The 1st word should was supposed to be blackbird
Haha…I think I mentioned 3 miles of vacuum line being on imports of a certain 80’s vintage. The honda CVCC I think was an offender…hell many of those imports back then had vacuum lines like you would not believe. Ive often wondered what on earth they did or how anyone ever designed those things…and how they managed to be as trouble free as they did also. Thank Goodness they used very high quality line tho… You should see some of those things…so so many lines all on a carbureted engine too…a total nightmare if you ever disconnected them enmasse.
Blackbird
When automobiles were young 6 volts was the operating voltage on most/all automobiles and I would guess that the amp draw on a wiper motor might be well in excess of the charge rate of the generators of that time. And the auto industry hates change. Like drum brakes, the Big-3 hated giving up a system that they had totally amortized the machinery to manufacturer.
You have a point there @“Rod Knox” I hadn’t considered that. Perhaps there were concerns of the electrical system integrity. HAHA…YES those damn drum brakes refuse to go away… My theory on that is that they probably manufactured Billions of those components and need to find a way to use them up…I cannot rationalize it to myself any other way I think. Ha…funny
Speaking of 6 Volt batteries. My 66’ MGB had two 6 volt batteries in separate storage locations under the back “parcel shelf” cover. They ran the 6V’s in series to get 12VDC…AND they were POSITIVE EARTH !! Man talk about wonky, I guess its no more wonky than Negative earth…but you know what I mean…just seems very odd to choose that configuration…what on “Earth” could have been the precipitous of that decision?
I don’t see too many 6V batts anymore…not counting the 74’ GE Elec Trak riding mower I just restored for a friend of mine… A FULLY electric riding mower! Electric mower deck…snow plow attachment, roto tiller…chainsaw attachment w long cord…even a WELDER Option! It uses 6-6VDC batteries…and those puppies are NOT cheap either! $100 a pop…seems high but what do I know. These General Electric Tractors are actually a high demand collector item. Whats old is sometimes New again I tell ya!
This guy has the setup for sure…including solar power to charge all those batteries! Talk about cool
Blackbird
Just when I thought I had seen and heard of everyting @Blackbird.
No way @“Rod Knox” …with me around you will never be at the “Heard Everything” stage… I get into some truly Wierd Wacky stuff for sure… I jump in with both feet. Hahaha
Honda Blackbird: My 1966 MGB had the same battery configuration. My MGAs had the batteries mounted on the floor behind the seats. This was done for weight distribution. Did you ever notice the passenger side of these cars sat about 1/2 inch higher? This was to compensate for the driver’s weight (when they were configured to “proper” British right hand drive). Positive earth was probably wonkiness required by the spirit of Sir Joseph Lucas “Prince of Darkness”!
Yes Sir I did notice that !!! I thought I was having an “off kilter” day however @sgtrock21 !! I swore to my Pop that the car looked crooked and he dismissed me.
Yes I knew the batteries were for even weight…but never figured out why Positive earth tho… It really doesn’t matter in an electrical sense…just in a convention mentality. It also matters in a part swapping excersise …you can just throw any ole electrical items in there without paying attention. I wonder if anyone knows the answer behind the Positive Earth setup?
The Prince of Darkness indeed. I think he got a bad Rap though…if you kept your connections clean and tight many if not most of those problems went away…just nobody bothered to do that! Every time I mention my MGB I get upset…not because my brother has it…but because it reminds me of the MGA I could have purchased for 400 bucks…back in HS. Back then I was broke as a joke…and also had Camaro Head pretty badly…so even though it seemed sorta cool to me at the time…I never got to owning it. I can tell you now that I regret it because I have come to appreciate the MGA’s lines much more as a semi sane adult. It also put a hurt on me because as I was cruising round my block one day…I spotted the new owner pulling it out of the guys driveway. DOH !!! That stung even then…it downright hurts now. Oh well… What can you do?
Blackbird
Re positive ground, doesn’t current actually flow negative to positive.
Blackbird I never knew that any cars had positv ground. but did know that mack trucks had it in the 50s @ early 60s. If I rememeber right some the internationls did also. I do rember many drivers killing brand new cb raidoes by hooking them up to what they thought was neg. ground
It seems like positive grounds were more common in 6 volt/generator equipped autos. Does that sound right? If so, maybe there’s some kind of design advantage to a positive chassis (vs the typical negative chassis ground) when the electricity source to run the car’s electrics and charge the battery is derived from a generator rather than an alternator. I can’t think what that would be though. The weak link in a generator is the commutator. The metal tends to wear away and the brushes tend to gunk it up. Maybe all that is worse with a negative ground. Just a wild guess.
Getting back to the vacuum lines … another question, it’s clear that a leak in a vacuum line sourced from the intake manifold will cause lean idle mixtures and probably lots of idle problems, stumbling, stalling, etc. But what about a vacuum leak in a line sourced from the carb? The vacuum advance for example is usually sourced from the carb. What would be the effect on idle mixture and off-idle performance with a vacuum leak in that line?
