News:

The ORG - Truly Independent and Unbiased!

Main Menu

'76 280SE

Started by chrismsullivan, 02 May 2010, 10:10 PM

chrismsullivan

Oh, forgot to mention. I found some sls fluid for $15 a litre. Can't recall the name of the place off hand but will let you all know if you like.

chrismsullivan

Another update!

I've managed to rewire the sunroof switch and motor. After a bit of study, I found the right sequence to attach the wires back to the switch.
At some stage someone has directly wired the power wire to the battery, as it turns out the fuse attached to this wire next to the battery was also blown.
As far as I can ascertain, it looks as though the roof stopped working, probably due to a blown fuse, so they went the hack on the switch...  ???

All of this could have been very easy to fix if I'd known about the rejigged wiring and blown fuse. But alas, simply fault diagnosis lead to removing all of the head lining.

Goodness knows why the motor is in the front of the roof instead of the boot.

I also started to diagnose the misfire/running rich problem. I pulled a plug and yes, it was black and oily, so new plugs and leads will be on the way soon.
I then did the "click" test on the TPS. This was well worth it as it was not smoothly clicking through the "20 clicks" as it should.
So, I removed it, pulled it apart and gave it a bit of a wipe down over the sensor board and the pins.
After reinstalling, the 20 clicks were smooth and very individual.

Time for a test start up.

Presto! Misfire seems to have gone! Hopefully that's all it was. Would correcting the TPS problem aid in helping the car run less rich or is that a separate problem? I haven't had a chance to drive the car after this fix.

I also pulled out the SLS reservoir to confirm that there were no hole in it.. It's all good, but the hose under it was drenched in SLS fluid and underneath that there was about an inch of grease that had accumulated. I presume this is from years and years of a leaking hose.
While it was out I replaced it with a new hose. I know the hose has got to be able to handle mineral oils, but I struggled to find one that was specific to this, so I got a bit of new fuel hose. I though that if the hose can handle fuel, it can surely handle SLS oil??

I'll be picking up some new SLS fluid either tomorrow or Saturday to test if this has cured the leaking problem.

So there you have it. It's nice to see progress on this car, sunroof is fixed, misfire is fixed and SLS is hopefully fixed.

Cheers,
Chris.

KenM

Hey Chris,
                Sounds like you're making good progress there, cleaning the TPS made a big difference eh? My 450SE has a bit of a misfire, have checked plugs and leads etc, so I might try that one next before the trigger points have to come out. It's a learning curve, all good fun. Allegedly.

Cheers,
Ken

oscar

That's awsome Chris.  For a while there I thought the w116 was going to get sidelined in favour of the w108, glad you've come to your senses ;D  Nah, I've always wanted a w108.  Beautiful looking cars, I love the front styling especially and they look so much better in the metal than a photo.  I'd probably prefer a 280se with 3.5L v8 or the 3.5L 300sel w109. But that's not going to happen any time soon.  Garage is full, too many things to do as is and the wallet's too thin.

Anwyay,   I think fuel hose will be fine for the SLS fluid return line.  BTW, what fluid is $15/L and where from.  That's an excellent price.

The TPS can cause a bit of overfueling if it's sending false inputs and if it's clicking during the return-to-closed-throttle motion.  When returning to closed throttle the TPS activates a fuel cut off switch which stops the injectors from injecting.  Anytime you take the foot off the pedal or decelerate the injectors should stop pulsating.  So if you were getting clicks when the throttle was closing then the injectors were still firing when they shouldn't have been.  Whether that was the only cause of rich running....I hope so... but there's other things that could contribute from simple things like blocked air filter, yer dirty plugs and some other things I can't think of right now.  It's great progress for the moment anyhow.

Great to hear you've tackled the sunroof.  I've got no idea about them, never had any in my cars/wrecks so don't know about them nor window motor compatability.



1973 350SE, my first & fave

chrismsullivan

Ken, thanks for the post. I'd say yes to having a look at the TPS before the trigger points.

