The pump has nothing to do with that block

Pump controls C/L
Engine Vacuum controls climate control flaps.

 

I respectfully disagree. The pump delivers vacuum to the block in a separate line, in case the engine manifold does not produce enough vacuum for the climate controls to operate properly. They are linked together by a clear hose. So if the pump detects a small leak, either from the central locking OR the manifold connections, it will cycle on 2-3 seconds every 15-17 seconds. It will do so 31 times before it stops (built in protection).

The clear line has the marking PU (vacuum for aux consumers for supporting the intake manifold vacuum). It's all there in section 80-010 - Function description of central locking in the repair manual.

 

You're right, I'm wrong.

Everyday is a school day, sorry for jumping in like that.

 

The sad truth is your block didn't just split, it's been split for a very long time and a new block will split shortly.

Your best course of action is to merely repair the split (unless the ball has actually fallen out) with gasket sealer.

A new valve block will split within a year and you will be back to square one.

 

Surely they have JBWeld in the Nordic countries?

JB Weld | World's Strongest Bond

Maybe we need to send a care package?

Dan

 

Really?! I'll keep a close look.

If this is the case, the vacuum pump issue is unrelated to a cracked manifold. Have to investigate further, I guess.


Sent from AutoGuide.com Free App

 

Wow, just replaced mine and....HOLY F!

I've been steadily replacing most of the soft parts in the engine bay that could cause a vacuum leak, and with every old, cracked, and leaky hose I've replaced the engine has gotten better, but since replacing the vacuum block, the car is on another level in power and responsiveness. Kinda amazing actually. Before, I'd have to leave the car in 4th gear to feel like I could get satisfying response and power around town. Now, I leave it in 5th and it feels more powerful and responsive than how it felt before in 4th. The exhaust is clearly rortier, the brake pedal is firmer and has better overall feel, and the transmission shifts faster and more smoothly. A-freaking-mazing.

 

Glad you got improvement, but you've must had a very significant vacuum leak in the manifold to get these effects. Mine was cracked (barely visible), but no effect on either pump or running conditions.

 

Thanks man! However, my cracked dist block looked exactly like yours. So, maybe it's a difference in engines with mine being a 99 with the m113 engine? Or perhaps you have some more unidentified vacuum leaks? Hopefully the former, and not the latter. As far as I can tell, I've now replaced every hose, seal, or gasket in or somehow connected to the intake tract and it's running better than I thought the portly beast ever could.

 

So is the ball supposed to be able to move, or is it fixed in there and we can just JB Weld away on the crack..

Because, as you can guess, I just pulled mine, just to see, and guess what? Mine's cracked too! LOL

So yeah, looks like it's an easy fix, but just want to make sure I'm not stopping the metal ball from moving, if it's supposed to..
It's not moving on mine, but just want to verify that is correct...

Thanks!

 

As stated in post # 7, JB Weld is a good fix

 

Sounds good.... Thanks....and already done..

Used the 6-minute (set-up time) JB-Weld, applied a liberal amount to help beef-up the area a bit, including the ball.. And once set, carefully put it back in place and put the single bolt back in.. Done!!
ALL jobs should be so easy.. ;-)

Thanks again for this thread.. I wouldn't have looked if not for this. My vents worked "pretty good", but not impressive in any way.. I'll be driving it tomorrow (JB-Weld will have fully cured by then) so we'll see if any improvement..

It wasn't a huge crack, but I'm sure ~any~ vacuum leak solved is a good thing for engine performance as well, so it's a win-win!

Barry

 

After driving about 25 miles yesterday, two things come to mind..

First, the HVAC vents seem to be a little more consistent, but nothing earth-shattering. They were working respectably before the fix, but I'm not sure that the early morning 12 miles was enough of a test...
I drove back home with the top down, the weather was perfect! So no HVAC needed for half the trip...

Second, and (to me) more importantly, I don't think the engine has ever run smoother than it did yesterday...
Very responsive, and ran strong.. I'm not saying it was like night and day, because it was running good before...
But think it's now running and accelerating more smoothly than it ever has... Happy, happy!

So, bottom line, for ANYONE with an R129, DO CHECK your vacuum distribution block.

It's an easy 1-screw (8mm socket, I believe, 1/4" ratchet) removal, and then just pivot up the block to see if it's cracked. You don't need to disconnect any lines (unless you see a problem there too), but just gently lift up on the block to inspect...
If you see the small split, just use a little JB-Weld on the crack and end, let it set, and re-mount the block when dry...
It's EASY, and WORTH IT!

