Is jack shaft front bolt supposed to be reused?

[dcm0123]

1999 Explorer Sport 4.0 SOHC 4WD

Some one set the timing up wrong in this vehicle when they replaced the main timing chain, guides and tensioner. It ran but lacked power. Found both cams timed correctly to each other but they were off about 10 degrees from crank so I need to reset the jack shaft gear.

Using OTC tool to set up timing.

Ford manual says torque bolt to 33 foot pounds then 1/4 additional turn. Says nothing about it being a torque to yield bolt.

Ford kits come with a new bolt but aftermarket kits do not.

Anyone run into this before?

 

[BenII]

They say no but I refused mine w/ no problems. Trick is take it to a machine and have it mic"d for length. If it isn't stretched reuse it.

 

[Mbrooks420]

They say no but I refused mine w/ no problems. Trick is take it to a machine and have it mic"d for length. If it isn't stretched reuse it.

I doubt you can get the specs for a correct length bolt. Bolts are very rarely machined for length, I’d bet money if you ordered 10, they’d all vary. You’d probably be better off running it through a die to see if it were stretched. It’d want to cut from the end, but go on appropriately after the stretched portion.

Instead of all that, I’d just go buy a new bolt.

 

[BenII]

I doubt you can get the specs for a correct length bolt. Bolts are very rarely machined for length, I’d bet money if you ordered 10, they’d all vary. You’d probably be better off running it through a die to see if it were stretched. It’d want to cut from the end, but go on appropriately after the stretched portion.

Instead of all that, I’d just go buy a new bolt.

I figured the guy didn't have the 45.00 to spend on one bolt. The machine shop must've billed me looking up the specs on this bolt. Either way mines fine for now.

 

[Mbrooks420]

$45 will seem like a bargain if that bolt fails. If it’s TTY, replace it.

A machine shop didn’t just measure the bolt for length. They most likely compared the thread pitch in two places on the bolt, or the end of the threads vs what the nominal value is on a thread chart.

 

[BenII]

$45 will seem like a bargain if that bolt fails. If it’s TTY, replace it.

A machine shop didn’t just measure the bolt for length. They most likely compared the thread pitch in two places on the bolt, or the end of the threads vs what the nominal value is on a thread chart.

 

[BenII]

That could be what the parts guy did. He wasn't gone long. But he mentioned measuring it. I never thought it was a thread pitch gauge. Any way I reused it and it's good so far.

 

[Runnin'OnEmpty]

Ford manual says torque bolt to 33 foot pounds then 1/4 additional turn. Says nothing about it being a torque to yield bolt?.....

Those torque specs indicate it's indeed a TTY bolt. A reusable type would have a specific torque range.

 

[Fix4Dirt]

$45 will seem like a bargain if that bolt fails. If it’s TTY, replace it.

A machine shop didn’t just measure the bolt for length. They most likely compared the thread pitch in two places on the bolt, or the end of the threads vs what the nominal value is on a thread chart.

yeah 45 bucks to sleep at night much better than a rebuild