Hi all I know this is the J/K section but i was wondering if anybody had any suggestions. My friend has a 1997 and is haveing some trouble.

has anybody had problems with there timing chain jumping time? this is a 1997 2.5 liter and won't start. what ttpe of gears are they? plastic or steel?

The rotor does not line up with number one when the crank is at top dead center.

any suggestions would be appreciated?

 

Anyone there ?

 

All pushrod engines use a large steel link chain mated to a gear on the end of the cam and a gear on the crankshaft. Back in the old days chains would ''stretch'' slightly on a almost new car causing noise at the front of the engine. To stop this sort of complaint the car companies started specifying a nylon coated gear bolted to the cam. this absorbed slack in the timing chain and prevented noise. Newer timing chains are better quality, but the nylon gears are still there. Get 100,000 miles or so on your vehicle, do a hard snatch or a backfire and you very easily can have the engine ''jump'' time. ( valvetrain parts get out of syncronization). Many modern belt- driven overhead cam engines bend valves when this happens, but it's almost unheard of in a pushrod engine. Go to any of the large auto parts chains and buy a timing gear set. They'll know what you are asking for. All aftermarket gears I've seen have been all steel, no nylon overmould. Quiet too. The timing set will consist of a new cam gear, a crank gear and chain. Remember the gasket set or RTV sealer. Don't forget to re-install the slinger ring behind the crank gear or your timing cover crank seal will leak. Oh yeah, replace the cover seal too.....hope this helps

 

Pull the timing chain cover and there will be index marks on both the crank gear and the cam gear.
If they're not lined up with the crank at 12 o'clock and the cam at 6 o'clock

 

Perfect this answers alot ,he said it backfired on the way home. thanks for your help.

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