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Sat Apr 05, 2025 1:37 pm

Thanks, Jim. I installed it with Sika 710 (I think, I'll check tomorrow).
Today, big breakthrough, engine started and I made the first run in, 2000 rpm for 20 min, as per Engle instructions. But a job I thought it would take 2h took me the whole day. Good thing I had a good friend help me. Tomorrow full story. But it runs!!!

Sat Apr 05, 2025 5:20 pm

tzepesh wrote: Thanks, Jim. I installed it with Sika 710 (I think, I'll check tomorrow).
Today, big breakthrough, engine started and I made the first run in, 2000 rpm for 20 min, as per Engle instructions. But a job I thought it would take 2h took me the whole day. Good thing I had a good friend help me. Tomorrow full story. But it runs!!!

It always takes twice as long and 3 times what it should cost!

Glad you got the engine broke in! Nice job!

Mon Apr 07, 2025 2:50 am

Well, just the activities related to some new parts take longer. If you think about it, I got it almost complete in ~1 month, working evenings and some weekends. And not every day.
So, the story about engine: I ordered some new engine tins, as I did not have all original ones. It was very hard to align the holes and install bolts. I had to grind larger some holes.
Intake: preheat holes on the new exhaust did not line up perfectly to the ones on the original manifold. I had to file the holes a bit larger.
Carburetor: the studs were too short. The intake came from a California car, with EGR, and it had a thicker flange. So I took an older rocker stud, threaded some more, and made the calculation about length: 13.5mm intake flange, plus 1cm for nut and washer, plus 5mm buffer equals... well 15mm in my quick math :D. So it did not fit, it was too short, go back, find another stud, thread etc.
OK, all installed, let's start it. Put gasoline in carb, pull the lever a few times, get fuel all over. Take carb off, check acceleration pump membrane, seems a corner folded during install. Swear, install correctly, re-install carb. Crank engine, nothing. We could see spark was missing (I have an electronic controller with LED to check. Clean points, nothing. Voltage is there. Replace distributor with the AL I had. Clean points, we have spark! Still does not start. Check fuel, it squirts some, but no fuel from pump. Install electric pump, crank, vrooooom! Keep it at ~2000rpm for 20 min, runs very well, no vibration, keeps revs up, smells ok.
Next day: try to squeeze in a 1.6 in a 1.2 car. HArd, but I know many of you did it before, bend some tins, it's in!
So now to finish wiring the engine, check electrics, install seats and drive.

Mon Apr 07, 2025 3:40 am

And a question, related to horn circuit. I understand how it works, as in the picture below. But when I measure continuity, I have ground on steering tube, and no ground on the steering box. Stwering box I can ground with a wire, no issue. But where is the steering column grounding? I have all rubers: the one on the splash panel, the small one between tube and trunk sheet metal, the large one between ignition switch and tube... And this is with steering column unlocked, I thought maybe it grounds through the lock rod.

Mon Apr 07, 2025 2:26 pm

Biiig day today! First hundreds of meters on its own power. We have steering, brakes, all electrics good, engine runs nice. It revs very much at start, but I guess it is the choke not closing completely, I have to adjust. Movie when I have some time to upload to youtube. It was 10.30 PM, and I was so excited I even forgot to switch on the lights.

Mon Apr 07, 2025 3:02 pm

tzepesh wrote: Biiig day today! First hundreds of meters on its own power. We have steering, brakes, all electrics good, engine runs nice. It revs very much at start, but I guess it is the choke not closing completely, I have to adjust. Movie when I have some time to upload to youtube. It was 10.30 PM, and I was so excited I even forgot to switch on the lights.

Awesome update!

