| Author |  Topic  |
rhampsheir
V4 Fanatic
United Kingdom
236 Posts |  Posted - 08 May 2012 : 13:43:17  
| The fuel consumption on my car is getting steadily worse. I am now getting just over 20 mpg.
The car seems to run ok, although it does feel a bit down on power especially up hills.
It starts & idles nicely. Steve (njic) to thank for that. But when I stopped the car for a short time and start it again, it once again starts easily but then starts to hunt. I have set the plugs to 0.7, but when I checked them the first one next to the alternator was black, the rest of them light brown.
It's got a twin choke Solex carb and I have just replaced the fuel pump which was leaking.
What I need is an idiot guide to what to check and in what order.
Thanks |
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96er
V4 Fan
118 Posts | Posted - 08 May 2012 : 16:05:39
| Inadequate timing advance will do that.. (make it run hotter too)
Might you have disabled the vacuum advance when you were working on the pump issue?
Other than that, excessive fuel. |
Edited by - 96er on 08 May 2012 16:06:46 |  |
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rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 08 May 2012 : 16:38:00
| It's not running hot. It usually runs just below normal in town driving unless I am in a traffic jam when it starts to go to about 3/4. When I go above 65 its starts getting hotter, but only just over normal.
I was having problems before I changed the fuel pump. Thought that had cured it because it seemed to only use half a tank after about 90 miles, but the second half seemed to disapear in no time! | |
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Andyinthegarage
V4 Fanatic
United Kingdom
361 Posts | Posted - 08 May 2012 : 21:16:36
| | Following your clutch thread - are you sure fuel inefficiency and power loss on hills isn't slippage? | |
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rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 09 May 2012 : 10:29:41
| | No, it's not slipping, infact it's the opposite | |
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rsimps
V4 Guru
United Kingdom
1616 Posts | Posted - 09 May 2012 : 12:05:11
| | Reset the timing, or just check its where it should be. Then you might have to lean the tick over off. Also make sure your choke is comming off if its the original auto choke (Check the choke flaps are opening fully). | |
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rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 10 May 2012 : 12:24:16
| | Thanks, will check all these things | |
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96er
V4 Fan
118 Posts | Posted - 10 May 2012 : 15:42:07
| When you said it's down on power on the hills, it makes me suspect it's going rich at large throttle openings.
Dirty air filter, too high float level, something hinky with the jets or enrichment system?.....
Choke not opening all the way?
Ask someone to follow you and look for black smoke at hard throttle. | |
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rsimps
V4 Guru
United Kingdom
1616 Posts | Posted - 11 May 2012 : 07:43:11
| | Sometimes the autochoke water feed blocks up, so it always thinks its cold. You will get am idea by feeling the rubber pipe and compairing it to the other pipes. | |
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john-saab
Administrator
United Kingdom
2682 Posts | Posted - 11 May 2012 : 08:07:31
| quote:
Originally posted by rsimps
Sometimes the autochoke water feed blocks up, so it always thinks its cold. You will get am idea by feeling the rubber pipe and compairing it to the other pipes.
That would do it..changing to a manual choke is easy if that's the case!
'72 95 (The Flying Banana),'72 96 (Bridget),'74 95 (Veronica) | |
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rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 11 May 2012 : 16:41:46
| If it is the autochoke water feed, can I disable it? and how.
It has a new air filter, but if the float is too high, how do I know & how do I adjust it?
Does anyone have a diagram of a twin choke Solex, so I know what I am looking at?
Thanks again all. | |
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john-saab
Administrator
United Kingdom
2682 Posts | Posted - 11 May 2012 : 21:30:25
| What model of Solex?
'72 95 (The Flying Banana),'72 96 (Bridget),'74 95 (Veronica) |
Edited by - john-saab on 11 May 2012 21:31:43 | |
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rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 12 May 2012 : 22:35:31
| I think it's a 32 tdid I do have a photocopy from the previous owner, but it,s poor & in German.
I think I know why it's running poorly, The volume control screw is screwed right in, which I assume means it's not getting much air. The carb was set up by the garage when I asked them to tune it!
What I need to know now is how to tune it from scratch and how come it's gradually got worse?
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transit80
V4 Mad
United Kingdom
775 Posts | |
rhampsheir
V4 Fanatic
United Kingdom
236 Posts | Posted - 18 May 2012 : 12:26:56
| | Thanks for that Chris, what I also need is some info on the actual carb model. Does anyone know what other cars used a Solex 32/32 TDID. It's not covered in the Saab 96 Haynes manual. I was thinking if I could pick up another cheap manual I could use it just for the carb. | |
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transit80
V4 Mad
United Kingdom
775 Posts | |
| Topic | |
very poor fuel consumption
