Fuel consumtion and engine performance in general

[suzukicarrybeginner]

Hi;

I have just bought a 1995 Super carry with a 970 engine and I am bit appaled by the economy of the thing. I did the first tank of petrol, mixed driving (motorway avg 55 mph and London city driving 50/50) I used 32 liter fuel to do around 360 km. That's terrible if you ask me, one of the reasons for getting this was because it had a small engine. So, what can be going wrong here?

Now, I am planning to do a compression test to see if there is a general performance issue and I am thinking that perhaps cleaning the ports (its done 85k miles), making sure the carburator is not taking in false air would help?? But work is work and I would rather not do this.

Also, I could suspect that there is some sort of issue with the petrol pump maybe overfeeding the engine, again, I dont know as I just got the car a few days ago.

Any suggestions as to what the problem is? And what should I expect to have as a good mpg, I think right now its about 35 or so.

Looking forward to your replies
Cheer, Mark

[newsavedone]

Greetings! I have a Turbo 660 EFI automatic and it get about 25 MPG here in Cebu.
55 MPH is a bit fast for these things I think. NO crash protection if yours is like mine.
Manual transmission is fine for country and hill country, but automatic is what you want for city, and slow down!
Clean/ change your air cleaner / plugs, and the timing belt is due at 100000 KM. Good luck.

[suzukicarrybeginner]

Absolutely, I look forward and all I see is road, nothing between myself and impending doom Have vivid pictures of me having the clutch pedal cut away with me trapped in the car. Anyway. I really like this car though, I'm gonna look into getting the fuel consumption down, ill take a look at the plugs and filter in a mo and see if they are looking ok and do a compression test while im at it.

[newsavedone]

Greetings!!!!
You sound like someone who is like me. Completly out of there mind! I pray you keep safe, and solve your problem. Keep in touch, I will try to find about your ride, 970, and what is the norm. Take care, Roger

[suzukicarrybeginner]

Cool, nice to know i'm not the only nutter out there.

Nothing to show, compression was about 8:1 on every cylinder (it's meant to be 8.3:1 if I have the right engine data), plugs were nice and brown, also checked the choke to see if it stuck but nothing. Must admit it can be useful having the engine under the seat when checking the choke pulley haha. Airfilter was also OK, gave very little resistance compared to no filter.

I got a new set of fronts today as I had a puncture and I can feel that has reduced the cars rolling resistance (old tyres were crap and not at right pressure)

Also, front right brake is sticking a tiny bit and I will clean the caliper this weekend and get that sorted.

BUT, nothing above is justifying a very low MPG for a 1.0 engine. I have had 2.5 that were more fuel efficient and I dont drive hard.

I'm on a mission here, next area to look at is the emissions of the car to see what the output is and if there is a carb issue... The saga continues

[Karu]

I have two Super Carry's, one a 1985 and the other a 1987. I don't know where you are, I am in Australia, but it sounds as though they are the same as yours as the engine under the seat tells me. The 1985 has traveled 268,000 kilometres and my 1987 has traveled only 8000. I have just returned from a trip in my 1985, covering 1720 kilometres in 22 hours. The F10a is an amazing engine, considering the 268,000 km it didn't use any oil or water, not bad when you think that the wheels turned around 1,078,200 times. With plenty of room to sleep two I don't know why people need large cars. And when you realize that all the many trucks I shared the highway with, those tyres only did half the revolutions over the same distance makes the Suzuki all the amazing.

But of course this thread is all about fuel economy and that is where I am leading. Whether it be a Carry that has traveled 268,000 or 8000, the fuel average is about the same, although average is difficult because sometimes I can travel huge distances on little in the tank and other times very little distance but, it happens with both vans. My 1985 will often travel 16.4 km per litre and sometimes, like on this trip it will get down to a disappointing 12 km per litre but, and newsavedone is going to love this, it wasn't unusual for the tiny van to get a mind of its own and decide to do 125 kmh, and still with plenty of room under my right foot (it has started doing this recently, it used to have a top speed of 110 and now without any foot movement it becomes unusually quite and surges forward passing everything on the road and what is more surprising is how safe it feels at this speed. And it only has 23.2 kilowatts or if you prefer 30 hp at the rear wheels. Yes, I had it dyno'd). So, while I am not happy about the high fuel usage for such a small engine and vehicle, I wouldn't trade it for anything.