Turn your ignition on but don't start the car, go to the front and manually activate the accelerator mechanism. You should hear 20 individual clicks when putting the throttle on and none on return. If it sounds all jumbled then that might be one of your problems.

Oscar, thanks again for your post.
The W108 was always going to be a long term project, so it's currently in the garage slowly getting stripped. I too would love a 3.5 or a 109 one day, along with a 190SL. I'll have them
all one day. Oh yes, I'll have them all.
The 116 on the other hand was a good cheap find that I'm growing to love more every day. I always intended to fix it up a bit, register it and then figure out what to do with it. Given that the 108 os going to be such a long project, the 116 is going to stay. 

I'm happy with the progress so far. You're spot on though, the TPS was clocking on and off throttle. I'm glad to hear that this might remedy the car from running rich.
I'm sure the new plugs and an oil change will help too. As far as I can tell from the run it had yesterday, it's runnin nowhere near as lean.

SLS fluid. It's from a place called German Prestige. It's on Geelong Road in Laverton. The fluid itself, don't know what it's called but it's got German writing all over it, has a white bottle and has the mw4 code or something like that. I'm not at home right now so I'm guessing the code from my failing memory. I ended up getting 3 litres for $40.   

oscar

Quote from: chrismsullivan on 14 May 2010, 05:42 PM
SLS fluid. It's from a place called German Prestige. It's on Geelong Road in Laverton. The fluid itself, don't know what it's called but it's got German writing all over it, has a white bottle and has the mw4 code or something like that. I'm not at home right now so I'm guessing the code from my failing memory. I ended up getting 3 litres for $40.   

Thanks for that Chris, that's fantastic.  I've got a few litres of lemfoerder or Febi oil on hand but will source some of this stuff out next time I'm in Vic.

Regarding general tuning and running rich.  Once you get the plugs etc etc sorted it'd be worth having the tailpipe CO measured and if need be, the CO knob adjusted on the ECU in case it's been tampered with in the past.  That can account for some of the rich running.  It's a finnicky thing tuning a d-jet so far as once you adjust one thing it affects other things which need tiny readjustments but no biggie.  You get used to it and find a spot you're happy with.  But issues reappear over time.  You just have to remember what steps you went through to remedy it.  Eg, my TPS was fine for a while but soon it was misbehaving again.  I had to replace with one that had much less use.  Apart from the contacts and wipes wearing and pitting, the two shafts (inner and outer) have to be allowed to move independantly otherwise that cut-off switch doesn't work or works intermittently.  And despite the two shafts slightly contacting each other, I found introducing a liquid lube will eventually make them less independant and the cut off switch falter again.  It should be left dry.  I should've mentioned that before you did the clean in case you did oil it :-\
1973 350SE, my first & fave

chrismsullivan

Just arrived home and checked the brand of the fluid. Yep, it's Febi ZH-M. I've not seen any leaks as yet, so hopefully it's all fixed. Although I did noticed that once I'd topped up the reservoir that there didn't seem to be much flow going through the reservoir. Does it only activate when there's load on the rear or when it's driving?

Once I've done the oil, the plugs, the seat belts and the odometer I'll be taking it in for a RWC and will get the CO reading done then. Thanks fo the tips on that one.

Regarding the TPS. when I pulled it apart I immediately thought that oiling it would not be a good idea given the circuit boatrd in there. So it's all good, I left it nice and dry.

I'll be checking the operation of the TPS pretty regularly from now on, so if it stuffs up again I'll be on the hunt for one in better condition.

chrismsullivan

Hey guys...

I've had a busy few weeks and haven't had a chance to do much to the car, but got stuck into it yesterday.

I've changed the oil, and put in some new plugs. Easy....

