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View Full Version : non-interference engine YIPEE!



SoTxVx
06/03/2011, 07:45 PM
Four leasons learned over the last week...

1. We have a non-interference engine

2. Don't buy aftermarket timing belt components. If you do, pay very close attention to the tensioner pivot bolt and the torque applied to it.

3. If you break the tensioner pivot bolt, take your time, pull the grill, bumper, radiator and condenser first. It makes access to the center of the bolt with a good cordless drill a lot easier. Make absolutely, positively, without fail sure your pilot hole is in the center. If you are off center you will struggle to remove it.

4. If you break off an easy out in the bolt, it can be a real pain in the arse to remove.

Short story ...

Purchased a gates timing component and water pump kit. It was $303 from Napa, has a NTN tensioner (same as OEM) and the bearings are the same make and model as the OEM items. Non OEM was the tensioner pivot bolt, belt and water pump. I installed everything without issue but did not put a torque wrench on the tensioner pivot bolt. Probably had it torqued to 55-60 ft lbs.

Truck ran fine for about a week and early in the morning at 2500 rpms the timing belt tenionser pivot bolt sheared right at the transition from the shoulder down to the threaded portion. Bad news I am left on the side of the road right before a pretty major intersection. Good news is that no valves were damaged and the Vehicross is running just fine now.

Modified the tensioner pivot bolt to a two piece assembly as opposed to 1 solid piece. I used 10MM X 1.5 X 125MM socket head shoulder bolt to make a stud. The 10 X 1.5 MM is the same size/pitch as the block. The stud will bottom out in the block going in 4 or 5 threads depper than the original bolt. I cut off the head and threaded about 2" the shoulder with a 3/8 fine threads and left about 1" unthreaded. Milled off the head of the original bolt and bored the center to accept the shoulder bolt now acting as a stud. Reassembled the tensioner pulley assembly using a 3/8 fine thread nylon insert lock nut. Ground off the excess length of the stud level with the nut and peened it in place. Not going to have that problem again.

If you follow the instructions on how to time the camshafts on an engine that had lost it's timing belt to the letter, it works. It worked for me and it will work for you but only if you follow it exactly.

If yo

Y33TREKker
06/04/2011, 10:18 AM
Damn. Glad to hear that didn't turn into a more serious issue (as if what happened wasn't serious enough that is).

Monstertrucker
06/04/2011, 04:09 PM
Don't ARP make a bolt for this? I'll look it up.

Ok, didn't see one in their catalog but they do have a Special Projects Dept. on 805-525-1497. Might be worth enquiring about a group buy.