gas in the crankcase, weber 40-idfs versus L-jet

[ewic]

Carbs were running really rough. Turns out two idle jets were clogged. I replaced these, now it won't start. I checked the oil - it was really high, and I get gas fumes. I am thinking I have a flooding situation, and the gas has been going thru the intake manifolds and filling the crankcase.
A few questions for the gurus: I assume changing the oil is required so I don't blow my house up.

Is it impossible to run L-jet on a 2-liter displacement motor? I tried once, no workee, but when I took it all off I realized I had the two gas lines switched, so my fuel pressure regulation at the fuel rail was afu (all f***ed up). Word on the street is that it (L-jet) is too lean to run 2-L? Anybody ever try to fool the temp sensor on the head with a resistor to make the fifth injector run all the time?

I am seriously considering installing the L-Jet again, tonight. but I hate to start a fools errand, and spend two hours hunched over in the engine bay, cussing in German.

I suspect the L-jet is less likely to flood the crankcase. And I suspect the webers need a full rebuild.

I am running 1.8 heads with 2-L crank, rods, P&Cs. L-jet was running great before the rebuild.
Thanks for the advice. Eric in Virginia

[aircooledtechguy]

Sounds like you are having fuel get past the needle and seat in the carb which is causing the float level to be too high. This caused fuel to dribble out of the main jets upon shut-down. This fuel gets past the rings and into the oil.

If you had the lines X-ed, it will NOT run at all. The pressure regulator works as a check-valve if you try and flow fuel backwards through it. Nothing more rock-solid than a good running EFI system. I would try the L-jet. There's a lot of "internet parroting" concerning whether or not you can run a 2.0L on a 1.8L L-jet system; few have actually tried it but everyone seems to be an expert on it. . . I won't speculate because I have never tried it. Hooking up an O2 sensor will you know definitively and will allow for tuning. . . However, if you do, let the rest of us know how it works. I have a 1.8L that is tired and would love to bump it up to a 2.0L but keep the L-jet. . .

[ewic]

Yes, with the L-jet, that is what happened. Before the 2L conversion Bosch L-jet ran fine. After the rebuild it didn't fire up at all, because I completely botched the fuel lines. I should have done some simple diagnostics and saved much headache. I am putting the L-Jet back in now and I'll keep you informed. I figured I had to yank out the carbs anyways to rebuild them. Unfortunately I don't have an O2 meter. At least I can say whether it runs, runs well, or doesn't run. I might be glad I kept the mild cam in there (Webcam #73), so at least the cam situation is good.
I got a good feeling last night putting in an ecu, and hooking up a bunch of sensors. Webers sound cool, but those idle jets sure get clogged alot. Thanks Nate!

[Piledriver]

Some grease on the air filter seals/bases does wonders, The K&N filters (esp. fake K&Ns...) leak rocks.
K&N actually flogs thick, sticky, waterproof grease (like the stuff for urethane bushings) explicitly for that purpose.
(No one CARRIES IT for some unknown reason ... Perhaps they think "air filter grease" is a gag item. It isn't.)
http://www.knfilters.com/search/product ... =99-0703-1.

Available in a 6 oz party size tube as well.

Various places also sell "Jet Doctors", which are essentially snorkels for the idle circuit, the way IDFs are designed any crud that gets by the air filter and on top sooner or later gets flushed into the idle circuits as if by a funnel.
RAIN make it much worse, if the engine is exposed make rain hats.

Webers/Dellortos cannot tolerate much more than 3 PSI fuel pressure or they pee.
2PSI would be better.
If you haven't measured it, you have no idea, don't believe what the guy that sold the pump or what the numbers on the regulator say.

If you are still using the EFI pump on the Webers... buy plenty of marshmallows for the car-be-cue.

I see no reason 1.8L LJet would not work on a mild 2L, but be prepared to make, repair (properly) or buy a new wiring harness, 95% of the time that's at least AN issue, if not the issue. It has limited tunability, but should work fine with some massaging, you may want to add a MAP-based enrichment circuit, using a programmable SMC vacuum/pressure switch. (depends on the ECU if you have a full throttle switch, use that input)
You can buy a better-than-new harness from several sources if it comes to that.

A WBO2 is not just a Good Idea, think of it as insurance for your motor.
Without one you are not tuning anything, you are randomly playing with it and hoping for the best.

