Why is this so?

woofa.express

woofa.express

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images.jpegWhy is this so?

I have no claims on being a mechanic. But with the correct tools I am capable of becoming a mechanic’s bootlace.
Example. With a nu-Rex timing wrench and the new points gapping tool I can get both the timing and points gap correct, as well as my friend Henry (the local Australian one) who came off the production line the same year as my A.
But a problem has launched itself. The points gap was a little close and I have perhaps made it a little wide. The acceleration is improved and the comfortable cruise speed is a little faster. But the points gapping has caused the timing to become more advanced in both the start and cruise. The cruise can be compensated for with the timing control lever.
Another problem I have, and this was prior to adjusting the points, is at lower speeds the motorcar can become “jerky” with momentary hesitation. Question, is this electrics or carburation? Please can you readers steer me in the direction to rectify this. And in anticipation, thankyou. Gary.
 
The timing is adjustable so that the operator can change it for changing conditions. It sounds like it was too retarded when the gap was smaller. I don't have any experience with the Nu-Rex timing wrench but I would adjust the gap to 0.020 and then set the timing a little more advanced with the wrench. As you say, you can retard it with the lever if needed, like for hills. If the ignition is too retarded then it can cause the momentary hesitation or it could be the carburetor.

Adjust the timing with the lever for the best performance. Advance it until there is no additional improvement with more advance then retard it one or two notches. If cruising you may want to advance it a little more and if under heavy load you may want to retard it a little. It does not hurt for the ignition to be slightly advanced when starting as long as it is not fully advanced. Just push the lever all the way up when starting.
 
If the car was just started and you start to drive, you should open the gav 1/2 turn. I live in the mountains and when I leave I immediately have to go up a grade so I will set the GAV at 1/2 to 3/4 open to stop the lurching.
Dan
 
I've not been impressed with the Nu-Rex timing lever.
At least for me I get better timing in terms of idle and acceleration setting it up the way Marco advocates on his page
 
With less point gap, the points open sooner, thus changing the timing and coil dwell. More dwell should develop a hotter spark (more voltage to the plugs). This is rarely felt during driving conditions. I imagine this is the same down-under but it could be the opposite. -:)
 
Jim Brierley said:
With less point gap, the points open sooner, thus changing the timing and coil dwell. More dwell should develop a hotter spark (more voltage to the plugs). This is rarely felt during driving conditions. I imagine this is the same down-under but it could be the opposite. -:)
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Good one! :)
 
My brother in Law lives in the coastal town of Rainbow beach where fishing is popular. He, like many have aluminium fishing boats, many suitable for off shore fishing. He spoke about one boat owner who secured his boat (at home) by chaining the trailer to the concrete. As a consequence his aluminium boat was totally destroyed by electrolysis. Destroyed beyond rebuild and was rehoused at the rubbish tip. Well so to speak.
Why was this so? Steel or components in the concrete? Or a shorting battery creating a small current?
I am curious because many aeroplane owners don’t shed their aeroplanes but tie them down to in ground pegs or to pegs set in concrete. Like the boat, aeroplanes are made of aluminium or infact duralumin which is aluminium with a small component of copper and magnesium, but never the less substantially aluminium.
I sent the above to a buddy, an industrial chemist.
Here is his reply.

Aluminium is corroded by high pH, or alkalinity. Cement (depending on mixture and variety) can be very alkaline.

Queensland is our north east state. Known to folk abroad for the “Barrier Reef” and locally for it’s dry red interior. It is 2.6 times larger than Texas. But not quite as wealthy.

 
J Franklin said:
Reguarding the boat, I wonder if the tiedown chain gave a path to ground and did encourage electrolysis.
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Hi Mr Franklin. I don't fully understand your comment but yes the chain was the conductor. cheers, gary. and I guess you could well say his boat was stolen anyway.
 
How did the cement get to the boat?

A boat trailer has rubber rollers so the boat is insulated from the trailer.
As the trailer only was secured, maybe someone swapped the pristine boat for their rusty one.
 
Aluminum and ferrous metals like iron and steel have to have external finishes applied to resist the corrosive effects of salt sea air and water. Washing the hull with fresh water after immersion will help stave off corrosion but the finish has to be maintained to prevent the corrosive liquid from coming in contact with the metal. Salts, acids, and bases form electrolytes when mixed with water and any electrochemical action will cause the surfaces of reactive metals to form more stable oxides when contact is made with any form of electrolyte.

There is no better car to learn mechanics on than an old Ford. The simplicity allowed almost anyone to maintain one in good condition.
 
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updraught said:
How did the cement get to the boat?

A boat trailer has rubber rollers so the boat is insulated from the trailer.
As the trailer only was secured, maybe someone swapped the pristine boat for their rusty one.
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I apologies to you updraft, I did not unintentionally ignore your question. The boat was chained down to the concrete in his back yard. On a trailer with rubber runners however it would have had a ratchet to pull it up on to the trailer with. I didn't investigate whether or not his boat had been substituted.

My chemist friend said the following.
Aluminium is corroded by high pH, or alkalinity. Cement (depending on mixture and variety) can be very alkaline.

He went further to include an article on just that if you are interested, as follows-

https://www.concreteconstruction.ne...-does-contact-with-aluminum-affect-concrete_o
 
Your chemistry friend is correct when referring to the powders that make up concrete but concrete that has been mixed, formed, and set to complete cure is basically inert.

Quick lime is the most reactive form of one component of a particular form of concrete or morter. It also becomes inert after it is mixed and cured. Dissimilar metal corrosion it where two different reactive metals such as steel and aluminum are joined together and one reacts adversely with the other and speeds up the corrosive effects. Another type of corrosion that is a problem with aluminum is intergranular corrosion where the bond grains of the aluminum actually react adversely with each other which causes the metal to split apart between the grains of the metal. Certain heat treatment procedures can exasperate this problem and especially in forgings but it can affect aluminum sheet material as well. The metal just flakes apart.

This corrosion can happen on any aluminum structure that has no protective coatings. Boats and aircraft are no exception. It can happen to any structure that is left to the elements of it's environment. The closer to the coast, the faster the reaction.
 
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