Hi arcturus,

Like the star named Arcturus?

Do I guess correctly that you have already had your 1961 Volvo PV544 B16 Sport tested for emission before? And you passed these emissions standard you and alschnertz reference?

Or are these emissions standard being levied against your 1961 Volvo PV544 B16 Sport?

Do you have any relief from these standards at all? You simply can't label your 1961 Volvo PV544 B16 Sport as antique or historic? I'll guess in Spain and elsewhere E.U. that cars labeled antique or historic, should such a provision exist in some motoring law, the classification limits how many miles you could drive annually?

Though you may have already, you may want to research auto enthusiast sites in Spain or the greater E.U. that list these same set of issues for folks with Volvos or other auto makes of a similar vintage.

Anyhoo, as you write, with Points plugs tappets properly set ...

Can you at least perform some sort of emission analysis to see if your 1961 Volvo PV544 B16 Sport is anywhere near the emissions standards at the tail pipe? It would help us to know how far off and in what way you are from passing the emission standard to which your 1961 Volvo PV544 B16 Sport must comply.

A 1961 Volvo PV544 B16 Sport, from the factory, is a clean burning automobile, for the day, with the exception leaded gasoline may be required for the valve seat lubrication. I guess all automobile gasoline fuel is now lead free across all Europa?

How is the engine compression? Full battery with all spark plugs out either cold or warm. If some variance, a leakdown test?

You say your points are good. Is the ignition coil producing a proper spark that is hot enough? Is your charging system producing proper power and the battery fully charge? Electrical power weakness may mean reduced spark and a richer (higher CO, CO2, and unburnt hydrocarbons). Verify the wire harness is in good condition and that all connection, terminals, and all connections to ground (or earth) are a solid bond. An electric multimeter allows you to perform continuity, resistance (Ohms), and voltage checks.

You will need to be careful, yet newer, hotter, or higher performance spark plugs, can help. Use the proper spark plug gap.

What carburettors due you have? One or two? I'm out of my element as I've not had my hands on an OHV, with carburetter, redblock Volvo engine in quite sometime.

I'm unsure, yet you may be able to vary dash pot oil. A high viscosity may dampen fuel enrichment during acceleration from opening the throttle. Though not all carburettors have dash pots with dash-pot oil reservoirs (like newer Weber carbs, I think, yet this is not 1987 anymore.)

Can you vary jet size on the carburettors? Smaller jets to lean the fuel to air ratio or larger to enrichen it.

If carburettors, the chokes fully closes, or if manual choke, the choke indeed fully closes, as the engine is warms up?

And the carburettors on your engine work fine and don't leak?

Could you try a different emission-reducing carburettor? Weber used to make these.

Change the engine oil with new filter if the engine oil is old and dirty. Does the B16 have a crank sump vent to the atmosphere, or are the combustion gasses from the engine oil sump burned through the engine as with a positive crankcase ventilation system?

Use a higher octane automobile gasoline fuel (petrol). Octane is the ideal petroleum hydrocarbon distillate for your B16 engine. The higher the gasoline octane rating may result in reduced emissions.

Some may use gasoline with ethanol as ethanol blended with gasoline may reduce emissions. (Contrary to using a higher octane fuel.)

You may have fuel additives at your auto parts store that may make dubious claims to reducing emissions.

You may want to clean the air intake system by dismantling it to verify the air intake manifold is not clogged with hydrocarbon vapor condensates.

If you make sort frequent stops, and rare if ever long run driving on the highway, use a cold thermostat in the engine, use mineral oil (not synthetic like Mobile 1) engine oil, as unlikely as it is, deposits can form on the air intake valve around the stem where it meets the valve body on the upper side around the round valve stem. Such deposits greatly diminish engine efficiency. I'm uncertain if fuel additives like Techroline can clean away, through adding to your gas tank and merely driving.

Is the engine coolant thermostat the current temperature (meaning, not too cool of a thermostat). An engine coolant thermostat that is rated at the higher of temps in the temperature range, the engine in your 1961 Volvo PV544 B16 Sport can also reduce emissions.

It would help if you could check the emission levels with each improvement you may want to make to see if you could meet or exceed the emissions standard.

Lastly, if your 1961 Volvo PV544 B16 Sport runs well, and can't pass emissions, yet the exhaust gases out of the engine are acceptable as input to a temporary catalytic converter, with some research and great expense, and with modification to the exhaust, where the header pipe out connects with the reat of the exhaust piping. Important that the exhaust gases are not too lean nor too rich! Watch that choke! Also, the exhaust upstream of the catalytic converter must NOT have any leaks! Just be certain any catalytic converter fits and the exhaust piping can carry the catalytic converter weight.

And after you pass the emissions, remove the catalytic converter and replace with a pipe section.

All of these ideas in no real order. I guess easiest and cheapest first to ever harder and more expensive until you pass emissions and do so again each time successfully.

Questions?

Hope that helps.

Thank you.

MacDuffy's Tavern and Tapas
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