Strange knocking sound @ idle. 3200GTA

Tamariini

Junior Member
Messages
38
#1
Hi There!

I have been experiencing knocking sound from the enginebay all time i have owned my 3200. Sound has not bothered me much since it is really low volume knock and everything is working like it should. At first i thought it was tappet noise and adjusted valves but it was not that. I also checked crank end float to be on the safe side but it was ok.

During winter storage i thought that it would be finally nice to find a reason for that knock though so i took car on ramps and listened it carefully. Sound is louder below the car and knocking seems to begin when engine is close to normal operation temperature and is coming from the gearbox end of the engine, or it might even come from the gearbox or torque converter.

Has anyone of you experienced similar with your 3200's and what was the cause?
 
Messages
600
#2
Automatic? Funny enough I asked about this at last service time, if it sounds like a worn camshaft/lifter it's actually the torque converter and its normal. It resonates a mild knocking sound through the unit that sounds like it's coming from the engine. Don't worry about it :)
 

Tamariini

Junior Member
Messages
38
#3
Yes, automatic 2001, just like yours =)

It is very good to know that knocking sound could be normal. I recorded quick video of it from under the car, does yours sound the same? Does sound change when you put car on N or D or R since mine does not.

 
Messages
1,924
#4
I have a noise when the car is cold, but its gone at running temperature, and I am pretty sure it does not sound like that when its warm. How easy was the valve adjustment? Its a job on my list!!
 
Messages
1,924
#7
also for the replacement shims did you get a whole bunch of them or how did you handle changing the sizes? I see the shims are £6 a pop, so buying a range of these could be quite a proposition?
 

Tamariini

Junior Member
Messages
38
#8
Yes, i did timing + cambelt & waterpump of course. I checked clearances and existing shim thicknesses and ordered shims i needed after that. I had to change something like 18 shims but was able to swap their places so only needed to buy new ones less than 10
 

conaero

Forum Owner
Messages
28,015
#9
Get a length of air pipe, put it to your ear and check the tappets first then go on round the engine till you identify where the strongest sound is coming from.

Does it go if you put the clutch down or is it auto?
 
Messages
600
#10
Yes, automatic 2001, just like yours =)

It is very good to know that knocking sound could be normal. I recorded quick video of it from under the car, does yours sound the same? Does sound change when you put car on N or D or R since mine does not.

Does that sound louder in the vid than it actually is? Mine does it but it doesn't sound as loud as that, then again I've not listened to it from underneath, just from top. BTW the info I had came from a well respected indi who listened to it after I asked about having the valves shimmed (like you I thought it was a valve clearance issue)
What cost is the Maserati tool to do these?
There is this as well, might be handy to have.
http://www.hillengineering.co.uk/tools/engine-related-2/valve-shim-tools/-900026000
 
Messages
3,961
#11
If you have a manual 3200, the old Getrag gearbox tends to clack around in neutral on tick over, as long as everything goes quite when push the clutch down!

Dave
 
Messages
553
#12
Mine sounded like that - don't trust indies to diagnose as you'll end up with a big bill to not sort it out - trust me I know. It was the torque converter in the end but not a problem so lived with the embarrassment.
 
Messages
600
#13
Mine sounded like that - don't trust indies to diagnose as you'll end up with a big bill to not sort it out - trust me I know. It was the torque converter in the end but not a problem so lived with the embarrassment.
A well respected indi that also sponsors this forum I should add, I trust his judgment ;)
 

Tamariini

Junior Member
Messages
38
#14
Does that sound louder in the vid than it actually is? Mine does it but it doesn't sound as loud as that, then again I've not listened to it from underneath, just from top. BTW the info I had came from a well respected indi who listened to it after I asked about having the valves shimmed (like you I thought it was a valve clearance issue)
What cost is the Maserati tool to do these?
There is this as well, might be handy to have.
http://www.hillengineering.co.uk/tools/engine-related-2/valve-shim-tools/-900026000
No, it sounds very similar "live". From the top it is not worse than valves in need of adjustment. actually that hill engineering tool is exactly what i bought. I think it is a "improved copy" of original Maserati tool?

If you have a manual 3200, the old Getrag gearbox tends to clack around in neutral on tick over, as long as everything goes quite when push the clutch down!

Dave
Mine is Automatic BTR

Mine sounded like that - don't trust indies to diagnose as you'll end up with a big bill to not sort it out - trust me I know. It was the torque converter in the end but not a problem so lived with the embarrassment.
Ok, so you did'nt do anything for it and car was working ok? I am a bit annoyed about the noise... and i have worries if something breaks because of that sound...
 
Messages
38
#15
I've now been spending some time in youtube listening videos with tag "flexplate knock" and "torque converter knock" and loose flexplate gives exactly similar sound to mine...

one example:

I think during the winter i will take gearbox out and check to prevent further damage... Just in case, it's not a big task. Anyone knows if one could use Ford Falcon torque converters on these since they are using same gearboxes? There is a lot of knowledge on these boxes and torque converters in australia and possibly some performance parts available from there.

edit: and something like this would be a nice feature with flaps on steering column =) https://www.shiftkits.com.au/shop/btr-4-speed-full-manual-transmission-controller/
 
Last edited:
Messages
373
#16
You won’t be able to use a torque converter from a different engine, although externally similar the internal vanes are designed to suit the torque curve of the particular engine.

Torque converters can be refurbished as if they fail it’s usually either seals or the lock up clutch.