knocking sound when a/c on

[harold30]

Hi guys,

After fixing the problem i encountered when swapping with m50 injectors, and yet another problem pop, up which is a knocking sound when A/C switching on. No issues turning on the recycle switch and fan speed 1-4.

I looked on realoem for air conditioning components that would be constantly moving when staring the a/c and the results are condenser fan and compressor.

Could one of these will cause the knocking sound? Or I'm looking at wrong direction.

Please advise.

Thanks!

[harold30]

Seems like the knocking sound came from under the head but when I switch off a/c the sound will gone. I adjusted my valves 4 months ago and sound stronger than rocker arms even on normal temp.

Could this be a rod knock or piston slap? If so, how come the it will gone when turning off the a/c?

Any ideas?

[harold30]

I think I figured it out.

It so happen that the push rod of my clutch master cylinder is broken and still driving the car while still waiting for the new part to arrive before installing the injectorors.

I took the car for a drive for about 30 mins and when I parked my car in the garage and the press the clutch pedal the knocking went out. So must be the release bearing is the culprit due to bad clutch master cylinder. But I changed clutch kit 9 months ago.

Perhaps the pressure is not right inside a broken cylinder. Will have to wait when the new clutch master cylinder to arrive and installed and see how it goes...

[Poorboyz]

Ahhhh...sounds like the Getrag rattle. I just fixed my trans from doing that.

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[FLG]

Sounds like it could be typical getrag rattle. You learn to live with it.

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[harold30]

Ahhhh...sounds like the Getrag rattle. I just fixed my trans from doing that.
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Is it the transmission you have fixed? or changed release bearing?

[FLG]

Is it the transmission you have fixed? or changed release bearing?

There really is no "fix" I remember some people saying some fluids help or lessen it but really you just need to live with it.

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[Poorboyz]

Is it the transmission you have fixed? or changed release bearing?

Getrag rattle is not the release bearing, its the input shaft bearing and or the countershaft bearing.

There really is no "fix" I remember some people saying some fluids help or lessen it but really you just need to live with it.

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I couldn't live with it so I opened up my trans and changed bearings.



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[FLG]

Ah... I thought some of it had to do with the gear tolerances and them just rattling off each other?

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[Poorboyz]

Ah... I thought some of it had to do with the gear tolerances and them just rattling off each other?

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No, its usually either the input shaft ball bearings slapping against each other like in my case, the countershaft bearings slapping against the dust cover/seal or both.

As it cab be seen in my pictures the old bearing was missing the plastic retainers that keeps each ball bearings separated..mine cracked, chipped, broke off and caused ball bearings to slap against each other.

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[harold30]

No, its usually either the input shaft ball bearings slapping against each other like in my case, the countershaft bearings slapping against the dust cover/seal or both.

As it cab be seen in my pictures the old bearing was missing the plastic retainers that keeps each ball bearings separated..mine cracked, chipped, broke off and caused ball bearings to slap against each other.

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That is nasty.

Do you have a part numbers for both? Might as well I'll look at them at realoem.

[Quinthirty]

Oh, there you go, Harold. I'm wondering now if anyone has the same experience on an 4HP22 tranny.

[Poorboyz]

That is nasty.

Do you have a part numbers for both? Might as well I'll look at them at realoem.

I do have the part numbers but I will have to get them for you tonight when I get home.

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