SaltySkoda

Well, that's right if you don't want the clearances too tight. But as I tried to explain, too loose is also a no-no. I always do it on a nice day in September. I'm pretty much driving about the same amount of kms every year so it doesn't matter. A new valve cover gasket isn't always needed, and I change it if I think it needs changing. It seems that the valve cover is rather warped from all the thermal cycles over the years, and it drools oil nevertheless I change the rubber gasket or not. However it keeps a natural anti-corrosive coating of oil on the front of the engine so I figure she does it on purpose 😁

Don't know about that, it may be a special Balkan edition 😆

It's not usual around here but I'm a weirdo in many other ways also. It's part of regular maintenance. Valves wear, valve seats wear, lifters wear, pushrods wear, camshaft wears... The valvetrain is one of engine parts that suffer the most abuse, it is critical to engine performance and tolerates no deviation from correct adjustment. You'd be surprised how much just a 0.05 mm difference means. It's not just about valve timing, it also very much controls valve bounce at higher rpms. The camshaft is precisely designed in such a way that upon the moment valve starts to open or finishes closing, the lifter is at constant speed (i.e. its acceleration is zero) thus minimizing valve bounce. Apart from valve bounce, it also minimizes the valvetrain wear. A nice presentation (in extreme conditions, however, just to clearly show the effect) can be seen on this video: This is a plot from a university textbook (in Croatian): X-axis is the cam angle. Y-axis is the acceleration. Red line is the valve deceleration caused by valve springs. Black line is the acceleration of cam-lifter contact point, and is approximately the ideal valve motion one wants at all engine speeds. Blue line is the actual valve acceleration. 4000 rpm is quoted as camshaft speed, corresponding to 8000 rpm crankshaft speed, because this effect escalates with engine speed. You can see the valve is not following the cam and bounces around. It's mainly the cause of "banging" exhaust sound you hear on redlining. So it's one of crucial things for engine performance and durability. The correct adjustment for 781.135 and 136 engines with all iron pushrods is 0.20 mm on all valves. 135B/136B, the more modern engines that have aluminum pushrods on inlet valves, and they should be set at 0.25mm on inlet and 0.20 mm on exhaust valves.

I accidentally posted an unfinished post, so here is the full answer: Well, she’s a GLX model, what did you expect? LX models that were sold here at the time had an analog clock instead of the rev counter, and no center console. That was pretty much the only difference. Power steering, A/C, ABS, airbags, motorized windows and all that stuff for wimps existed only in the user’s manual. They started to offer Felicias with fancy equipment at the very end of production, and as such they are very rare around here. No mechanic or bodywork specialist wants to look at my car because it screams "broke". Honestly, she looks like something that should only be driven to the junkyard, and is priced proportional to her weight. I don't really care. So I'm actually forced to learn how to do basic bodywork repairs, and I'm kind of happy about that. I didn’t mention it, but yes I checked the system voltage both in engine off and running / revving conditions to rule out the alternator. I changed the negative battery strap and cleaned all contact points a year ago. I also ran a separate wire from the battery negative lug to the electronic ignition module while debugging weird symptoms with the ignition. It always turned out to be the electronic ignition module, however. The original distributor was replaced because I thought it was causing issues, but again it was actually the electronics. OEM ignition module design is faulty as it allows water to get inside, so I recommend the more expensive plastic sealed type, manufactured by Viká. It pays out in the long run. I changed the battery many times over the years, and it always shows signs of slow turnover while starting for a few days or even weeks before it fails. But when it can’t turn over the engine it is usually enough to try a push start, even with the battery voltage as low as 9 volts which is enough to power the ignition coil. Did it all by myself on a few occasions on a flat parking lot, even in reverse gear one time going backwards on a steep hill. The alternator is perfectly capable of maintaining proper system voltage, provided the battery isn’t internally shorted (lead crystals grow on battery plates and eventually make physical contact). These small and simple 45 Ah batteries are still very cheap so I usually just buy a new one as soon as I confirm the old battery doesn’t keep its charge. It’s also good practice to check the battery cells’ acid levels every now and then, and top up with distilled water if needed. Ethanol is a problem for old rubber parts, i.e. hoses, diaphragms and gaskets, and can cause problems in cars that sat in a barn for the last 40 years or so. But today's rubber contained in rebuild kits and fuel hoses are somewhat more resistant to ethanol and don't readily disintegrate or solidify upon exposure to it. I change the spark plugs per Skoda's recommendation (every 30.000 km), because I'm worried about wearing out the threads on the head. We engineers have a saying: if it works, don't touch it. I don't think he's gaining anything by changing the spark plugs every year, if he's not doing a hell of a lot miles. Valve clearance is much more critical and I do that annually. Yes, well, I don't want to die in a car crash. I always take the MOT very seriously and never cut corners, especially when safety is concerned.

