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Hi Spook, Re. the Bosch in-tank main fuel pumps for 940s.
According to the Volvo Pocket Data Book (which agrees with my understanding), these were used only in the 1995 models (1995-on 940 in non-North American market, while in other markets it would be '95-'97), while earlier 940s with B230F Regina used a different single main in-tank pump and all other eariler B230F/FD/FT and B234F with Bosch injection were an external main pump with an in-tank pre-pump, similar to the 740s and 240s.
Yes, I see what you're saying about 1995 fuel pump specs from the Pocket Data Book:
o For 1995-on B230FD NA the Bosch p/n was 0580253033 (Volvo p/n 935418) with a pump capacity of delivering 130 litres/hr at a system pressure of 300 kPa making for a draw of 6.5 amps at 12 volts at 20 degC (room temp).
o For 1995-on B230FT turbo the Bosch p/n was 058453037 (Volvo p/n 9136605) and the same specs for delivery under the same conditions.
I note in pics on websites that these are identical looking pumps, also they appear to mount the same on the sender barrel. Despite notes I may have had and in the FAQ, it makes sense to me and I'm now working under the assumption that all 940s that got the larger 73 litre tank used the same longer barrelled fuel pickup/sender assembly. Whether the pump mounting brackets are slightly different is another matter. I've had both sender units out of my '95 940 NA and turbo and my recollection is that they were the same and used the twin coil rod fuel level sender (the one with the butterfly contacts that can wear out as I described), rather than the single coil rod design used in the earlier shorter-barrelled sender units. And, yes, a 740 sender fits the larger tanks for collar size and thread, but the dash gauge will read extremely incorrectly and the bottom 1/4 of the tank will not get used -the end only partially extends into the central anti-slosh bucket and will suck air easier accelerating up or down hill with a 1/4 full tank.)
So that now begs the question, why two different pumps for NA and turbo that externally look identical and appear to have the same specs? (Also priced very close in listings.) About the only difference I'm aware of between these these two fuel delivery systems is the injectors, with the NA injector delivering 185 cc/min and the turbo injectors delivering 300 cc/min (the 16-valve B234F is in between at 214 cc/min). The fuel system pressure is the same at 300 kPa (both use the same pressure regulator). So, as much as the bench specs are the same for the two pumps and unless there is an external physical difference (which I maintain there isn't) then all I can assunme is that the turbo pump must somehow be designed to better maintain that 300 kPa fuel rail pressure under higher flow rate conditions, hence my note that one is a high flow pump. That also begs the question, why not just use the same turbo pump in the NA engine?
I'll also mention all the fuel pump p/ns in the Pocket Data have since been superseded, so the pump specs may or may not be as published.
To come at this a second way, we can refer to the current genuine Bosch Automotive catalog and their current vehicle selector fitments. For '95 940s, three pumps are listed:
o Bosch p/n 69593 is for the B230F (Volvo OEM p/n 9142044, supercedes p/n 1389449).
o Bosch p/n 69594 is for the B230FT (Volvo OEM p/n Volvo 9142045).
o Bosch p/n 69693 is also listed for the B230FT, which if you do additional research turns out to be 69594 with the filter sock (strainer) included. None of these pumps include mounting clamps or have differecnt connections, which might have explained different p/ns.
Unfortunately, my trail ran dry there for what the differences actually are inside these two Bosch pumps.
To come at this a third way, which now starts to get confusing, we can do a vehicle selector lookup on the various Genuine Volvo dealer distributor parts suppliers (most pull up the same or similar schematics). Using part descriptions, for '95 940 the NA pump is now Volvo p/n 9445444 and the turbo pump now p/n 94338756. Neither of those matches p/n's mentioned above. However, when you lookup the fitments for each of these pumps, mysteriously the NA pump is also listed for turbos.
Things can get even messier when you start to lookup aftermarket suppliers of the Bosch pumps using vehicle selectors and then calling up their fitments, also attempting to figure out the cross references to equivalent Volvo p/n's.
Bottom line, in my mind there's still a bit of unsolved mystery here. Suffice it to say all these pumps appear to be identical in pics and I've found no description that explains the difference. It wouldn't surprise me if both pumps could be used in either the '95 B230FD or B230FT, just that the turbo pump may somehow be more appropriate for the job under demanding conditions. Based on what I know at the moment, if and when I need a new in-tank main pump for my '95 Bosch turbo then I'd use the Bosch fitments, which just happens to be the pumps available at RockAuto and the best buys around.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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