[ewic]

It runs, but rough right now. I think I have loads of "false" air. I will try to find the "air filter grease" for the big boots that connect the plenum to the intake pipes.
I am having trouble routing the little (4mm, 5mm) vacuum lines. I have found Pete Klager's diagram, but my car doesn't have an egr valve, so the diagram isn't quite right for this 1976 1.8 914. Right now its plenum + decel valve + fuel pressure regulator linked together with a tee. There is one nipple on the throttle body that I connected to the vacuum advance on the distributor. I think this is wrong. Should this connect to the vacuum retard on the distributor? The Haynes manual is pretty much useless on the subject.
That is good advice on the WBO2 and a new FI wiring harness. My harness is crunchy with age.

[Piledriver]

If the boots are in decent shape, no help is needed.
It's primarily to make the gauze air filter seals work, as they are too hard, and you cannot really crank on the filters.

If you are starting a new project (installing /retuning LJet) you may want to start a fresh thread and just link to this one.

[ewic]

The boots are old, and for some reason they don't line up 100% with the intake pipes. The mis-allignment is making the leaks. I think I will add 8 pipe clamps to do battle with the leaks.

I found more useful vacuum line diagrams here: http://www.ratwell.com/technical/VacuumHoses.html

I will start a new thread and link it if problems continue.

[Piledriver]

Let us know how it goes, we have a great fuel injection forum here.

[ewic]

L-jet worked ok. Just the stock system - no modifications or tweeking. It runs, but it feels like about 40 hp was missing relative to the Webers. I sold the machine - we are headed out west, and it was a good time to loose a couple of cars. New owner is a mechanic and motorcycle enthusiast - he is going to build a "trike" / three wheeled motorcycle out of it. I told him about the jet doctor kit and gauging the 2-3 psi instead of beleiving the dial.
If I had the rebuild to do over again, I could see spending more time rebuilding and setting up the carbs, and going with a little wilder cam. If I do try to revive another 914, I might look around in the deserts of the SW. The east coast VA/TN has just rusted the bejesus out of the old porsches, especially the floorboards and hell hole spookfest - not much left to bolt the project to!! Tanks for the help!!! Eric

[Piledriver]

Win some, lose some, stop back by when you get settled and say "Hi"!

SW has a few low rust 914 floating around, mine had been parked for ~20 years with a "broken transmission" (shift coupling fell apart, gotta love transmission shops)

Mice did a lot more damage than the battery.

[Jadewombat]

L-jet is fairly adaptable, what cam were you running? One thing is the flap doesn't like a lot of cam lift or overlap. About the only two things you can adjust are the tension on the spring flap (if you use a slightly hotter cam or higher lift rockers) or adding a bit of resistance to the temp. II sensor. There's the trim on the airbox too, but it doesn't do very much. Otherwise the system should adapt pretty well between a 1.8 or 2.0, the injectors for 1.6-2.0 were identical just the control units (ECU) differed.

The stock L-jet system has a WOT switch built into it (at least the 2L. systems did) so probably don't need to have the 5th injector run all the time.

[ewic]

It has a webcam 73 in it. I had played with the spring on the airbox a little, but as Pile suggested, without an O2 meter, your really just guessing. One of the big vacuum hoses going to the decel valve completely collapsed. I fixed that with a hose having beefier walls than stock. I could see adding resistance to temp sensor #2, but I would be shocked if the missing HP showed up. The engine is trying to breathe. I could see going with a CIS system or the CB performance setup. The CB rig looks simple and looks like a lack of air-constriction. I sold the whole deal to a machinist a couple of weeks ago. He is going to build a trike/three wheeled monster. I recommended rebuilding the weber idf 40's, and playing with the jetting. Maybe a loop circuit for the fuel would do better than the one-way flow that I had going from the tank. Thanks for the input. E

[Piledriver]

EFI on the stock manifolds should be at least equal to or outpull the Webers at ~anything but pkhp on a stockish motor, and maybe then, IF tuned right. This includes LJet, although the AFM is a small restriction.

I'd do a CIS conversion again, but I think I'm done with distributors now, I'll only run a programmable ignition
(and may, although my MS setups seem to be breeding, and one went to college and is a MS3 now)

Without a WBO2 and EGT at least, it's all reading tea leaves. (there is still some of that with a WBO2 and EGT)

The VW intake system was very well thought out/designed, at least for the factory powerband.
Shorter runners/widen plenum, and a filter on the TB directly completely changes the powerband.

It will not sound anywhere near as powerful, lacks the sweet music of a set of Webers/ITBs.
But it will probably have a much fatter power curve.

Bummer you had to swap it off, but there will be another.

[ewic]

Hmmm, the L-jet must have had a problem that I never figured out. Wiring harness is a distinct possibility - ancient for sure. Wish I would have diagnosed it more to reap the rewards.
On the bright side, the 75' was becoming a rolling, rusty death trap. Kind of surprised the right front engine mount never broke off on the freeway (extreme hell hole damage). I could definitely see working on another one, starting with a more solid body.