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Posted by: BK911 Sep 15 2017, 06:19 PM

Ok guys, not sure what to do.
Recent acquisition of a '76 912E #483.
As most of you know, it is powered by a 914 2.0 with Ljet induction.
Motor runs well, but idles high and runs warmer than expected, so I am thinking vacuum leak.
Of course will go through ignition first, since 90% of FI problems are ignition.
Chased FI problems on my 1.7 djet for a couple years before I gave up and put on some EMPIs.
Been running awesome for years now!
So....
Thinking of spending a couple of hours tuning the ljet and replacing all vac lines, but also thinking of just taking the plunge and putting on some EMPIs.
Thoughts ?
Don't care about resale; car is going in dd rotation and will get DRIVEN!!

Posted by: ndfrigi Sep 15 2017, 06:35 PM

When I fixed 2 1.8FI for my 75 and for a friend's 74, I didn't use any smoke machine. Well maybe a lot easier for ljet but with our '02 MB C-240, took me months to fix some OBDii error codes and pertaining various parts including vacuum leak. I ended up buying a less than $100 smoke machine 2 weeks ago. And just an hour, i found the culprit of the error code and its just a small vacuum tube.

Posted by: ndfrigi Sep 15 2017, 06:40 PM

not sure if you will notice the white smoke just below the glove i used to cover the trottle body.

Posted by: Chris H. Sep 15 2017, 08:29 PM

You're probably right on the vacuum leak. L-Jet is much more finicky and intolerant of vacuum leaks. Even if it's not the main issue or the only issue, replacing any seals or hoses that look suspect will improve performance. I clamped all the hoses on mine and it helped. There is also a rubber boot that sometimes cracks. You can spray it with that plastic-dip stuff.

Posted by: Mikey914 Sep 16 2017, 07:42 AM

My wife's is run on stock F/I, runs like a champ. Your efforts will be rewarded. Many of these have been converted to carbs.we can get 30mpg on the freeway, making these cars very economical and also fun to drive.

Posted by: Krieger Sep 16 2017, 07:47 AM

Don't forget to look at the two oil filler cap seals as well as the gasket the assembly sits on.

Posted by: BK911 Sep 16 2017, 10:34 AM

Thanks guys, heading to garage now.
Will try to fix first, but really leaning towards the carbs.

Posted by: r_towle Sep 16 2017, 10:43 AM

Running too hot may mean your timing was advanced too much to mask the vacuum leak. Ljet is very simple, it works or it does not. Replace all the vacuum lines, oil cover seals and check the plenum for leaks, and the manifold to head connection for leaks.
Replace the injector seals.

Timing,
Clean your distributor advance plates, get rid of the 40 year old grease, it's like glue when hot. That will also make carbs run like crap. Set the timing per the book specs. If you can't keep it running with the timing set properly , you Do have a vacuum leak

Posted by: Morrie Sep 16 2017, 10:57 AM

Congrats on the 912E. There are so few of them out there and even fewer with the L-Jet still installed, I encourage you to try and salvage it.

I have a number of friends who have fought battles with their Es and won. As an additional resource, if you have not done so already, go over to 912bbs.org and post on the 912E Tech Help BBS. The guys there are great and can help with some of the quirks that are 912E specific!

Best of luck! I loved my 912E!

Posted by: BK911 Sep 18 2017, 10:00 AM

Ok smart guys, hit a bump I've never seen before.
Checked dwell and it was a little low at 42^.
Checked timing and it was 50^ btdc at idle!
At 3500 rpm it was off the chart!
Car runs pretty well, except runs a little hotter than I expected.
How is this possible?
I didn't adjust yet, waiting for the electronic ignition to arrive first.

Posted by: Morrie Sep 18 2017, 11:02 AM

(not a very smart guy, but let me try and suggest something. It's a straw man suggestion, so others can feel free to knock it down)

Is it possible you got on the wrong plug wire, or are looking at an incorrect mark on the fan? You may want to consider doing a TDC on #1 sanity check...

Lots of ways to do it I am sure.... here is what I teach folks when they get mixed up adjusting valves.....

1) pull spark plug for #1 cylinder.
2) pull 1-2 valve cover.
3) pull distributor cap

You are looking for the following to all line up. (from memory)

1) rotor is pointing to the distributor cap tower going to spark plug for #1 cylinder.
2) #1 piston is at top dead center. I usually use a wooden dowel for this so you can visually see it go up and down. Just make sure it is plenty long so it doesn't drop inside the combustion chamber.
3) With both 1 and 2 above met, you should be able to spin the pushrods freely for both the intake and exhaust valves on cylinder #1.

Once you have all these criteria met, you can look for your timing mark. If I remember correctly, various fans had different marks on them, and it is hard to guess if yours is the original fan after all these years. Remember, the 912E has the engine serial number stamped on the fan shroud instead of the case. If yours has a number stamped on the case, likely its a 914 motor replaced at some point.

Kind regards,

Posted by: BK911 Sep 18 2017, 03:13 PM

Thanks Morrie!
Definitely on #1, checked several times.
Really surprised the car ran as well as it did.
Be curious to see what happens when I time properly.
Thinking Mr. Towle nailed it; lots of advance to mask vac leaks.
Might be needing a smoke tester!

Posted by: Dave_Darling Sep 18 2017, 04:36 PM

If you're using a timing light with an advance knob built in, check that it is set on '0'. Then you can use the stock timing marks.

Double check that what you think is TDC or the timing mark really is TDC or the timing mark.

I may or may not have committed both of those errors at various points in time. If so, I'm not admitting to it!

--DD

Posted by: rhodyguy Sep 18 2017, 06:48 PM

Does your fan have 2 timing marks?

Posted by: BK911 Sep 19 2017, 05:51 AM

Checked numbers on the dizzy and its a RPT VW06, which is apparently junk.
Have an 009 I may swap in and see what happens.
Or does anybody have a 2.0 dizzy for sale?
What other dizzies would be a good alternative?

Posted by: StratPlayer Sep 19 2017, 06:01 AM

123 dizzy, http://www.123ignition.nl/

Posted by: Perry Kiehl Sep 19 2017, 06:06 AM

A 1.8 distributor would be closest to stock.

I have a new Pertronix SVDA which would also be a much better choice than a 009. I also have a matching coil, if you are interested I'd make you a good deal.

Posted by: BK911 Sep 24 2017, 07:57 AM

The heat didn't work, and investigation revealed a broken flapper box cable.
Took out the hand brake lever and noticed quite a bit of rust in the tunnel.
Didn't think too much about it until I started tearing stuff apart to replace the cable.
That's when I noticed a puddle of brake fluid at the pedals and in the front of the tunnel.



So a simple cable replacement turned into this:

Posted by: GeorgeRud Sep 24 2017, 12:46 PM

Time to remove and rebuild the pedal box as well as replace the master cylinder. Try to keep the L-Jetronic and get the correct distributor- you'll be happier in the long run. Today's fuels don't play well with carbs unless the car is driven daily to prevent the fuel from jelling in the float bowls.