Hey you might have something there @GeorgeSanJose I forgot to think about the Genny… Then again…even if I think about the Genny it doesn’t make me think anything else so Im coming up with nada on this one. Looks like I needs to do another web search out of curiosity. Wont be the first or the last time I had to do it…in fact I do it all the time…who am I kidding. Haha
Blackbird
There’s some claims about wiring insulation being involved @“Honda Blackbird” . Apparently wires in cars in days of yore weren’t insulated with highly insulating plastic PVC, but with a sort of cloth material. And when that got wet it would conduct a little electricity, and that current flow would cause corrosion between the wire and the chassis part it was touching. Not sure if the corrosion problem was more in the copper wire on whatever chassis part it was laying across. The wires on positive chassis cars would tend to be grounds to complete the circuits. Apparently there’s less corrosion between a copper/cloth/steel current-carrying sandwich if the copper is a lower voltage than the steel. Maybe has to do with the electron configuration of copper atoms vs iron atoms.
It seems we’ve enjoyed this topic in the past
http://community.cartalk.com/discussion/2132988/positive-ground-electrical-system/p1
I’m doing some experimenting, following some of the ideas in posts above, the goal to minimize the vacuum line spaghetti. Right now the only vacuum lines I have hooked up are the two to the transmission modulator, one comes from the intake manifold, one from the carb base (above the throttle plates). As shown in the diagram, except no thermal vacuum switch being used. All other vacuum lines are disconnected and plugged.
I tried using no vacuum hook-ups at all, but I quickly discovered if I didn’t hook up the transmission vacuum inputs, the transmission wouldn’t shift properly. So the way it is now the transmission is shifting fine, and the engine is running great. I don’t even have the vacuum advance or retard hooked up, around town at least I can tell no appreciable performance difference. I still have the distributor centrifugal advance of course. I think I’d notice if I didn’t have any advance.
One problem though w/this minimalist configuration: The engine doesn’t start right up like it did before. It takes around 5 seconds of cranking before it jumps to att’n and starts running. Before , with the full vacuum hook-up, it took maybe 1/2 second tops to pop into action. Any ideas what’s causing that? I’m thinking it may have to do with the advance/retard. I seem to recall on old Fort Model T’s, there was a lever the driver used to advance and retard the timing manually. Does anybody know which direction the driver put it to start the engine? Advance? Or Retard?
There was a critical issue with Model T timing when cranking. If the timing was even slightly advanced the engine would likely take a counter clockwise turn and send the person pulling the crank to a doctor. Ideally the timing should be 1* after TDC.
I suspect that somewhere in the effort to diagnose/correct the problem that the choke/fast idle cam have been altered amd are not being engaged when cranking cold. But you might try pumping the accelerator twice and then holding it at half throttle to see how quickly it fires up.
Years ago I recall tuning up Fords and when the customer picked up the car I put the key in the ignition and asked them to reach through the window and crank it. When the engine immediatley started the customer was satisfied with the work. But that was long ago. Now everyone expects that from 20 year old cars with 200,000 miles on them.
Retard a little best to start on the Model T? hmm … One thing that’d be easy to do is re-connect the distributor vacuum retard. That connects straight to the intake manifold, so it will likely yield a retard of around 3 degrees at start up. I’ll give that a try. And will experiment with the accel pump etc as suggested. Thanks.
The Model didn’t have vacuum advance. It didn’t have a distributor. Spark was advanced and retarded with a lever on the steering column.
I tired tried your idea @“Rod Knox” of pumping the gas pedal 3 times to squirt some extra gas into the carb then press the pedal halfway down before turning the key. The result is the same as if I just press the gas pedal enough to allow the choke plate to close, then turn the key without pressing on the pedal at all. <-- That’s the method that worked best before. What happens now, either way, is I hear a noticeable “pop” as soon as it starts to crank, making it seem like it will start right up, but then it conks out. It sounds like it is somehow a little flooded or overly rich. Once this “pop” & conk happens, pressing the pedal almost to the floor and 5 seconds of rr rrr rrr cranking, it starts up ok then.
One thing that occurs to me, the cleaning process removed the lube from the choke linkages. I usually sprayed a little WD 40 on that stuff when I removed the air cleaner. Maybe something is sticking a little with the WD 40 removed. I did check where the fast idle screw hits the fast idle cam against the instrucitons which came with the rebuild kit. On cold starts it hits near the top of of the cam (for the fastest possible idling), there’s a “C” stamped there, when the engine isn’t running and the choke plate is completely closed. Once the engine starts the choke pull-off opens the choke plate slightly and that causes the fast idle screw to move to a lower position on the cam, where there’s a “V” stamped.