There's been a bunch of discussion re fuel rail cracking and its cause. Yes, the balance shafts could be out of time, but having healthy motor mounts is just as important for reliability of the fuel rail. Good mounts and correctly set up balance belt = minimal vibrations.
Excessive vibration due to bad motor mounts also causes cracked oil suction tubes. Also dip stick tubes if they aren't secured.
Timmy's tech tip # 349.
The engine torques to the passenger side under throttle. If the right side mount is tired or collapsed, it forces the whole drive train i.e., engine, torque tube, tranny, to twist that way. This affects the angle of the axles coming out of the tranny which will affect CV joint wear and HP to the ground. Go to the rear of your car right now and see if your tranny is hanging level or not. If it's not level it could be a bad motor mount up front. Remember to loosen the four 17mm head bolts at the front of the torque tube whenever you change the mounts or the tranny. This will allow the tranny to hang level again, then tighten them down.
Another sign that your motor mounts are bad is if you can see an inch of oil pan hanging down lower than the cross member. YIKES!
Buy GOOD motor mounts:
In my opinion,
1. MEYLE, Hamburg technik, Uro brand are NOT good mounts. They are cheap at around $40 and are typically only rubber, not hydraulic AND rubber. We've had these brands fail in 1 year on street cars.
2. Factory mounts are the answer. (CORTECO is an OEM supplier)These are both rubber and hydraulic and will cost a couple hundred for each side, however, they will do the job much better and for a WAY longer time. Reliability is what we want.
Also, consider that every time the engine rolls to the right too much, it fatigues and even loosens things like the radiator hoses, the engine wiring harness, the rubber J boot to the AFM, and anything else that is attached both to the chassis AND the engine.
Motor mounts are more important than you think!
Good luck for the 2017 944 Spec season!
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