removing emissions grey car 126 - PeachParts Mercedes-Benz Forum

126nut · #1 02-12-2012, 10:07 PM

On my 83 500 SEC

No emissions testing here on old stuff so guess this is not illegal, good thing about driving an antique I suppose. I took off the cats but still have the goofy air pump. Would be easy to lose it but there is a hose connected to a check valve on the side of the front cover. Guess this is where it sucks crankcase vapors off the block. Not sure how to deal with it, plug it off with a rubber cap like they use on waterpump nipples?

Not sure what the Euro car originally had there.

Thanks

Hit Man X · #2 02-13-2012, 02:19 AM

Air pump is easy to remove. Just pull the alternator and start unbolting it. Takes about an hour to remove the air pump with its bracket. The check valve to the head... I just filled mine with high temp RTV, no problems.

The check valve is what pumps 'air' from the 'air pump'

into the exhaust ports to aid in cold starts due to the inefficiency of the CIS system.

EGR is easy to unplug, but a pain to fully delete as the intake plenum requires removal. Just pull the pipe and cut a block off plate out of some metal stock.

If you also have all the hard vac hoses at the throttle body, most of these are just for nonsense to activate the two temp switches with the two tits... one is for EGR and other for the charcoal canister. All of that can be removed too. the canister is under the driver fender liner if you have it.

126nut · #3 02-13-2012, 09:35 AM

Yes there is a bunch of crap hoses going everywhere but from what I hear the only one that means anything is the vacuum advance. I used to worry a lot about getting them all connected but from what I hear you can get rid of almost all of them with no ill effect.

Forgot about the steel tube egr line going to the lower plenum, I would give anything almost to see what this car looked like under the hood before it was hacked up with the EPA mandated stuff in order to get it legal. Did Euro cars come with EGR's and the check valve on the side of the front cover? If you RTV'd yours shut then what was there before the car was smogged?

Oh yeah and I used to have a 500 SEL 85 model that had way more guts than this 83 model. Any thoughts on engine comparisons or should they have been pretty much identical?

Hit Man X · #4 02-20-2012, 03:41 AM

Quote:

Originally Posted by 126nut

Yes there is a bunch of crap hoses going everywhere but from what I hear the only one that means anything is the vacuum advance. I used to worry a lot about getting them all connected but from what I hear you can get rid of almost all of them with no ill effect.

Forgot about the steel tube egr line going to the lower plenum, I would give anything almost to see what this car looked like under the hood before it was hacked up with the EPA mandated stuff in order to get it legal. Did Euro cars come with EGR's and the check valve on the side of the front cover? If you RTV'd yours shut then what was there before the car was smogged?

Oh yeah and I used to have a 500 SEL 85 model that had way more guts than this 83 model. Any thoughts on engine comparisons or should they have been pretty much identical?

Pretty much as you said, just the vacuum advance is all that is really needed. The rest of the 'spaghetti' can be removed. I have my 300SEL gutted to just the basics also... HVAC and vacuum advance only. Car passed the sniffer big time last month.

Yes, ECE cars also had the EGR business. My '80 380SE had vac pump and the check valve on the passenger head.

I had the AIR pump (cold start only use) on the M117. I just removed it all as the pump was bad. Since the check valve is threaded, I just cleaned it up well then filled it with high temp RTV. The check valve on the M103 is held in with a cap screw so I just had the machine shop install a freeze plug in that location. Hell you could even weld it shut or epoxy it shut depending on how you felt.

As I understand the 'Euro' 5L had about the same HP as the US 560... around 240hp. You could have late camshafts, vacuum leaks, misadjusted CIS system, wrong base timing, low compression, etc.

Bondavi · #5 02-21-2012, 05:07 AM

There is a 3/2 valve at the inner plenum where the butterfly valve is. Full WOT enrichment depends on this so as said above, remove the spaghetti of non essential lines and use the PDF to re construct your vacuum system.

Best of luck!

126nut · #6 02-22-2012, 10:04 AM

Is that valve a plastic thing that screws onto the linkage side of the butterfly? Like you say it looks to only do anything at WOT. I did replace it, after putting the car all back together and it was a real pain to get at. I would have done it sooner but had trouble finding it anywhere, finally got the part number off Benzworld site. Sorry but lot's of good info over there.

Where is the PDF you are referring to as my CD doesn't show vacuum schematics having anything to do with my Euro car. Actually all my schematics show a throttle switch or TPS on the butterfly, something my car does not have.