From 2015 all posts are in English too. Feel free to comment, all posts are open for that – Appreciate any feedback or questions. This blog is about a fine -64 P1800 with four owners including me since a couple of years and I hope someone find it worthwhile reading. Thanks for visiting!
Tack för att du hittat hit. Det går utmärkt att kommentera, ställa frågor eller ge kloka råd. Under varje inlägg finns en länk ”leave a comment”, all feedback är bra feedback och gör i bästa fall denna hobbyblogg läsvärd. Det har blivit mycket mer trafik än jag trodde så du är nu en av ca 300 besökare denna månad, så verkligen – Välkommen!
Had my car fitted with expensive whitewalls rather than the fake sides that I’ve had for a couple of years that quickly turned ugly. On my car the fake walls grinded themselves against the tire producing unwanted noise – and started to turn brown/orange on the edges after just a few month. What I got now is BRGoodrich 165×15 (80).
It was also time for toe-in adjustment and overall checking of the steering. My steering wheel was slightly off-center and that can be fixed at the same time – if not too far off. Happy with the result. An added bonus is that I finally have a a functional spare after many years crossing my fingers not to have a flat tire. At the shop:
So after 9 days it was time for the workshop to take a look. When I came to the car that morning it started fine – and engine running normal. What? So 2 weeks earlier I had a dead battery and last week the engine felt like running on 3 cylinders. And now it just decided to repair itself. Anyhow I drove to the workshop. Bertil was very busy and had hardly time to listen to my story that morning. I told my story and asked him to check any plausible clause for the strange problems I’ve had – and asked him to change the battery cables on both poles. Just in case.
I collected the car the day after. Battery cables were just fine. What Bertil found was that the main ground cable (earth-lead, ”stomkabel”) between engine and body was loose. He made a new and re-fitted it. I’ve heard about that cable before but never checked it. It is crucial for the engine as it can provide ground for things like generator, starter-engine and essentially (in my last case) for the sparks generated at the plugs. With a faulty cable any of the three can potentially go wrong – fully or partly. Here’s an image from the workshop manual. It should be found far down below the battery above the exhaust – connecting the bell-housing (”sprängkåpa”) to the chassi.
Now, that cable have probably been loose:ish for some time. So what has it to do with an empty battery and an engine that lost 40-50% of its power? Here’s my explanation:
Empty battery: though I’ve been measuring 14V+ over the battery with engine running, the generator failed to deliver enough current for the charging. The volt-meter doesnt require any current (really) so the lack of Amperes passes unnoticed. Another possibility is that sometimes – but not always – it has not been 14V+ when engine running – and I have failed to notice the charging lamp. Either way, the car has been running on battery charge eventually emptying it during this spring.
Powerless engine: without proper grounding for the engine the sparks wont ignite the fuel/air mixture as it should. Also accounting to a certain smell of fuel which I hadent noticed before. The loose cable was affecting the grounding un-regularly so (just a guess) every 3rd or 4th spark went bad whereas the other were ok.
A nice side effect is that my usually quite un-stable idle (around 800-850 rpm) has now become rock steady. Most likely caused by the varying ground condition caused by the cable.
Sry if this explanation sounds like bleeding-obvious to many, I write it as much for myself as I learn new stuff from every mishap.. Here’s a shot of the culprit and the solution, much in the same position as above. The metallic tube below is my single exhaust pipe. The spiraled tube is the oil temp sender and the transparant tube in the foreground is drainage to an air inlet. Bottom of Engine to the right in faint red – and cable bolted to the bell-housing.
So I’ve been to Prins Bertil Memorial a couple of years now and EVERY time my car has gotten a new problem. This was the third time and there’s a saying in Sweden ”If you fail twice, third attempt will work” (in Swedish, ”Tredje gången gillt”). But it wasn’t to happen. All packed, coffee in thermos, sandwiches and everything ready to go. But when we got to the car nothing happened when trying to start the engine. Apparently dead battery or faulty starter engine. Just a couple of days ago the car ran like a clock – and all of the spring and has done so since last summer. But now it was the day of Prins Bertil Memorial and the ghost arrived exact day again.
We roll started easily and off we went. At the scene along with a couple of hundred other cars we met with a few other P1800’s. Among them this beautiful E. My car is visible behind with open bonnet trying to figure out what was wrong. Behind my car is a third red P1800 and this guy had a Voltmeter with him. Perfect.