Thanks again for this great thread, and this website as a GREAT resource for keep these cars running..

Barry

 

Nice.

My cracked dist block looked like pictures of every cracked one I've seen on the internet, and I could see it pretty easily by shining a flashlight at it. Kinda strange I've read several accounts of people saying it is not visible without removing the block.

 

I can see what you're saying, it's certainly visible, if it's a good-sized crack, and you know exactly what you're looking for...

Just mentioning that it's even more obvious if you remove the screw and look at the block if it's in a more horizontal position...

Either way, if it's cracked, one of the easiest and cheapest things you'll fix on your car, on a bang-for-buck basis.....

 

Guys,

You are most awesome!! Just found this on my newly acquired 1995 C220, thanks to your posts.

Was wondering why a motor in the right rear quarter was cycling. Also my center A/C vents would only function intermittently. Trans also seemed to have an occasional 2-3 shifting inconsistency, not sure if that's related.

About to attempt removal and sealing with J-B Weld. Film at 11 - will post how it turns out!

Edit: So far so good - applied and letting it dry.

Edit of Edit: Amazing - car seems to run better, door locks are more responsive, and the transmission shifts seem better too. Holding the key in the drivers door lock now drops and closes the windows. And no more whirring from the back deck area.

Now if I can find away to reset my SRS light from having had the dash out (not related to the vacuum leak), will be all set.


--------------
Paul Patti
Nashua, NH

1995 C220 - Imperial Red (traded 2000)
2000 C230 Kompressor Sport - Brilliant Silver Metallic (sold 2006)
1995 C220 - Imperial Red (forever!)

 

Okay, I saw this thread and thought I would investigate. Where exactly is it? I looked on the passenger side but I don't readily see it. Anyone got a picture of the location?

UPDATE: Found it. If it was a snake it would have bit me….
:wink

 

Daniel, no worries! I'm still getting used to where things are on this new-to-me 1995 C220 as well. It's been 17 years since I traded the one I shouldn't have sold! Now am working to get this one into pristine condition. Good luck with your SL!

 

Not quite a threadus ressurectus, but I can relate... I just completed a 800 mile trip in the r129 and noted at times, my center vents were a bit weak. having read about this vacuum block cracking some time ago, i decided to have a look at mine (it looked just like the picture leading this thread). having some permatex ultra-black gasket maker, I spread a bit liberally across the end and the crack. we'll see if there is any difference next outing.

Incidentally, only 4 lines attach to the block in my '97; a green, red, white, and kinda translucent line. I did not remove but just took the bolt loose and turned up to dab the gasket maker, so I can't say for sure the other ports are blocked (must be...). there are no lines laying loose or empty connectors in the block.

 

There are only the 4 lines as you described.

These three are mounted in a row together at the base of the block:

1. Red for the vacuum reservoir in the passenger side fender.
2. Clear-ish goes to the trunk mounted vacuum pump.
3. Green for the Y11 block.

The top center port is for the white/light gray line leading to the intake manifold.

All the ports are self sealing when not in use.

 

I checked mine last night and it was cracked. So a little JB Weld. I'll drive some tonight to see how it does.

 

My 95 has 6 lines and yes it was cracked in the same place. Epoxy is your friend.

 

I wonder where the 2 black lines go on your car?

 

Update: SRS light was finally reset a few months ago. Indy tech with a really old scanner made it happen. Now I will never forget to disconnect my negative battery cable before doing dash or steering column work!

 

Great information here, I'd definitely going to check it out! Recently noticed that the center vent's are lazy, even with "clicking" sound at times under passenger side bolster, time to check this block for cracks and Y11 I guess?

Regards,
D

 

D, yes - sounds like a good idea to check. My rear (trunk) vacuum pump still actuates every now and then, but nowhere near as often as it used to before I replaced the vacuum block. Good luck to you & plz let us know how it goes!

 

Going to check mine too.
Just a note on the part number:
up to end of MY '96 129-800-14-78
MY '97 and up part 129-800-31-78

I can't seem to find my vacuum block (MY2000 SL500). On WIS all I could find was how to diagnose problems, no remove/replace instructions or location. Any help on this one?
Thanks!
Peter.

 

Found it, and also the 8mm attachment screw, partially concealed on the engine side of the firewall, behind an offset hole in the sound deadening felt, and yes, it is cracked (see picture).
Question: Does the ball need to move, do I epoxy all over the crack and the end of the exposed ball, or just the crack?