve different purposes?