1985 (Ee80) Sprint Carb Tuning

[guyrat]

Hi,

I have a 1985 Toyota sprinter which used to do well on fuel.

There was an oil leak and the engine was recently overhauled.

now the car does a little over 8 KM per litre. It used to do over 10 per liter in town with AC.

Anyone knows how this can be fixed?

Last week, the Carb was cleaned with cleaner. the rings have been replaced with the spark plugs, plug harness etc.

There does not seem to be a performance loss but there is a loss of mileage which is very expensive.

Any hints to fix this? I was told this carburettor is complicated to tune so maybe the garage accidentally changed something that should not be changed.

Thanks!

Gayan

Edited July 16, 2013 by guyrat

[NZer]

Give it to a good Carb bass. Im not an expert on Carbs so not sure who you should consult but someone here will be helpful. Use a good carb repair kit which has all the jets and stuff and overhaul the carb. this might fix the issue. keep us posted.

[Jaliya48]

The carb cleaners on their own aren't that great, to be honest. Your best bet is to get a mechanic to remove the carb from the manifold and clean it thoroughly, then spray the carb cleaner and get a good engine tuneup done to top it all off.

[Rumesh88]

  On 7/16/2013 at 11:11 AM, guyrat said:

Hi,

I have a 1985 Toyota sprinter which used to do well on fuel.

There was an oil leak and the engine was recently overhauled.

now the car does a little over 8 KM per litre. It used to do over 10 per liter in town with AC.

Anyone knows how this can be fixed?

Last week, the Carb was cleaned with cleaner. the rings have been replaced with the spark plugs, plug harness etc.

There does not seem to be a performance loss but there is a loss of mileage which is very expensive.

Any hints to fix this? I was told this carburettor is complicated to tune so maybe the garage accidentally changed something that should not be changed.

Thanks!

Gayan

Well Gayan, it is unfortunate that you did not get the expected performance after an overhaul. It is not the carb itself that is complicated in this model but the associated vacuum pipes and solenoid valves. If your carb has not been unnecessarily meddled with previously, then the tuning it simply boils down to maintaining the correct fuel level, idle speed (with and without AC), and idle mixture adjustments. (Secondary carb is not that important at this stage). But before all this you need to ensure that all the vacuum pipes running from the inlet manifold (both before and after the throttle) are intact. Also get your ignition timing checked at the same time. Also if the car had been idling for sometime pending the overhaul there is a chance of carb gaskets drying up resulting in fuel or air leaks. If that is the case you need to rebuild the carb with a repair kit.