New "Tour" of engine setup/tuning added to Tech Manual

[twistedtree]

I created a new "tour" in the Tech Manual covering the steps involved in a start to finish setup/tune-up of a pagoda.  Comments. questions, corrections are encouraged.  Others know this stuff way better than I do - I'm just trying to capture it.

One particular thing I'd like to get thoughts on is where to place this tour in the Tech Manual.  It doesn't really fit under any of the car components, so I put it a little lower down where there are a few other miscellaneous topics.  I'm not real please with it's location, but don't have a better idea at this point.

[Peter van Es]

Well done... I think it is in a fine place. The reason the other tours are in the Restricted section is that then only Full Members can access them...

If anyone has suggestions for a different place, I can move it there easily.

Peter

[twistedtree]

I don't think it should go in the restricted area.  The tuneup tour is a likely stopping point for newcomers, and it includes several links to the restricted content which hopefully will provide incentive for people to become full members.

[Naj ✝︎]

Hello, Peter(s)

Can you add a link here; I can't seem to find it.

But then, its Sunday...

Naj

[Peter van Es]

http://www.sl113.org/wiki/TuneupOverview/Start

[twistedtree]

On the main page under "Contents", there is a small grouping of topics near the end that includes "buying a car", "documentation", "suppliers", etc.  The link is there.

And here's a direct link http://www.sl113.org/wiki/TuneupOverview/Start

The fact that you couldn't find it suggests it's not in the best spot.

[ja17]

Hello Peter,
I noticed that the compression check is taken after the head bolt re-torque. In this case you may want to change sequence or  give a warning that taking the compression check with the valve cover off will result in huge oil loss! Doing the compression check on a warm engine is my preference. Also after the valve adjustment is best also. General tuning should follow. Not sure if we can avoid some repetition.

Also, the spark plug wires and resistor ends are not matched to the coil, but are checked for condition and resistance. You may want to include "prepare to replace the valve cover gasket if it has become brittle and hard".  If breaks or cracks after bending it sharply, it should be replaced.
*Replacement wires, condensors etc. may not look like the originals. *If you are concerned about originality, you may want to research this or source NOS.

I had trouble finding it also.

Looks good so far,
Thanks,

Joe

[Peter van Es]

I've added some more links (not just from the home page, but also from the Engine page, the Maintenance page and the Full Member tours only). It should be easier to find it now.

[twistedtree]

Joe, I made changes to reflect your comments.  I've also found myself chasing vacuum leaks today while trying to get one car running right, so I added that step too.

[ja17]

Hello Peter,
some more ramblings on tuning, use what you  like..................

"cold engine idle at start up" should be 1000rpm, as you mention

Vacuum is not usually used in engine tuning these days but more a troubleshooting tool. Modern engines defeat natural engine vacuum readings by unnaturally changing engine ignition timing.

There is an "ignition change over switch" on the later W113 engines (located on the thermostat housing). It modifies ignition timing at certain times for emission purposes.

The W113 engine distributors had either an ignition advance or an ignition retard, depending on the engine year and distributor used.  

Later W113 cars came equipped with a factory electronic ignition. Check to see if your (1969 or later) engine is equipped with it. It is located under the battery tray. If it has been eliminated a different coil and ballast resistor configuration would be required.

Perform a "Split Linkage Test" or a CO meter test to determine the fuel mixture and adjust the injection as needed.

Test Drive to check for engine strength and smoothness. Also check the transmission smoothness and shift points. Check smooth downshift at stop and check for kickdown (passing gear).

Most of the time a tune up includes a lube service.............change oil when the engine is hot.  Drain the oil cooler if your car is a 280SL.  !!! Always check for the upper filter sea, in the engine. Use a good quality approved oil filter. Some aftermarket brands are inferior and slightly shorter.
Re-install  the drain plug tight. Add fresh oil. (6-7.5 qts , varies depending on engine type and year)

[twistedtree]

Joe, thanks.  I'll make further tweaks to the text.

There's one thing I'd like to cross check to see if others agree, and be sure the intent is clear in the tour.  I envisioned the tour serving people going through what I've been dealing with, namely a car that runs (maybe just basely), but where you otherwise have no clue what's working and what's not.  In fact you expect plenty is not working and need to get it all sorted out.  It could be a barn find that you just got started, or a car coming out of a long hibernation.  Or even a car you just bought and need to figure out where it stands.

I do not envision it as a general tune up guide for dialing in a car that's been running fine.  Nor do I see it as a periodic maintenance and tune up guide.  There are other sections that address some or all of those topics.

It also is not intended to be a guide for raising a car from the dead.  In not sure if there is a tour for that, but there is plenty of discussion material in the forums.  Maybe a tour would be good to write at some point, but it's not what I had in mind for this one.

The other thought was to reference existing material as much as possible rather than repeat it.  So for example it references the linkage tour and FIP sections and simply says to make sure the linkages are correct and that the mixture is correct.  That's a big hand-wave, but I think works given the content of the other tours.  In many ways it makes this a tour of tours, and just guides the reader through the other sections in a logical order given where I think they are starting from.

So the questions are:

1) is this the right approach

2) is it clear from the tour who it's intended for, that you need to spend time in the referenced sections, and is it clear what the tour is not intended to be.  Personally I'm thinking I could beef it up in this respect.

[Iconic]

Nice writeup Peter.
I have two comments/questions.
1. I would suggest adding a line similar to the following at the end of the first paragraph: "This tour does not include regular maintenance items. This tour is for the purpose of getting an engine running correctly.". I realize it is redundant, but if you are concerned about making sure the intent is known, it drives the idea home at the end of the introduction.
2. "Confirm operation of dash pots (which ones, and where are they?) ." Do we really have dash pots on our Pagodes???

Mark

[Benz Dr.]

I would add a couple of things:
While doing a compression test, remove fuse number 4. This will prevent the CSV from spraying any fuel into the intake manifold and washing down the cylinders.

The thermo switch on the thermostat housing isn't for polution control and is there to advance the ignition timing under 2,200 RPM at engine temps above 100C. Late timing will make your engine run hotter.

[66andBlue]

... The thermo switch on the thermostat housing isn't for polution control and is there to advance the ignition timing under 2,200 RPM at engine temps above 100C. ...

Oh good doctor, you lost me. Can you explain why?

[ja17]

Yes I agree Dan, the switch actually cancels the emission retard timing, so the engine will cool. You could you say it is an "anti-emission control" ?

[Benz Dr.]

Yes I agree Dan, the switch actually cancels the emission retard timing, so the engine will cool. You could you say it is an "anti-emission control" ?

That's how it works Joe.

  Removing the fuse for the fuel pump shuts of any fuel going to the CSV. You don't want fuel spraying out of there while doing compresion testing or any other operation where you are spining the engine over without any ignition. All of that fuel will eventually wash down the cylinder walls and you won't have a very acurate compression test. If the CSV happens to be leaking you will really have a lot of fuel in the clyinders.
It would be like pumping the gas pedal while you have the coil wire of an engine with a carb. Eventually you are going to flood the engine.

[twistedtree]

Thanks Dan, that's an excellent tip.  I think I'll add it to the section on doing a compression test.