Andrew280SEL
New Member
Hi guys,
I figured I might give a bit of an update of where I am with my two W116's, since I've been inactive for quite a while before coming back on last week.
Those of you from the ORG site may remember that my 560,000 km 280SEL, while a beautiful car in appearance, had a couple of annoying mechanical problems.
Mainly because it was a dog to start when warm, and because of a bad vacuum leak somewhere in the inlet manifold, idled terribly under load (i.e in gear). Not to mention the terrible fuel fumes as it ran incredibly rich at the same time.
Now it was only recently I got around to being able to do any actual work on the cars, so the week before last I acquired some new K-Jet fuel injectors and seals for the 280.
The old injectors were very suspect seeing as the car ran so rich and started terribly warm, so naturally I was expecting a big improvement after installing them.
I've never done an injector job on these or any cars before, but the K-Jet job is surprisingly simple and easy.
So anyway I installed the new injectors, and after doing all the checks for fuel leaks and making sure everything was fine, I took it for a spin to town.
As I said, I expected a big improvement, and sure enough there was.
Despite still having a bit of a dodgy idle under load while "crawling" (i.e moving into a parking space) due to the vacuum problem, the car starts FIRST time EVERY time now, no matter what temp
The reliable instant starting is something I'm glad to have back! It's starts beautifully and general response and smoothness with acceleration is noticeably better. I wish I could have gotten around to doing the injectors sooner, but I'm happy now in any case. The fumes are also gone.
The vacuum leak is still something I have to do, and unfortunately I may have to remove the inlet manifold which I'm certain is gonna be significantly more time consuming.
However, my next job with the 280 is to remove the old exhaust manifold "Y-piece" which has cracked (as they all do...) and replace it with a new W123 piece that I've bought. That way it will be a bit quieter
As for my 350SE...
Well for starters, it seemed the timing was moving around and I was getting inconsistent performance. As expected, the distributor had bad vertical movement in the shaft. Thankfully, I had a good distributor sitting in a 450SE (they seem to be interchangeable like many parts with the M116 and M117 motor) parts car which I swapped over to mine a month or so ago. Had to get the timing re-done as I struggled to do it myself, despite having a timing light I had trouble not only interpreting the marks on the crankshaft pulley, but seeing all the way down there in the first place...
That had a nice improvement also, in power. The only strange thing is, after installing the new distributor, the fast idle, which never originally worked on this car, started working again. But this time it never goes off even when warmed up! So my thoughts are that the Air Slide had "somehow" come unstuck when I changed distributors (no idea how though!) and then stuck in the opposite position (open)
Well, that's the theory. So I'm going to have to remove it and try to free it up. Basically, the car will always idle around 1500 or so even with the idle screw all the way down unless I remove the Air Temperature Sensor (T1) on the air cleaner snorkel, which brings the idle right down to a normal level. For the time being, I have the T1 connector disconnected. Hopefully that has little effect on performance.
So that's one little job to do.
I also suspect the MPS needs replacing, as performance around 20-60 km/h driving around town the performance is a little inconsistent and hesitant in response. Well basically there's no smooth transition between certain revs. Thanks to Oscar and his previous threads for helping to understand this
I'll need to test the MPS first obviously, but I highly suspect it seeing as the symptoms fit perfectly.
The only other thing is, until I get the valve stem seals done, cylinder 3 and 6 tend to oil foul their respective spark plugs. The rest of the plugs are fine, but those two need cleaning every so often.
Other than those mechanical fixes/problems, I've done a little tidy up with the 350's appearance. So I've got some pics here to show. I don't have any of the 280SEL unfortunately, as it's locked up and covered in the garage at the moment and it's wheel trims are getting repainted currently at the bodyworks.
So here's my 350SE. It looks ALOT better than the neglected $800 car I originally purchased, in my opinion. Amazing what some TLC and a reasonably small amount of money (SS wheel arch trims, touch up paint etc) can do
Excuse dodgy camera phone lighting...
Excuse the dodgy Milan Brown paint making it's way into the photo..
The 350 will, however, in time receive a full new paint job as the bonnet and a few other areas are cracked and well, not good. When that happens, the spoiler from Styria will be fitted and painted.
Don't want the lovely spoiler showing up the poor front of the car, the way it is currently
FYI Styria, the second spoiler we have has been placed on the supposed track car, the manual 280SE, though it's not painted yet.