Well, she’s a GLX model, what did you expect? LX models that were sold here at the time had an analog clock instead of the rev counter, and no center console. That was pretty much the only difference. Power steering, A/C, ABS, airbags, motorized windows and all that stuff for wimps existed only in the user’s manual. They started to offer Felicias with fancy equipment at the very end of production, and as such they are very rare around here.

Actually no, as it was the coldest part of winter and what remained of the pigeon were just bones and feathers.

@D.FYLAKTOS Yeah, same here. That's why I always supply my preferred mechanic with new parts and detailed instructions on what to do. Some things you just can't do without a car lift and I don't have one, so sometimes I have to pay a workshop to do the job for me. My Felicia spends pretty much as per manufacturer's quote in the instruction manual, maybe a little more because of carburetor jets I've chosen. It also of course depends on how I'm driving, whether it's winter and so on, but it's always somewhere between 7 and 9 l/100 km. I kept an Excel table for several years for this calculation so I'm pretty much sure of the numbers.

Here's a photo from winter 2015. What you see are the remains of a poor pigeon. God only knows for how long I drove around with that in my car. Some animal rented my engine bay to make itself a nice restaurant. Probably a cat or a ferret.

Going off topic now, but I enjoy this discussion so much that I'm going to bend the forum rules a bit. Excuse me. It's not always about the years. Yes, 1997 might be fairly recent, but the car could have easily been made in the 1970s. The only thing digital on her is the clock. She doesn't even have a catalytic converter. Nowadays, almost no mechanic wants or knows to work on a conceptually old car. They just plug in the OBD, read out the errors and change parts according to a table the manufacturer gives them. No thinking required. A robot could do it. Mechanics that know usually reserve themselves for valuable oldtimers and don't want to spend any of their time on a car they don't appreciate. There is also the good quality parts sourcing problem. It's easy to find good replacement parts only for some old cars, and almost impossible for any other. This would be very much in relation what the mentioned 123ignition has in their offer, and what they don't. So, as shango066 often says, if you're going to own and use something of this age, you need to learn how to maintain and fix it. He's into vintage electronics by the way, but the same rule applies here for very much the same reasons. Over the years I collected various service manuals, diagrams and other documentation on my Felicia, and I'll be happy to share that with anyone that needs it. Just DM me. But the most important thing in solving puzzles like these is understanding of some basic principles, and taking your time to think and experiment. Parts quality is of course critical, as this story shows, so thank you very much @nta16 for recommending manufacturers you trust. They're going into my little notebook for future reference. Cheers! P.S. It's almost 313 thousand km, not 133. Or close to 200 thousand miles.

@nta16 You’re right, I don’t have much experience in servicing oldtimers. In fact, my ‘97 Felicia is the only car I’ve ever had. My family owned it since it was brand new. I learned much about cars and mechanics with her (and a ‘84 diesel Mk1 Golf we’ve had before her). Also she is the car I learned to drive on, so you probably understand our sentimental connection. Never had any real problems with her, apart from normal wear such as clutch, coolant pump, CV joints and whatnot. Still has the factory head gasket, the engine was never “opened” as we say here in the Balkans. She shows almost 313.000 km now and is still counting up. She has regular maintenance by my careful hands, and that’s all she needs. Don’t you just feel the love between us 😍? The Weber carburetor was installed just because I couldn’t source a rebuild kit for the original carb (actually a Pierburg 2E3 license made by Jikov) when it started acting up after 15 years of no maintenance. But it’s also much more fun to tune with all the jets to choose from. I never wanted to make her a “performance” car, and never used a rolling road to optimize the tuning. Just good old test drives. And still I overtook a Rimac Nevera on a highway around Zagreb (I guess they were testing it, they probably weren’t allowed to go even a little bit over the speed limit) a few years ago. That was some real fun! 😆 The new ignition distributor I bought was from Skoda-Parts.com, as they proved to be somewhat reliable and affordable (95% of the time, to be honest). Sticker on the box that it came in is shown on the attached photo. We do have a Skoda non-OEM spare parts dealer here in Zagreb but I learned the hard way to avoid them. They sell lowest quality parts for the local mechanic to get rid of a cheap car and its penniless owner. For some context, I'm a professional industrial automation engineer and this car is also a fun hobby for me, because I really enjoy solving this kind of puzzles. Now I'm learning how to MIG weld, for I need to fill some holes on her body(work) 😁. Thus, for me and my beloved beater, the junkyard as a default parts source is the optimal solution.

