Mileage for my '76 244 GL?

Hi,
I own a 1976 244 GL with 380 000 kms on it. It runs well and the body
is in great shape. One concern, however, is the fuel economy. I use BP
Ultimate 98 Octane fuel and do about 50/50 city/highway driving. My
mileage is 14.02 Litres/100 kms with a standard deviation of 0.94 . It
seems too high. Are other owners getting this kind of performance?

Bruce Backman

PS - The motor was replaced with a new one from the factory at 320 000
kms.

 

Why are you running 98 octane fuel? That's not a high compression engine is
it? Try 87 or 89 octane, your economy will likely go up noticeably. Unless
the scales are different, we can't even buy 98 octane here in the US, the
highest I've found commonly is 92, and that's sufficient to run 16 psi on
the turbo without pinging.

 

In some places, octane is listed by Research Octane Number (RON), which
is different from the US octane listing of (RON + MON) / 2. The RON is
higher than the US octane number for the same gasoline.

 

This is correct. In my Swedish Haynes manual, the B230K-engines are
specified to use 95 RON (UK 4-star or "Premium Unleaded"),
the B21E- and the 75-76 B21A-engines are specified to use 91-93 RON (UK
3-star), and the others are specified to use 97-98 RON (UK 4-star).

If this applies to US-models, I do not know.
Anyway, the B230K is decribed as "Herron Head" and made for unleaded fuel.

- Jan Rune Bjorkelo -

 

A 960 recommends 91 octane in NA, our old 740GLE recommended 89, I believe.

 

Thanks to all who have responded to my post. In answer to the question
"why am i using BP Ultimate 98 Octane fuel"... my mechanic, who works
exclusively with older Volvos suggested it. He says that it improves
the fuel consumption and lubricates the engine 'top end' as well as
cleaning the injectors. By the way , his shop is "Evolv Volvo" and his
name is Jim. He is located here in Adelaide, South Australia. Before I
took his suggestion I did a trial run and ran a few tanks of regular
unleaded (92 Octane) through the engine and then I switched to the
Ultimate. The difference was significant, smoother acceleration and
better fuel economy (almost 1 litre/100 kms). But back to my original
question, is 14.02 +- 0.9 litres/100 kms reasonable for my B21a engine
given that I drive 50/50 city / highway? My best was 12.3 l/100 km and
my worst was 15.6 l/100 lm . I know the Volvo is a heavy car and can
be considered slightly underpowered but I think I should be getting
better than I am!
Bruce

 

I think this sounds a little high. I had a b19a (which is a b21a, but only
1986cc instead of 2127cc), and it used about 10l / 100km on highway/city, I
think.
I never had the chance to doublecheck this, though. It might be the engine
used a little bit more, but 14.02 sounds a bit high.

- Have you checked the spark plugs? How do they look?
If they are very old, replace them. This could help.
- How is the air filter?
Does it look clean, or does it give the airflow a hard time?
- I think my Haynes manual mensioned the needle (inside the carb.) could be
"worn out",
or wrongly adjusted, and therefore increasing the usage.
- If you open up the carb. there is a rubber membrane inside.
Hold it up against the light, and if you can see through it somewhere,
replace it.
I don't know if this will affect the usage, but it can certainly make
the car more difficult to start,
and it can make it idle badly.
- I have heard of cars where the brakes have been constantly on, thus making
the engine use more.
Check this out.

- Jan Rune Bjorkelo -

 

You mention something about injectors? That means Jan Rune's suggestions
on carburator tricks may not apply to you. The 240 cars sold in
Scandinavia in 1976 mostly hade carburator engines, while those in the
US hade fuel injection, and in California even with catalysts.

I had a '84 245 with B21A engine (carburator), with 4 speed manual
transmision. It consumed about 9 liters /100 km on the highway (decent
driving). I may have struck 14 liters on one tank in winter with mostly
city driving, but as average it sounds high. Do you have manual or
automatic trans? Air conditioner?

In adddition to Jan Rune I would like to add two things:
How's your tire pressure? Make sure you are not low. Better 10% above
recommended than below.

Have you run a compression test? That's a simple thing. If the cylinders
deliver good pressure your engine should be in good shape, if not you
may need a valve or ring job.

If I understand your posting correctly your engine has only gone 60 000
kms. In Volvo B21 terms that is equivalent to "new".

 

Thanks Gunnar for your suggestions. I will check the tire pressure
although they are all recently new and should be ok. And, yes, the
engine has fuel injection and has only travelled 60 000. I have an
automatic transmission but it was recently (4 months ago) rebuilt and
seems to be doing the job -- then again automatic transmissions are
like a mystery to me . The a/c has long since packed it in so
there's no drag there. I will ask Jim , my mechanic, to do a
compression test (wet and dry) to see if there is any problem with
combustion.

thanks to all who replied. I appreciate your time .
obsessive Volvo driver
Bruce