If My Timing Belt Breaks Will My Accessory Belts Still Turn When Trying To Start The Engine

Posted in Ignition Systems | Asked on Aug 5, 2010

I think my timing belt has broken and I was wondering if a timing belt breaks will the accessory belts(they drive the AC water pump alt pw steering etc)still turn when you try to crank the engine.

When I try to start mine the accessory belts turn but the car doesn’t start.I’ve narrowed the no start down to the distributor and a broken timing belt.

Also how can I test for a spark at home?
I want to add that if the belt did break I was going about 25MPH at around 1.5-2k RPM, I heard something like a loud screech but I’ve always heard that head damage sounds like a loud rattle or clunk.The car is a 91 maxima auto.I think I may try to replace the belt myself, I have lots of tools will I need a timing light.
But do/ I need a timing light to replace the belt is it mandatory; if it mandatory for me to set the timing?I can do simple repairs but this will be my biggest repair.

There are 5 Answers for "If My Timing Belt Breaks Will My Accessory Belts Still Turn When Trying To Start The Engine"

  1. Dan B says:

    The timing belt/chain is inside the engine. If the distributor won’t turn while you are cranking the engine, it’s guaranteed that your timing belt has broken. The starter turns the crankshaft which in turn turns the accessory belt which in turn turns the accessories (AC, alternator, PS pump, etc). The distributor is turned by the cam shaft which is turned by the timing belt via the crankshaft (separate gear on the crankshaft). So, if the distributor turns, your timing belt is not broken. You have a different ignition problem or fuel delivery problem.

  2. The-Razors-Edge says:

    Yes, if you crank the engine with a broken timing belt, the only thing that will not spin is the camshaft (and possibly the balance shaft and water pump if the engine has those implements). The accessory belt has nothing to do with the timing belt. It is driven by the crankshaft pulley that is being driven by the starter through the crankshaft itself while cranking. Did I mention crank? lol. Anyway, although this is the case, if you suspect a broken timing belt, you should NOT crank the engine. You can bend valves and damage pistons if your timing belt is broken, not to mention you would have to realign the crank and cam sprockets, which can get tricky sometimes.

    To test for a spark, simply pull off a wire, attach a spare plug to the wire, and hold the plug against a metal surface somewhere on the car. Then have someone crank the engine, and see of the plug sparks. If not, then you should troubleshoot the ignition system. If so, then you have a fuel or compression issue.

  3. jvclassic says:

    If timing belt is broken or skipped, engine will have no compression and spin faster than usual.
    If that is problem, check if it is interference or Non-int. Most Toyotas and Chevys are non-int. Most Hondas and Fords are int. Broken T-belt on int. engine is Major engine damage.
    Accessory belts will spin normal.
    Check for engine spark by pulling a spark plug wire, stick screwdriver in wire end. Crank engine and place shaft near grounded clean metal. If spark jumps, you got spark.

  4. Craig Noy says:

    noooooooo buy a new timeing belt they are not hard to change and you car will not run with out it to test the spark pull the wire and hold the lead (center of the wire) to a stud and have somebody to crank the engine and if there is a spark it should arc to the stud provided that the stud is grounded

  5. ajht50 says:

    if the timing belt is broken your car wont run, the timing belt connects the cam and the crank so they spin at the same time, generally the acc belts are ran off a pully on the crank, so without the crank turning, niether will the acc belts.