Next I thought I'd have a crack at fixing the broken odometer. This was a bit of a mission! After finally getting the instrument cluster out, I went about dismantling the speedo, that was easy enough I suppose, but I'm fairly mechanically minded so it might be more difficult than I'm leading on.
I've read the write up on the fix for the the spindle spinning around but not biting on the cog that actually turns the odometer. I wasn't convinced that a bit of sandpaper and locktite was going to be permanent enough, so I created some ridges on the end of the spindle, with the idea that I'll be able to press fit the spindle into the cog and effectively locking it in place for good.
It was quite difficult reinserting the spindle back into place, but it paid off. I don't think that will be failing again anytime soon.
While the instrument cluster was out I took the opportunity to replace all of the dash and instrument lights given that most of them were blown.

All in all, it was a pretty productive day.... All until I fired her up to ensure that the gauges were all working after removal of the instrument panel.

I noticed that there was quite a bit of fluid dripping from the engine bay onto the ground. The source was the SLS pump on the front of the engine block. Balls. I guess it was just time for it to give way.
I whipped out the allen key and pulled the front of the pump off and found that the seal was cactus. It looked as though some red coloured sealant paste had been used in the past and it had perished. The black oring in there looked OK though.

My question, is there a specific seal or sealent paste I should use in order to plug this leak?

Cheers,
Chris

GreaseMonkey

Get a seal kit from MB Spares to rebuild the pump. No point in trying to use a sealant when the full kit of seals costs (I seem to remember from last year) $45. If you have the pump apart why bodge it and risk having to do it again.
Apart from that, I have enjoyed reading your thread and the progress on your car. I am currently without a W116 but reading this has made me want to get another.
Chris M.

chrismsullivan

Hi Chris,

Thanks for the tip with obtaining a kit from MBSpares. It's good to know that there is actually a kit and I didn't have to do a bodgy fix.

I'll follow it up with them.

Glad you're enjoying the thread.

chrismsullivan

Just confirmed with MBSpares via email that the SLS seal kit is $99. Still to speak to them, so don't know if that includes postage or not.

Chris.

oscar

Congrats on the odometer, it's a prick of a job, especially if a fix like mine doesn't work.  Knurling the spindle I've thought would be the best way to go and you've done something similar.  The ridges should hold that sucker on for good hopefully.

About the pump, there's a few good threads on rebuilding them so have a search but check out koan's gallery pics on a pump stripdown.  I've only resealed one pump but neglected a rear casing seal which I never knew existed until koan's stripdown.
http://gallery.w116.org/v/garage/koan/suspension_pump/1
1973 350SE, my first & fave

chrismsullivan

Thanks Oscar. Yep, the odeometer was a prick of a job. I'm dying to actually go out and drive the car to ensure that the odemeter is working properly. The leaking SLS pump put an end to that!

So far I've only take the front of the pump off the front of the block and haven't investigated removing the whole pump as yet.
Is it a difficult task or is it just bolted on there?

Cheers,
Chris

oscar

Nah not difficult at all especially on the 280 because it's so easy to get at. 

Some things to watch out for anyone;
- Like any allen bolts, these can be rounded if not treated with care and the correct allen size used (5mm I think). 
- Use a flare wrench to undo the supply line if possible otherwise it can distort. 
- Note there's two copper washers for the high pressure outlet, one either side of the banjo fitting.
- Lastly, when you pull the pump from the engine you should keep an eye out for a round coupling pictured below above the two pumps.  It was only by chance I found mine on the floor at a time when I didn't know they existed.

If you've taken the front cover off you've probably noticed that of the 6 allen bolts, 2 hold the front cover on and 4 hold the body of the pump to the engine.  But those 4 longer bolts also hold the cover on so I'm assuming the only thing holding your pump to the engine at the moment is the adhesion of the gasket.  Before removing the lines I'd put the cover back on and secure the long bolts again otherwise the pump will pry off the engine the moment you try to undo one of the lines making them really difficult to undo.

1973 350SE, my first & fave

chrismsullivan

Awesome.. That's great information. Thanks Oscar.