Battery read 12.1V whereas a fully loaded one should usually read 12.6-12.7V. Now, this was strange as the battery was new (last summer) and generator got new coals after last Prince Bertil (a year ago) and with engine on the loading charge measured 14V+. Which should mean battery is loading. But still the reading said battery was close to empty – not able to power the starter engine. A lot of helpful people came around and the possible clause was – we concluded – a bad battery.
So after the weekend I had the battery checked. They charged it over night and performed some tests. They said it was ok. And when re-installed in the car everything worked just fine again. And with engine on I again read some 14V+ over the battery so apparently no problem with generator (or voltage regulator). Sigh.
Motorhistoriska Dagen, Stockholm, Edsberg Castle
End-of-story? Sadly no. Next weekend it was another big gathering coming up, Motorhistoriska Dagen – ”Motor History Day”. This particular morning it started fine, but when pressing the pedal it lacked power. Felt like running on 2-3, rather than 4 cylinders. Some fuel fumes now and then too. At first the new problem appeared all different form the previous but eventually – 1.5 week later – the source was found.
Anyway, we went to the place and here we are at Edsberg Castle north of Stockholm, running – but badly. 2nd image shows Max, one of the helpful guys (driving a PV 544, previous depicted in this blog) and last a nice Ford (who’s owner, BTW, is the out-of-focus woman in the shot of Max). Love the look of that Ford.
Again a lot of helpful people gathered and all kinds of things came up as what could be wrong. Main contenders were something with the ignition – or – with the carbs. So for ignition I checked the cables, the plugs, the breaker points and all seemed fine. Perhaps something with the carbs? Lifted the lids to the floater chambers and no dirt there – and valves ok. Fuel flowed too so no apparent problems with the pump. Later, with the help of a video I found: ”Dylan’s 544 #3: Setting those SU Carbs!” I checked all what he talks about. I can’t recommend videos like that enough, there’s a link under ”links” (or just google the title). Love guys like this Dylan sharing his experience like that – lowering the threshold for guys like me to do the same thing. So I lifted the vacuum clocks, checked the needles and inlet valves and so forth but nothing looked bad there either.
In summary nothing appeared to be bad with the ignition with all voltages looking ok and nothing bad with the carbs. Hence still a mystery. So I threw in the towel and got a workshop appointment with Bertils garage. His workshop is cramped this time a year so I had to wait for 9 days, but was pretty confident he would found something.
Har under åren fixat en massa med mina förgasare men kom på att jag inte lyft plastlocken på klockorna på länge och mindes att ”där ska det ju finnas olja”. Jag öppnade locken, drog upp cylindarna och tittade ner. Såg ingen oljeyta men cylindrarna var inte torra – och det ”smackade” när jag lyfte upp dom vilket åtminstone betyder att det inte är torrt.
Debatten ang. vilken olja verkar lagom förvirrad. Men den här borde räcka för de flesta. Kommer från en av Volvos verkstadshandböcker som behandlar SU-HS6. ATF alltså, ”Automatic Transmission Fluid”. Det går säkert bra med en del av de andra tipsen man fått, symaskinsolja – eller för att vara petig: ”Singer Symaskinsolja” var tydligen något racingfolk experimenterade med för att få ännu mer respons vid gaspådrag och full gas. Strunt samma, idag är det ATF som gäller, vill man ha prestanda kan man gå och köpa en Subaro Impreza eller nåt annat utan kön. Även SU-experten Förgasarteknik i Söderköping rekommenderar ATF och den är betydligt lättare att få tag på – och samma sak som i de dyra små flaskorna.
Så igår fyllde jag på lite olja i förgasarna. Det krävs minimal mängd för att fylla upp dom. Man ska fylla upp så man ser ytan, inte ända till toppen för det kommer bara rinna ut ur de små hålen som finns i plastlocken eller förbrännas inne i motorn. När jag sen tryckte ner de två ventilerna igen var det ett HELT annat motstånd, det var plötsligt ganska trögt att få ner dom, stor skillnad mot när jag bara kollade dagen innan. Provade motorn och märkte att gasen svarar MYCKET snabbare.
