603 Vac Pump post shut-down ticking - PeachParts Mercedes-Benz Forum

87tdwagen · #1 02-09-2006, 09:49 PM

Hello all:

I've noticed for a while a post shut-down ticking noise eminating from the front of my 603. I never thought much of it until today as I was probing around with my steth and determined that the ticking is coming from the vac pump. Reason unknown???

The ticking is steady once every three seconds and stays until the engine cools down a bit say for 20 minutes. Any ideas? Should I be concerned? This is a new style pump and has less than 10k mi on it

Thanks

Diesel Giant · #2 02-09-2006, 10:31 PM

That is very strange. I have never heard of such an anomoly.

87tdwagen · #3 02-09-2006, 10:45 PM

Quote:

Originally Posted by Diesel Giant

That is very strange. I have never heard of such an anomoly.

I was thinking that maybe there is a vacuum release mechanism, it sounds like a pindle valve in a thermostat tick...tick...tick

I hope this thing isn't some time bomb

Anyone else noticed this??

WVOtoGO · #4 02-09-2006, 10:55 PM

Funny you should bring this up. Just yesterday I was under the hood right after shutdown and noticed a noise from my pump as well. It’s about every 5 to 10 seconds with mine. I wouldn’t call it a tick, but more of a quick (1/8 sec.) squeak. It sounded to me like a vacuum leak in 1/8 second hits. It got my attention because it was so odd of a sound. Almost like some video game space gun sound effect.
Thanks for bringing it up. I hope we can solve this one.

87tdwagen · #5 02-10-2006, 03:51 PM

Quote:

Originally Posted by WVOtoGO

Funny you should bring this up. Just yesterday I was under the hood right after shutdown and noticed a noise from my pump as well. It’s about every 5 to 10 seconds with mine. I wouldn’t call it a tick, but more of a quick (1/8 sec.) squeak. It sounded to me like a vacuum leak in 1/8 second hits. It got my attention because it was so odd of a sound. Almost like some video game space gun sound effect.
Thanks for bringing it up. I hope we can solve this one.

Although mine is faster and sounds like a squick

I just checked it again and feel and hear it more on the thick vac line that comes from the vac pump. The noise is loudest from the pump and weaker along the vac line.

Does anyone know if this is a leak in the pump? due to heat? normal?

Thanks

Diesel Giant · #6 02-10-2006, 07:38 PM

Ok that may be a clue. Now that I think about it, it could be vacuum bleeding off, but I would not think it would make a ticking sound.

WVOtoGO · #7 02-10-2006, 11:31 PM

Quote:

Originally Posted by Diesel Giant

Ok that may be a clue. Now that I think about it, it could be vacuum bleeding off, but I would not think it would make a ticking sound.

Mine is definitely vacuum bleeding off. In very short little squirts (or I guess maybe sucks). My question now is: Is this normal? I don’t recall ever hearing it over the past 25 years, so perhaps not. I did just rebuild my vacuum pump last year though. Hope I did it right.

87tdwagen · #8 02-11-2006, 12:19 PM

Quote:

Originally Posted by WVOtoGO

Mine is definitely vacuum bleeding off. In very short little squirts (or I guess maybe sucks). My question now is: Is this normal? I don’t recall ever hearing it over the past 25 years, so perhaps not. I did just rebuild my vacuum pump last year though. Hope I did it right.

To quote above: Is this normal??? I have searched the archieves and have not seen article regarding vac pump noises post-shut-down, only bad noises leading to major bad stuff.

This pump is new style and has less than 10 k miles

POLL:
1. Does your vac pump make a repetitious noise after shut down as described in preceeding posts?

2. Do you have the old or new style vac pump (might be a design difference)

Thanks,
Bill