my daughter broke the timing belt. Is it a interference engine? the shop said i'm looking at $2200.:banghead:

According to the moderator of this forum & an expert on Neons, they are 'interference engines'. See the thread: Neon Engine issues (http://www.automotiveforums.com/vbulletin/showthread.php?t=606617) . Aside from bent valves, Im not sure the head itself would be damaged, but since the head has to come off anyway, you would want to have it examined for warping and a valve job done on it. And like the thread mentions, its a good time to replace the water pump - because replacing the timing belt gets you to the situation where the water pump is fairly easy to access. If the car has high mileage, like over 120,000, it might be a good idea to try replacing the front main crankshaft seal too, for the same reason; much of the labor to access it is already accomplished. I pulled my engine out to replace the leaking rear main seal, and did all this work because it was now easy to do. I also replaced the Cam Position Sensor and Vehicle Speed Sensor and their connectors because they looked ratty. The sensors were reasonably priced. On my 97 SOHC Neon it was Vital to ensure no part of the wiring could droop onto the metal EGR tube. It gets hot enough to melt wiring insulation.
And if the mechanic is going to take the engine out - I would have him replace the rear main seal, even if its not yet leaking.

As denisond3 already said, it is an interference engine. Timing belt, water pump and idler pulley should all be changed.

Since you have a SOHC engine, you may not have bent any valves if you are lucky. For some reason, they are a little more forgiving than the DOHC motors.

How many miles on the car?

As denisond3 already said, it is an interference engine. Timing belt, water pump and idler pulley should all be changed.

Since you have a SOHC engine, you may not have bent any valves if you are lucky. For some reason, they are a little more forgiving than the DOHC motors.

How many miles on the car?


It has 125,000. is there a way to tell if the valves are bent without taking the head off?

If the timing belt were intact, a typical compression check would tell you of bent valves; that is to crank the engine with the starter. But with the timing belt gone it would require re-installing a belt (a substantial chore) just to do a compression check. Another scheme I have used to check for 'compression' (valve integrity) would involve rotating the camshaft sprocket with a wrench, and seeing if you can pressurize each cylinder in turn as the camshaft is positioned for the pistons (one at a time) to be at the start of a 'compression stroke'. Requires an air compressor.

I did this many years ago on my 59 Jag. with its DOHC six, after the lower timing chain had skipped many teeth. That 3.5L was definitely an inteference engine. I turned the camshafts to be set for Top Dead Center on cylinder #1, i.e. the lobes angled so both valves supposedly were shut - and I turned the crank so the piston for #1 was near its bottom. Then I ran compressed air into cylinder #1 via the spark plug hole and an adapter to my air chuck. I repeated this for cylinder #2 and so on. (Was unable to pressurize the air in 3 of 6 cylinders - bent valves.) These adapters are still available, and are used for pressurizing engine cylinders to try and hold valves shut when folks are desperate enough to want to replace the valve springs with the head still on the engine.
You have to be careful about having each piston at the bottom of its stroke, or the compressed air can move that piston down Fast! I only used about 40 psi of compressed air. Even so, you need to keep out of the way of rotating parts. I dont know if auto mechanics use this technique anymore, but it was the reasonable way to check compression/valve condition on aircraft engines that didnt have starters, and vintage cars old enough that their engines didnt have starters.