Spinneyhill

The Master Parts List shows only split rivets #104449 to hold the lacing to the radiator shell - no glue. Those rivets are oval head split rivets in black enamel finish, 9/64 x 3/8". This is the tool to seat them properly. If you just flatten them, the legs break off.

Fuel expands when it heats up so in the same "charge" of fuel there is actually less fuel and thus energy when it is hot. Air also expands with heat so you get less oxygen in the mixture.

Is the aluminium stiff enough to hold the boring bar, to achieve the accuracy you are after?

1930 DC is the same. The split rivets are supposed to be black enamel finish.

Oil pump.

AC list a type 588 for the 6 cylinder Chryslers to 1952 and a type 590 for the 8 cylinder cars 1939-50. So far I haven't found what they look like.

Sorry Sir, Graphite is the most noble (cathodic) and at the top (or bottom) of the galvanic series. https://en.wikipedia.org/wiki/Galvanic_series http://www.designbyinitiative.com/files/8514/2711/8760/Galvanic_Table.pdf https://corrosion-doctors.org/Definitions/galvanic-series.htm

Wet it with penetrating oil or something and wipe off, gently. Look at it under variable directions of light and you will see what it says, roughly. In 1930 they were printed or screen printed or something on tin plated steel and punched out - on mine, you can feel the ridge around the back from the punching die.

Also check the oil for dilution by fuel. A leaking diaphragm can let fuel into the block.

Graphite = Carbon is the dissimilar metal. It is at the bottom of the galvanic series so promotes corrosion in any metal in contact with it in the presence of an electrolyte.

Yes, I have one for use on my 1939 Studebaker front spring.

I hope you keep that grease moist, to exclude any dampness from the graphite-steel interfaces.

As the powder coat wears, it will produce a fine abrasive dust. Good for wearing the powder coat then the springs. As for graphite, no way. Unless you keep it moist with grease (NOT oil, which will attract dust) it will promote galvanic corrosion.

Yes! Here is a paragraph from the wikipedia entry on John J. Mooney (the bold bit is mine): " As President of the Environmental and Energy Technology and Policy Institute, Mooney has worked with the Partnership for Clean Fuels and Vehicles of the United Nations Environment Programme to help end the use of leaded gasoline throughout the world. As of 2002, there were 51 countries in Sub-Saharan Africa in which leaded gasoline was still in use.[6] By responding to issues of valve seat recession, and showing that lead in gasoline did not help solve the problem, Mooney was part of an effort that had 50 of these 51 countries in Africa ban leaded gasoline by the end of 2006.[1][7] " Here is the report of the PARTNERSHIP FOR CLEAN FUELS AND VEHICLES, VALVE SEAT RECESSION WORKING GROUP: https://archive.epa.gov/international/air/web/pdf/vsr-finaldraft.pdf

My reading is that valve seat recession started in some engines after unleaded gas came into use. The octane boost of "ethel" prevented pre-ignition. When it was removed, the octane of fuel was reduced and flame front speed increased. This is what was hard on the valve seats. As for a layer of lead, addition of ethylene dibromide and ethylene dichloride prevented the layer of lead being deposited - it was a serious problem before those chemicals were introduced. The byproducts, which come out in the exhaust, lead chloride and lead bromide, are highly toxic. This is what wikipedia says about it, with references: "Valve wear preventative It is a common misconception that 'Tetraethyllead works as a buffer against microwelds forming between the hot exhaust valves and their seats.[14]' Once these valves reopen, the microwelds pull apart and leave the valves with a rough surface that would abrade the seats, leading to valve recession. When lead began to be phased out of motor fuel, the automotive industry began specifying hardened valve seats and upgraded exhaust valve materials to prevent valve recession without lead.[15] Microwelding of the exhaust valve and valve seat is now thought to have occurred due to the increase of flame front speed when the switch to unleaded came about. The increased combustion pressures caused 'micro welding' in older style motors that had the valve seats machined into the cast iron head. Retarding the timing of the engines reduced the combustion pressures and proved to be an effective short term measure in the switch to unleaded fuel. The long term solution was hardened steel valve seats.[16] "

It is safe to say that NO ENGINES were designed assuming tetraethyl lead (TEL) would have any effect on valve lubrication. That is a myth. TEL was purely and only an anti-knock additive. It was noticed, after ethylene dibromide and ethylene dichloride were added, that the carbon deposits in the combustion chamber are less than without "ethyl" being added. The carbon may be slightly harder than without "ethyl". In the cooler parts of the chamber, they are greyish in colour, while in the hotter parts, such as the exhaust valves, they are reddish, but are easily brushed off with a stiff wire brush.

How did they harden the valve seats locally?

With any link, just hover over it and (in Windows) look at the link at the bottom left. Does it look like what you expect for what it purports to be? If not, don't go there.

No Sir. Tetraethyl lead was introduced in the '20s as an anti-knock additive. It was found to be a suitable cheap additive by GM laboratories in 1921. It "acts by controlling the combustion or burning rate of the petrol when in the cylinders of the engine. In other words, it prevents undue rises of pressure over small crank angle movements - that is, when the piston is at, or about, top dead centre. Thus, spontaneous ignition of any part of the petrol-air charge is avoided..." from the Service Station and Motor Mechanics' Manual, by George George, 1940. It became available on 1 Feb 1923. Increases in compression ratios followed! It was noticed in the early days of its use that it had a harmful effect upon the combustion chambers, pistons and valves of engines, due to the deposition of metallic lead. After considerable research, "ethyl fluid" was modified to be 61.69% TEL, 26.88% ethylene dibromide, 7.55% ethylene dichloride, 2.82% kerosene to dissolve 0.12% dye, plus some impurities. This was in 1940 of course. The kerosene had a slight lubricating effect too.

Here is a 1933 De Soto for sale at SM Classic Cars:

Hover over his userid. He hasn't been here since May 14. Quote something of his or send a p.m.. The forum will send an email then.

The man still hasn't been here since Jan 25. Hover over his userid and it will show you. Quote something of HIS (not yours) or send him a p.m. Both ways the forum will send him an email.

My impeller was worn or eaten away. The shop brazed it back to size.

I posted on Sept 21 in...

LoL! I have the Studebaker version: Significant Parallels. It compares features of the 1935 Studebakers with models by other makers in similar price brackets. The interesting part, to me, is what they show was "better" in the day, which is often not what we would call "better".