I figured I might give a bit of an update of where I am with my two W116's, since I've been inactive for quite a while before coming back on last week.
Those of you from the ORG site may remember that my 560,000 km 280SEL, while a beautiful car in appearance, had a couple of annoying mechanical problems.
Mainly because it was a dog to start when warm, and because of a bad vacuum leak somewhere in the inlet manifold, idled terribly under load (i.e in gear). Not to mention the terrible fuel fumes as it ran incredibly rich at the same time.
Now it was only recently I got around to being able to do any actual work on the cars, so the week before last I acquired some new K-Jet fuel injectors and seals for the 280.
The old injectors were very suspect seeing as the car ran so rich and started terribly warm, so naturally I was expecting a big improvement after installing them.
I've never done an injector job on these or any cars before, but the K-Jet job is surprisingly simple and easy.
So anyway I installed the new injectors, and after doing all the checks for fuel leaks and making sure everything was fine, I took it for a spin to town.
As I said, I expected a big improvement, and sure enough there was.
Despite still having a bit of a dodgy idle under load while "crawling" (i.e moving into a parking space) due to the vacuum problem, the car starts FIRST time EVERY time now, no matter what temp
The reliable instant starting is something I'm glad to have back! It's starts beautifully and general response and smoothness with acceleration is noticeably better. I wish I could have gotten around to doing the injectors sooner, but I'm happy now in any case. The fumes are also gone.
The vacuum leak is still something I have to do, and unfortunately I may have to remove the inlet manifold which I'm certain is gonna be significantly more time consuming.
However, my next job with the 280 is to remove the old exhaust manifold "Y-piece" which has cracked (as they all do...) and replace it with a new W123 piece that I've bought. That way it will be a bit quieter
As for my 350SE...
Well for starters, it seemed the timing was moving around and I was getting inconsistent performance. As expected, the distributor had bad vertical movement in the shaft. Thankfully, I had a good distributor sitting in a 450SE (they seem to be interchangeable like many parts with the M116 and M117 motor) parts car which I swapped over to mine a month or so ago. Had to get the timing re-done as I struggled to do it myself, despite having a timing light I had trouble not only interpreting the marks on the crankshaft pulley, but seeing all the way down there in the first place...
That had a nice improvement also, in power. The only strange thing is, after installing the new distributor, the fast idle, which never originally worked on this car, started working again. But this time it never goes off even when warmed up! So my thoughts are that the Air Slide had "somehow" come unstuck when I changed distributors (no idea how though!) and then stuck in the opposite position (open)
Well, that's the theory. So I'm going to have to remove it and try to free it up. Basically, the car will always idle around 1500 or so even with the idle screw all the way down unless I remove the Air Temperature Sensor (T1) on the air cleaner snorkel, which brings the idle right down to a normal level. For the time being, I have the T1 connector disconnected. Hopefully that has little effect on performance.
So that's one little job to do.
I also suspect the MPS needs replacing, as performance around 20-60 km/h driving around town the performance is a little inconsistent and hesitant in response. Well basically there's no smooth transition between certain revs. Thanks to Oscar and his previous threads for helping to understand this
I'll need to test the MPS first obviously, but I highly suspect it seeing as the symptoms fit perfectly.
The only other thing is, until I get the valve stem seals done, cylinder 3 and 6 tend to oil foul their respective spark plugs. The rest of the plugs are fine, but those two need cleaning every so often.
Other than those mechanical fixes/problems, I've done a little tidy up with the 350's appearance. So I've got some pics here to show. I don't have any of the 280SEL unfortunately, as it's locked up and covered in the garage at the moment and it's wheel trims are getting repainted currently at the bodyworks.
So here's my 350SE. It looks ALOT better than the neglected $800 car I originally purchased, in my opinion. Amazing what some TLC and a reasonably small amount of money (SS wheel arch trims, touch up paint etc) can do
Excuse dodgy camera phone lighting...
Excuse the dodgy Milan Brown paint making it's way into the photo..
The 350 will, however, in time receive a full new paint job as the bonnet and a few other areas are cracked and well, not good. When that happens, the spoiler from Styria will be fitted and painted.
Don't want the lovely spoiler showing up the poor front of the car, the way it is currently
FYI Styria, the second spoiler we have has been placed on the supposed track car, the manual 280SE, though it's not painted yet.
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