Det fick mig att fundera på funktionen. Det finns mängder av litteratur på SU-förgasare men de allra flesta tar upp ALLA funktioner, inställningar och detaljer och det var inte helt lätt för en amatör att sortera ut vad som händer med just denna olja och de där små cylindrarna man lyfter upp med plastlocken.
Så här är det. Se bilden nedanför. Kanske basic för en del men inte för mig:
1) Vid gaspådrag (orange spjäll öppnas) så vill den gula cylinder uppåt men dämpas momentant av oljan: dvs mindre luft/mer bränsle, alltså temporärt fetare blandning. Ungefär som om man kunde choka motorn en kort stund. 2) En kort stund senare ”hinner den gula cylindern uppåt” så att blandningen blir balanserad. Hur kort beror på fjädern och annat men upp kommer den. Och då rullar motorn på balancerad blandning på det högre varvet. 3) När sen gasen släpps så faller gula cylindern ner utan dämpning, dvs motorn får mindre fet blandning direkt. Här har oljan inte betydelse då dämpcylinder fungerar som en öppen backventil när den gula cylinder ska ner. Med eller utan olja spelar ingen roll, den går ner lika snabbt ändå. Motorn hamnar direkt på lämplig bränsleblandning för ett lägre varvtal.
Summerat så ska alltså – med rätt mängd dämpning – gaspådrag ge snabbare varvtalsökning (pga momentant fetare blandning). Men sen, när man släpper gasen så tappar den varv snabbt (gula cylindern faller ner). Detta sker oavsett olja eller inte. Så det är just gaspådraget som ska påverkas positivt. En annan (möjligen negativ) effekt är att bensinförbrukningen bör öka.
Sen ska oljan tydligen göra tomgången mer stabil eftersom plötsliga variationer i luft/bränsle-blandning dämpas.
Carburetor, Carburettor, Carbs or as SU denotes them, Carberetters, in original prints. I’ll settle with the first as it gets way more hits than the others in Google Search.
While I have done a lot with the carbs during the years I had somehow forgotten about the oil in the dampening cylinders. Mine wasnt dry but needed fill, but what oil? Confusing opinions on the net but ATF is the thing, ”Automatic transmission fluid”, and have the right viscosity. The ATF image on top are form a Volvo manual from the late 60’s. ATF is way easier to find than the expensive original fluid. Anyway, throttle response after filling them got way better. So I started to think about the function.
To me, TOO MUCH information are available covering TOO MANY aspects of the SU carbs, so I settle here with what the oil’s purpose is. Colors refers to the last image. Note that the yellow cylinder (”dashpot”) in the ”flask” moves up and down depending on the throttle – manipulating the richness of the mixture of air/gas flowing into the engine. This is probably basic to some but here goes logic:
1) When the gas pedal is pressed the orange throttle opens the inlet to the engine cylinders and air suction starts. The vacuum created sucks the yellow dashpot upwards. But it is dampened by the oil meaning the engine momentarily gets a richer mixture (more gas/less air). It’s almost like (if it was possible) using the choke for parts of a second, doping it momentarily. 2) A moment later the yellow dashpot has – with delay – moved upwards and the mixture air/fuel get balanced. Engine now happy running on a higher rev. 3) When the foot leaves the gas pedal the orange throttle closes, suction from engine reduces and the yellow dashpot moves down quickly. It will drop quickly regardless if there is enough oil or not, revs go down quickly. The oil only dampens the yellow dashpot when it wants to move up, not down.
So in summary oil discipline here makes throttle response quicker. From now on I’ll check two-three times a season. To my car it was a big difference. This despite that my carbs were well tuned otherwise as probably evident to those that have read other posts in this blog. An expected negative effect is that fuel consumption should increase a bit. My engine has been very lean consuming less than a liter per 10 km anyway so no big thing. And I got a quicker car, more easily revving up to a nice throaty engine sound.
And another thing with the oil, as it dampens movement of the yellow cylinder also at low revs it will also make idling more stable.
Har haft den i fyra år nu och kan inte tröttna på linjerna. Här en fin bild från Skeppsbron Gamla Stan. Gammalt objektiv på ny kamera ger skärpa där man vill ha den och oskärpa bortom, Zeiss CY 35/1.4.
Had it for four years now and I still find lines as beautiful as ever. A nice shot from Old Town Stockholm. Credits for the blurry background goes to an old Zeiss CY 35/1.4.