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Help diagnose my ticking sound


nbristow01
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Ok I will describe as best I can. new motor, complete rebuild..head and all. used 5 speed tranny. When sitting still no tick, motor sounds healthy. When you take off you hear it. It sounds like it comes from under the car. If you sit at idle, say in the garage, rev it..no tick, push in the clutch...rev it...no tick. BUT when you are moving you have the audible tick that increases and decreases with the rev of the engine. If I am driving , say 40mph(it is not speed specific), give it gas I hear it. At same speed push in the clutch to take any load off the engine and rev it, you hear it..but sitting still rev it you don't

The tranny does have noisy bearings by the way

My guess is it is in the tranny. I think it has to do with the fact that when sitting still, the driveshaft is not spinning the tranny from that end and all is quiet. But when driving, coasting etc the tranny is spinning from the front and the driveshaft is spinning it from the rear so something in there then ticks. Anyone have an idea about what it may be?

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Ok I will describe as best I can. new motor, complete rebuild..head and all. used 5 speed tranny. When sitting still no tick, motor sounds healthy. When you take off you hear it. It sounds like it comes from under the car. If you sit at idle, say in the garage, rev it..no tick, push in the clutch...rev it...no tick. BUT when you are moving you have the audible tick that increases and decreases with the rev of the engine. If I am driving , say 40mph(it is not speed specific), give it gas I hear it. At same speed push in the clutch to take any load off the engine and rev it, you hear it..but sitting still rev it you don't

My guess is it is in the tranny. I think it has to do with the fact that when sitting still, the driveshaft is not spinning the tranny from that end and all is quiet. But when driving, coasting etc the tranny is spinning from the front and the driveshaft is spinning it from the rear so something in there then ticks. Anyone have an idea about what it may be?

Is it instead correlated with the spinning of the driveshaft?

I would check the bolts on the guibo (tighten the crap out of them), and even the nuts that secure the driveshaft to the differential (I've had them loosen on me as well). Any of those will click in the manner you described, if they're loose. Consider some new nylocks....

EDIT: Guess I could be wrong, if it correlates with engine rpm with clutch in and coasting, though...

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Guest Anonymous

But with the clutch in, the tranny is moving at a constant speed when you are rolling along, so it must be the engine.

How about running it on a lift or jack stands and carefully crawling around until you locate the spot the sound comes from?

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If it is only with the clutch pressed in, and it varies with the engine revolutions, look for a busted pressure plate to be coming your way soon...

From the been there done that recently.

Although when mine went, there was a whaccka whaccka whaccka sound, and a really bad vibration when driving. You may be in the first stages of this kind of failure....

BD

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But with the clutch in, the tranny is moving at a constant speed when you are rolling along, so it must be the engine.

How about running it on a lift or jack stands and carefully crawling around until you locate the spot the sound comes from?

Bill I went to my mechanic for that this morning. He broke out his mechanics stethascope and vanished under the car, it is sounding more and more like a rod knocking

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Is it instead correlated with the spinning of the driveshaft?

I would check the bolts on the guibo (tighten the crap out of them), and even the nuts that secure the driveshaft to the differential (I've had them loosen on me as well). Any of those will click in the manner you described, if they're loose. Consider some new nylocks....

EDIT: Guess I could be wrong, if it correlates with engine rpm with clutch in and coasting, though...

+1

Check the stiffness (or softness) of your trans mount.

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Ticking tends to be used to describe valvetrain problems. Knocking is a better description for lower end noises, like rod bearings. Reving up the engine such as on the freeway is going to result in higher oil pressure (pump spinning faster), so the noise should get quieter because more pressure is fed to the bearings. If you are convinced on the lower end being the problem, try to duplicate the problem with the car stationary. Pull each plug wire (with insulated pliers) and see if killing any cylinder quiets in down.

I had an engine with foriegn material jumping between cylinders, smashing up the pistons and combustion chamber, that made a ticking sound, but sounded much more like it was coming from the lower end. If you can get a boroscope into the plug holes and take a look around, you can eliminate that possibility. I should add though, that sound was constant regardless of load.

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