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Technical => Engine Tech Forum => Topic started by: neil68 on July 15, 2010, 06:34:40 PM

Title: Engine "chirps"...MSD
Post by: neil68 on July 15, 2010, 06:34:40 PM

Looking for some suggestions.  My engine has picked up an annoying "chirp" that I'm trying to trouble-shoot.  It varies with rpm and is not the fan/gen, as it's still present when the belt is removed.  It sounds like it's coming from the MSD distributor-fuel pump area.  The rear pulley tin all clears fine, so I've ruled out tin interference.

Has anyone using an MSD disty had lubrication problems that create a noise?  Could the fuel pump rod be squeaking?  I've never encountered this in all my years of driving Beetles.  Had two other mechanics look at it, and the best they came up with, was possibly the distributor or fuel pump.  I've read that the MSD 6AL can also "chirp" (and it's apparently not a problem, other than the noise) but mine's located under the back seat, so I don't think that's the sound I'm hearing.

Any other suggestions or agreement with the above possibilities?

Thanks!

Title: Re: Engine "chirps"...MSD
Post by: Chris on July 15, 2010, 11:53:30 PM

so its consistent, its always present and more often with increase in rpm?

Title: Re: Engine "chirps"...MSD
Post by: Geoff on July 16, 2010, 08:06:06 AM

A common "Chirp" sound or whistle was always a problem when running Dellorto DRLA carbs before the vibration dampners came out, they have a little bump that fills a space in the bottom of the carb to stop the noise. That info is for those with Dell's, If I remember correct you have good old IDA's. In that case it's probably not a loose carb but check the manifold bolts and carb bolts to be sure.

Yes I have heard the MSD make a chirping sound but I can't remember what the remedy was.

G.

Title: Re: Engine "chirps"...MSD
Post by: neil68 on July 16, 2010, 06:31:44 PM

This has me puzzled:

-swapped spare fuel pump and checked pump rod/lubed
-removed distributor, cleaned, lubed
-removed rear tin
-found one loose sled tin #1
-checked pushrods, rockers
-found a loose manifold nut on #3
-checked pulley (lubed pulley-to-case opening to see if that would quiet it)

after all this, there is still the same annoying chirping noise.  It varies with rpm, so it must be something rotational.  Could this possibly be something internal, ie. #4 main bearing?  Or, perhaps clutch related?  Trying to "rule out" the bolt on stuff first, before considering pulling the motor...

Title: Re: Engine "chirps"...MSD
Post by: Hansk on July 16, 2010, 10:06:27 PM

Cam gear come loose ? Hate to think it , just throwing it out there.  Or cam gear bolts hitting oil pump?

Title: Re: Engine "chirps"...MSD
Post by: neil68 on July 16, 2010, 11:06:35 PM

good suggestion!  I'll remove the oil pump and look at the cam bolts before resorting to pulling the engine...

Title: Re: Engine "chirps"...MSD
Post by: jim martin on July 18, 2010, 05:37:12 AM

i've had a few weird noises .
- grab the small pulley on your alternator or generator and push it in and out ,checking for end play and noise.found the plate that holds the inner bearing at the fan end was missing 1 screw and the other was half out .would make different noises depending on its mood .knocking , scaping and chirping
-grab the large crank pulley and push it in and out and check your crank end play .you should be able to feel the crank knbock as you pull it in and out , if not turn your motor clockwise and counter clockwise and see if it turns smoothly when reversing direction .

Title: Re: Engine "chirps"...MSD
Post by: vwguy on July 18, 2010, 05:17:07 PM

Double check for any main pulley to tin interference, don't rule out a compression leak. double check the cylinder head nuts you can get at, check them for tight.


 Jimmy D

Title: Re: Engine "chirps"...MSD
Post by: blarneyman on July 18, 2010, 05:34:14 PM

Quote from: vwguy on July 18, 2010, 05:17:07 PM

don't rule out a compression leak.
 Jimmy D

Was just going to suggest a compression test. If it sounds like it increases with engine speed it could be something with the valves, rings, heads.....

Title: Re: Engine "chirps"...MSD
Post by: neil68 on July 18, 2010, 09:05:49 PM

Thanks for all the suggestions...I will sort this out.  I'm hoping to race again at both Das Volks on July 30th (Calgary) and at Mission Raceway on August 6th for the DVKK Strip Show.

Title: Re: Engine "chirps"...MSD
Post by: neil68 on July 22, 2010, 08:15:01 PM

Well, the "chirping" turned out to be the 3/4 manifold-to-head gasket...a small piece had pulled up and out, probably when the manifolds came loose while racing last time.  Thanks Geoff, and the rest of DVKK, for your suggestions.

Hope to see you guys at Mission in a couple weeks!!

Title: Re: Engine "chirps"...MSD
Post by: Darren on July 23, 2010, 04:51:44 PM

Sheit, too bad I just read this for the first time... As I was scrolling down the replies I was going to tell you to look for a sucked intake gasket... Glad you found it.  Locktite on the nuts dood!

Loose cam gears rattle at idle,  and loose flywheels cause the front pulley to crack at the hub 99% of the time so those two are easy to spot...

Cheers  K-Roc,