Thu Apr 10, 2025 12:22 pm

Gentlemen, I need advice. I posted also in the engine section.
I have issues with idle. So, think about a stock engine with Engle W90, Solex 34 pict3, stock SVDA.
How it behaves: turns on perfectly, runs well with choke on, but when it gets hot, does not want to idle. It responds to screw tuning, at some point it seems like it idles well, then dies. Sometimes RPM oscillates depending on tuning, I checked for air leaks with carburetor start spray and it does not accelerate, therefore no leak. Carburetor shaft is bushed.
Also, if I rev it and suddenly close the accelerator, it dies.
I tried with transparent tube from pump to carb, it is always full. I have the correct rod for the alternator pump.
I tried with another carb, same symptoms (but I did not try to adjust the screws, it was coming from a running 1.6).
Idle jet not plugged.
Plan for tomorrow: test charging voltage, check fuel level in bowl, check how it runs with electric pump, check output of fuel pump by using a transparent filter, use lambda sensor to measure exhaust. I need to get it running tomorrow, as I have to get it to the equivalent of MOT or DMV.
Any advice would be appreciated, what else to check.

And a few pictures.

Fri Apr 11, 2025 1:38 pm

Problem solved! I had two shims under needle valve, adding up to 1.6mm instead of 0.5mm. Then reset screws, started, heated, screwed out the small adjuster until it did not die. But it was shutting off aftwr closing the throttle very fast after reving. So, hooked up the lambda sensor, it was too lean. Adjust small screw until I got ~13.8:1 AFR. It still died at quick throttle closing, and I could see a very lean condition. So, screw in the air bypass screw until I got a reaction (I think I got around 1 turn out from fully seated), reset the mixture screw to get back the afr, not it runs as it should: starts right up, revs well, no stumble, idles well, does not die.

It was leaking a lot of oil out of a pushrod tube, I stuck a lot of RTV around as a quick fix. But I will have to address it properly.

Mon Apr 14, 2025 12:50 am

Hi Tzepesh,

Could you please give more detail on your carb tuning setup? Apart from the lambda sensor, what more do you need?

Mon Apr 14, 2025 4:50 am

She's looking beautiful!

Mon Apr 14, 2025 8:32 am

Nice job finding that second shim. When you reset the basic idle speed and mixture, did also rest the timing? That should always be rechecked, as it can change a bit during that tuning ritual.

Hope your inspection goes well!

Mon Apr 14, 2025 10:56 pm

I'll answer one by one.
@Scarabee: timing light is a must. Lambda sensor and controller not really necessary, but I have them and it helped to work with numbers, not by the era as the manual describes (I'm an engineer, I like music, but my ears are not good tuning devices. My wife, however, is also a musician, maybe it would work for her).
So, procedure is as in the pictures below (from my Haynes manual), with some changes. Start with basic tuning: idle speed screw setting, then bypass and mixture out 2.5 turns. For me, when it warms up, with this seeting it does not idle, so first thing I had to do was to screw out the mixture screw (small one) until it did not die. Then did the timing (7.5 deg BTDC), then proceeded with the normal tuning procedure. What I missed was tuning the bypass screw, and I found I had to close it quite a lot until it reacted. Lambda sensor helped me see that I had a lean condition on fast throttle closing, so too much air bypass. Normally, when you tune with lambda, you get close to ideal exhaust concentrations, like in the picture below. I also checked mixture at higher revs, because that is what is being measured in my country at technical inspection. Well, t looks like even with lambda tuning, I still got it a tad too rich (beetle likes it a bit rich, not at 14.7), and some measurements were over the limit.

@Stetoppingphoto, thank you! Not perfect, not a concours restoration, but a nice car to be driven.

@VW_Jimbo: Yes, I also checked timing. Stayed spot on at 7.5 deg, but also the idle speed was set around same value, 900RPM. And it passed technical inspection. So now to finish paperwork and get new registration. And finish installing all accessories (fender stone guards, flower vase, still waiting for seats upholstery).

Mon Apr 21, 2025 1:29 pm

Not much to show, waiting for paperwork for new license plates.
But I have a question: I have the old stype sunroof guides, all made of plastic, not with steel tubes from the gear/middle section to the rails. It seems to be quite a bad design, as the cables flex inside and tend to come out of the plastic guides. I would like to switch to the newer design, but I can not find the metal guides (well, just on is in stock at hoffmann-speedster), and I tink I can easily bend some tubes. But I need a measurement of the inside diameter and outside diameter. Can anyone please measure?

