Timing belt broke on my truck


#1

1998 Mazda B2500. Timing belt broke while driving. How likely is it tht my valves r warped & how do I fix it?


#2

Also need to knw if my motor is interference or not…


#3


The question of whether the valves are wrecked or not pretty much is question of whether its an interference engine or not.

You can find out at the Gates website: http://www.gates.com/


#4

They say it’s not an interference engine, so you should just be able to replace the belt, and drive on.

Chase


#5

Yes…if it’s NOT a interference engine then replace (correctly) and drive away.

Happened to me with my Chevy Vega…Timing belt broke on the highway…I coasted off the highway…found a parts store two blocks away…replaced belt in 2 hours…and drove away.


#6

Just curious, was this the original timing belt?


#7

No valves bent. Replace the belt, may want to do the water pump since it’s a little bit easier with the timing cover out of the way.


#8

I believe it is the original belt. It’s got right at 109,000 miles on it. I just bought a belt. Got a guy gonna do it for 100 bucks. Is tht a good deal?


#9

It's a deal but belt tensioners/idlers should also be replaced and in some cases the water pump too. I flat do not remember the water pump setup on this model though.


#10

Ok…new problem with timing. After we replaced the belt the valves r chattering very loud. Wht do I do bout tht?


#11

He may not have installed the belt correctly…It could be off a tooth or two.


#12

Noisy valves are not a good sign, that usually indicates bent valves. I think these engines have hydraulic lifters. Remove the valve cover and grab each rocker arm and rock it. It should not rock, if it does, then that valve is probably bent. If the engine has mechanical lifters (solid lifters), about half of the rockers will rock a tiny amount, about a hundredth of an inch.

Turn the engine over one time (one whir of the starter motor) and check the rockers again. The valves under any rockers that are very loose will be suspect. If the rockers are all tight, then it could be the timing of the belt is off and the noise you are hearing is not due to the valves.

A compression test or leak down test would also be in order here. The leak down test would be the better of the two as it will detect any bent valves. A low compression reading might be interpreted as bent valves but could be due to valve timing.