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Hi,

I need to repair or replace the EGR valve on my 88 560. The vacuum actuator part seems fine. It holds a vacuum and I can hear the valve shut when I release the vacuum.

When I did a smoke test, smoke came out of the area in the red circle.

A couple of questions:
1. In order to repair or replace, I need to remove it from the car. Unfortunately I can't get it free of the EGR tube. I can turn it on the tube and move it in and out a few millimeters, but it won't come off. I don't want to use too much force because the tube would be difficult to replace. Any ideas how to get it off? I've tried icing the tube and heating the body of the valve, but that didn't help. It seems the end of the tube is flared a bit.

2. Has anybody repaired one of these and is it possible? A replacement is $200.

Thanks,
Jay
 

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Sorry can't help with the repairs (never had to do one) but keep in mind that your engine is pretty much the same as in the 560SEL/Cs and they are more common in the salvage yards than the SL's. If one is in your area go and see if you can remove the EGR valve. I "practice" on the ones here in Vegas if I am unsure how to do something.
 

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Sorry can't help with the repairs (never had to do one) but keep in mind that your engine is pretty much the same as in the 560SEL/Cs and they are more common in the salvage yards than the SL's. If one is in your area go and see if you can remove the EGR valve. I "practice" on the ones here in Vegas if I am unsure how to do something.
Thanks. I'll give that a try.
 

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The EGR tube is attached to the engine block by two small clips secured with a M10 IIRC. One is near the heat cover of the exhaust manifold the other one at the back of the engine and the bulkhead. A real PIA to remove or install, but by removing them you might have the play to remove the valve itself.
 

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2. Has anybody repaired one of these and is it possible?
I'm new to BenzWorld and also my 560SL, I but had an Audi V6 which occasionally needed EGR maintenance. If the problem is carbon clogging, and not seized or a cracked diaphragm, then you should be able to restore it by cleaning. I let oven cleaner spray soak the inside of the valve, which eventually softens the deposits enough to allow using a wire brush or appropriate picks to do the job, after a washing with water. Don't allow corrosive cleaners onto the diaphragm though. Don't forget to inspect both the exhaust supply pipe and connection to the intake manifold for additional deposits.
 

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Discussion Starter #6
The EGR tube is attached to the engine block by two small clips secured with a M10 IIRC. One is near the heat cover of the exhaust manifold the other one at the back of the engine and the bulkhead. A real PIA to remove or install, but by removing them you might have the play to remove the valve itself.
Thanks for the suggestion. I hope to avoid removing the tube because of the difficulty in access the rear connection. I also haven't seen the tube for sale and don't want to take a chance on breaking it. I'll keep this in mind as a last resort.

Thanks,
Jay
 

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I'm new to BenzWorld and also my 560SL, I but had an Audi V6 which occasionally needed EGR maintenance. If the problem is carbon clogging, and not seized or a cracked diaphragm, then you should be able to restore it by cleaning. I let oven cleaner spray soak the inside of the valve, which eventually softens the deposits enough to allow using a wire brush or appropriate picks to do the job, after a washing with water. Don't allow corrosive cleaners onto the diaphragm though. Don't forget to inspect both the exhaust supply pipe and connection to the intake manifold for additional deposits.
I'll give that a try once I get it off the tube. Hopefully a good cleaning will fix the issue.

Jay
 

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Hi,

I have the same issue like you. Egr holds vaccum and moves inside. But smoke leaks from same place during test. Dont know of that is normal. Any updates on yours. Thanks
 

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I figured out how to get mine disconnected. It didn't have a gasket. I'm not sure why. I put a new gasket on it.

The vacuum part of mine is working fine and not leaking.I believe the gasses that enter the engine from the EGR are metered, so a small leak probably won't affect the engine.

Jay
 

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Hi Spunkmeyer, I might have an alternative suggestion for you.

I think your EGR valve is operating correctly. Especially if the valve is holding vacuum then I frankly wouldn't worry about it.

While I always advocate smoking a vacuum system, remember it is applying positive pressure to components which are used to only negative pressure to expose the leaks.

In this case, since it is the EGR valve you could in theory just plug the vacuum line connection going to the EGR valve. That would certainly solve your leak issue without having to deal with removing, cleaning, or spending money.

Unlike a modern car, this car won't know or care if you disable a component of the emissions system.

On my 380SL, I disabled the clutch on the air pump (but left the belt on it) by disconnecting power to the mechanism. When I got the car smogged, I reconnected it when the engine was hot and disconnected it after the test. It won't run unless the oil temp sensor is below a certain threshold.

It all works and yeah let's save the planet! But why trouble an old car with more things than it needs right?


Anywho, I would disable the component and not worry about it. It's useless to the overall function of the car. Reconnect it for a Concours judge or to pass some overly sensitive smog test.
 
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