Tue Apr 22, 2025 1:32 pm

Hopefully I will receive a set of sunroof tubes from a friend, in about 2 weeks.
Another issue I tried to solve today was wiper mechanism. It hits both the lights switch and the wiper switch. I have a 70 and later assembly, but it fits very well and I compared the linkage rods and all looked the same as the older assembly I had. So what would be the solution? I will take off everything in the next days.

Thu Apr 24, 2025 12:55 am

Solved the wiper mechanism. Motor was in the wrong position (well, the usual 3 bolt pattern is mirrored for the linkage I have, but I flattened and drilled new holes). Also one of the linkage arms was upside down, and I screwed out the pivots about 2mm. Now everything fits well, no interference between components.
Finished wiring the horn, it looks like the steering column tube is not grounding, after all. But I had to add a ground to the steering box.
Wired the reverse lamp with a microswitch controlling a relay, activated by a tab on shifter linkage (as per old Hella design).
Wired the AUX to the radio, so now I can have radio or BT depending if a jack plug is present.

Sorry, no pics, it's been raining and did not take the car out.
Still to do:
1. re-tune the carburetor, I changed the idle jet to 55. But for this I first need new cylinder head gaskets, because I changed the oil and checked the valves and the old gaskets got ripped.
2. Raise the suspension one notch - next week
3. address the new Robri reproduction fender guards by Flat4. They do not fit at all, and I have no idea how to bend them (I guess heat). I have not worked with cast aluminum before, and I saw everybody has the same fitment issues...
4. still waiting for seat covers by TMI

Thu Apr 24, 2025 8:46 am

Head gaskets? I am certain you meant valve cover gaskets. Unless you meant the old copper head gaskets they used back in the day!

Bending CAST Aluminum. Hmmmmm. That is scary! That is not a good thing to have to do. Seems everytime I have tried bending it, it breaks. Not sure heating it is the right path, since bending it will produce more heat, possible making it hit its fail point sooner. I wonder if you could do the bending in water, slowly. Like a tub of water, to pull the heat out from the piece during a really slow bend? Might have a better shot at a good result. My 2 cents.

Regardless, I wish you luck!

Thu Apr 24, 2025 11:09 am

Yes, valve cover gaskets.
Thanls for the tip. I am also quite reluctant to work on those gravrl guards. Also, others had to cut and weld the fenders, too. This would be also my case, as they are not wide enough. Tested by others on original and repro fenders, fitment was the same... I simply can not understand how Flat4, who are well known for high quality products, can manufacture these so badly. I think they will stay o the shelf for some time.

Wed Apr 30, 2025 1:41 pm

The carburetor setting gives me headaches. I tried the method described here
http://www.vw-resource.com/34pict3.html
I can not get it to idle using the air bypass screw. It runs on choke, but once the throttle plate closes, it will die. I suspected the "fast idle" screw being improperly set, so I tried to feel when the carb barely creates vacuum for the dizzy. Well, it the fast idle screw was set properly.
Check several times for air leaks, with starting fluid, and watching afr. Only when I spray it at the filter intske I can see a sudden change, no leaks.
Still, it does not react to air bypass adjustment. Only when I screw out the mixtrure screw for about 6 turns will it idle, and will run the same even with the air bypass fully seated... What on earth?

Thu May 01, 2025 4:11 pm

Great project. Your W90 has a bit more duration than stock. You may want to up your idle RPMs a bit. Mine has behaved similarly but produces great torque on a small motor. Cheers

Wed May 07, 2025 11:24 pm

Another big step, we got it registered, so all legal now :). And we took it for a ride, runs pretty well. I would shorten a bit the brake pump rod. I adjusted it longer, to have at least 20 cm from splash panel, but the pedal position is not "natural". And it affects the clutch pedal in the same way. And to work some more on the carb. It starts, it runs, it does not die, but idle is too high and irregular.