Thank you all for your input. I was right, the problem was in the new distributor. Although they have multiple ignition distributors that would physically fit the 781.135 engine, I quickly abandoned the 123ignition idea as soon as I saw their prices. Searching through my stash I actually found the distributor the car came with, from the factory (mine says MAGNETON 443 213 204, see photo). Cleaned it up, filled it with oil, lubed it where it should be lubed and installed it. I only replaced the original pickup coil with a new one. Works perfectly. I guess the moral of this story is to NEVER trust new parts. Along the steel brackets issue, an autopsy of the replacement distributor found that the field magnet wasn't drilled exactly through its center, and as such rubbed on reluctor rotor. I also found large pieces of the magnet inside the distributor. So, I would recommend everyone to rather visit a junkyard and search for OEM parts, especially for a car this old.

I think I found a probable cause. The brackets that hold the pickup coil are made of a ferromagnetic material (most probably steel), where they should be brass or aluminum (i.e. something paramagnetic). What I'm talking about is shown on the attached photo. Left is a bracket from the original distributor, and on the right is from the new one. These steel brackets are disturbing the rotating reluctor magnetic field and wreaking havoc with my ignition timing. Now I'm trying to find the rest of original brackets in my parts stash hoping that would solve this issue, but I'm not going to assume everything else will be fine with this ****ty distributor in the future. So I'm still open for suggestions about a good and reliable replacement distributor. 123ignition maybe?

It's been a very long time since I've last posted, but I'm proud to say that my Felicia is still kicking ass. And I want to keep her that way. She has a classic 1.3 engine with a good old carburetor (changed it to a Weber replacement with manual choke more than 10 years ago) and standard distributor with a magnetic pickup. The engine stalls when I blip the throttle, and even shuts down if I really floor it. Obviously, I thought, this is an accelerator pump or fuel flow problem so I thoroughly cleaned and rebuilt the carb. No change. Then I checked the timing with my strobe light and found the spark just cuts off when the throttle is depressed hard and fast enough. It doesn't always do it, but in about 9 out of 10 times I try. No problems on maintaining high revs. So this is actually a distributor related issue. Spark timing on idle is just fine. The engine also dies immediately if I disconnect the vacuum advance tube to the carb. For test, I adjusted the dizzy angle so that I can keep the engine running when disconnecting the vacuum line. The stalling problem wasn't there anymore and she happily responded even to savage flooring without any misfire whatsoever. But I want to use the vacuum advance for better economy since she's a daily driver, and fuel prices are ridiculous. I also replaced the electronic ignition module along with the ignition coil, spark plugs, cables, dizzy cap and rotor. I haven't touched the vacuum advance return spring adjustment nut and washer, and the points movement resistance and return seem fine. Since this is the third dizzy I tried (similar ignition problems always developed over time), does anybody here know where one could buy a good and reliable replacement distributor? It doesn't have to be standard magnetic pickup type. Thanks!

In real life, it is impossible to keep the crankcase 100% clean of small hard particles that may come from outside or as a result of normal engine wear. It may be a very small amount here and there, but in this particular case the damage had a chance to accumulate over 23 years and nearly 300,000 km of almost daily driving in all possible conditions. The pump needs all its clearances to be within range, in order to provide pressure. Otherwise, surface tension can't keep the oil from running around the gears, effectively reducing pressure and output flow. After a lot of searching, I managed to find a Belarus-based merchant that still has a new set of gears for this pump. I'll take the backplate to a machinist. That seems to be a good advice, I'll check that for sure. The pressure valve spring was strong and I didn't notice any problems with the mechanism.

Yeah, well, the timing chain was replaced by an authorized Skoda service shop some 10 years ago. Nobody else had any need to touch the oil pump. The pump should be factory original as far as I know. Keep in mind that the pump runs on unfiltered oil: any debris could have caused the scuffing. Only the strainer assembly is available as a new spare, not the pump gears. I can only buy a pump backplate (as a part of the strainer assembly). I called several parts distributors today. So, should I just resurface the pump backplate (or buy a new one) and hope for the best? There doesn't seem to be much alternatives.