I'll put it this way, Ford has just released a diesel car that uses less fuel than the Toyota Prius. Sure, it sips something like 3.7 litres per 100 kilometres and here in Australia it sells for $25,000 big ones but, at the current cost of fuel that will fill my Carry's tank for the next 250,000 kilometres and the new Ford owner has still yet upon purchase to put fuel in his/her new car. Who's laughing loudest!

[suzukicarrybeginner]

OK, so I can tell from the last reply that the 95 carry should be capable of 12-16 km pr liter, which sounds reasonable to me.

Now I have been driving I am noticing sounds, like when I have been on the throttle for a while and let go, the engine carries on for a little bit and when throtteling on and of while stationary it gurgles on engine decelleration.

Something tells me that can be the engine timing? Or that the carbs are leaking false air? Any idea?

[Suki Garry NZ]

I have the same problem. I've had my '91 Carry F10A 5 speed van for 18 months. It uses the same amount of fuel. 32 tank and around 330-360kms later and it's empty. This little van has done my head in as to why it uses so much fuel. I've had the head off. Cleaned the ports up, reseated valves, rebuilt the carb to no avail. I even put an 1" 1/2' SU carb on to see if that would make a difference, but it still used that same 9-10ltrs per 100kms. Sometimes wish I still had my old company car, a 2005 BA Falcon 4.0ltr six cyl with 185kw that had the same fuel consumption.

Being a mechanic for the last 9 years I know that commercial vehicles use more gas. The profile of the cam shafts are different and are designed to produce torque. Torquey engines suck more fuel. That is the one thing I love about this van. Regardless of how much weight I put in it, (and when I say weight I mean it, I put my '94 Honda RVF400 and a full tool and spares in when I go to the track) it still uses the same amount of fuel, and still drives exactly the same because it has alot of torque for a 1000cc engine. You could always look at have the cam profile changed to a profile closer to that of a Swift.

One thing I noticed on mine, which is the next thing that I am going to do, is that these engines are known to flog out the rocker shafts, but they only flog out one side, due to the load only being on one side of them. You can turn them over. I was looking under my seat today and this is going to be a bastard of a thing to do whilst the engine is in the vehicle, and a couple of holes on the shaft need to be counter sunk on the opposite so that you can turn it over, any local engineering shop should do it for you. The reason for this is that if that shaft is badly worn it could change the rocker arm ratio causing the valve to loose lift (not open as far). It may explain some of the poor running mysterys.

I've had 1000cc vehicles before. One being a 1979 Toyota Starlet with a 2K engine. 28ltrs to fill and 750kms to a tank. I know I'll be pushing shit uphill to achieve this fuel economy with an F10A engine but I'm a persistent little bastard and will find a way to get it down to around 7.5ltrs per 100kms. One thing I did find that would achieve this is a kit to put a K series Toyota engine into Carry vans. Might be worth looking at?

[Karu]

It seems that the best I could get from my 2 Super Carry's was 12 km per litre. One has 8000 km since rebuild and the other 269,000. I love the F10A, but admit that the fuel usage bothers me. I would like to know more info about putting a Toyota K series engine in. I always plan, but never succeed, in trying to see whether any Subaru engines will fit.

[Suki Garry NZ]

I've looked back over old files and realized that I miss read it. It is a conversion kit for bolting a Toyota K series engine up to an F series gearbox but unfortunately it was to put a K series engine into a SJ410/Samurai. You could still do it but you would have to modify the engine to allow it to lay over and make a new intake manifold.