Maruti 800 [ Certain Queries ]

[Sankar]

For idle rpm adjustment you don't have to fiddle with these two screws. Idle rpm is adjusted using the throttle stop screw on the right hand side of the carb.

[sumeethaldankar]

Originally Posted by Sankar

For idle rpm adjustment you don't have to fiddle with these two screws. Idle rpm is adjusted using the throttle stop screw on the right hand side of the carb.

Hi
can you tell me where it is located.

thanks

[archat68]

Originally Posted by DHABHAR.BEHRAM

Dear Mr.J.Ramprakash - hello to you. I am giving complete details of work that you "may decide" to do on the Maruti 800 as regards engine tune-up> If you do, you will get exemplary performance.

Carburettor:
Remove the air cleaner and carburettor from the engine. Open the carburettor (including the venturies), immerse it in new brake fluid and leave it for 24 hours. Then clean it with further new brake fluid, then with petrol and then use a good quality carburettor cleaning spray to clean out gum from each and every miniscule aperture. Assemble with new gaskets between the main body and the bottom cover, main body and the top cover (the size M5*0.8 screws come with the top gasket, use them) and between the throttle body and the intake manifold. Use Maruti Zen's venturies and a Maruti Van idler jet in the primary circuit. It has 8 bleeder holes as compared to the Maruti 800's 4, so you will get better control of progression from the idling circuit to the main circuit. I have used these systems for more than 10 years in all my Maruti 800s and they all run beautifully. Fuel consumption is not affected.

Positive Crankcase Ventilation (PCV) valve:
Remove the rubber hose and spray some carburettor cleaning fluid in this valve. This way, any gum stuck in this area will get cleaned and you will realise good PCV performance, which corelates directly to idling quality.

Air cleaner element:
Just remove the old element and throw it out. Use a new Purolator element only. Clean the air cleaner container from inside.

Spark plugs:
Use only NGK BP5ES spark plugs. Plug gap must necessarily be 0.9 mm (36 thou) only.

Distributor:
If you have a PMP make distributor, remove it and throw it out. It does not provide spark advance as it should. If you have Lucas TVS or Nippondenso (mostly it will be Lucas TVS), connect a good dwell meter and check for runout of the distributor shaft. If the shaft runs out, dwell will vary. If variance is more than 1 degree, timing and performance will not be realised. Remove the distributor and replace it with a new one having confirmed shaft runout within specifications. The dwell angle must be set to 52 degrees and the static ignition timing must be set to 7 degrees BTDC (before top dead centre) with vacuum advance connected in the circuit.

Vacuum hoses:
Replace if frayed, hardened, cracked or in any way loose or out of place.

Fuel filter:
Remove the old fuel filter and throw it out. Use a new Purolator make fuel filter.

Originally Posted by DHABHAR.BEHRAM

My reply got posted by some error. I have not finished. I am continuing.

Fuel filter:
Remove the fuel filter and throw it out. Use a new Purolator make fuel filter.

Valve clearence setting (tappet setting):
Use a 0.15 mm (6 thou or 0.006 inches) feeler guage for the 3 inlet valves and 0.175 mm (7 thou or 0.007 inches) feeler guage for the 3 exhaust valves. This must be done in engine in absolute dead cold condition (standing overnight without starting). As this is a 3 cylinder engine, you have to ensure that the concerned piston is at the start of the firing stroke at TDC. Use a checklamp connected to the low tension circuit side of the distributor to define individual TDC.

Engine idling rpm:
780+/-20 without AC, adjust from volume control and throttle control screws, 1100+/-50 with FICD operating, adjust FICD screw.

Intake manifold vacuum:
480 mm of Hg minumum in idling with all circuits connected without AC.

Camshaft drive belt:
Generally nothing happens but if you experience power drop at @ 50000 kms, just tighten this belt.

Results after action:
Spark plug insulators light pink in colour
Exhaust pipe end cleah in general use and greyish pinkish colour immediately after a long fast drive.

Best regards,

Behram Dhabhar

Hi Behramji,
Shall I follow these points for a Carb Zen tuning and carb overhaul?

[star_aqua]

Originally Posted by sumeethaldankar

Hi
can you tell me where it is located.

thanks

Just follow the accelerator cable and it will end up with the carburetor. ask someone to press the accelerator and observe below at the carburetor below the airfilter. now you will observe a moving cable which pulls the throttle lever and the same is held by a stopper with screw adjustment. just change the screw position and thats it. you found it.

[techn0l0gist]

check this linky A PURRFECT M800 - DOES IT EXIST?!

[Sankar]

Originally Posted by sumeethaldankar

Hi
can you tell me where it is located.

thanks

Originally Posted by star_aqua

Just follow the accelerator cable and it will end up with the carburetor. ask someone to press the accelerator and observe below at the carburetor below the airfilter. now you will observe a moving cable which pulls the throttle lever and the same is held by a stopper with screw adjustment. just change the screw position and thats it. you found it.

Yep, follow the instructions by star_aqua and you'll find it

When you face the car from the front the throttle cable and throttle links would be to your left under the air filter assembly.

[pras71]

Hello friends!
i own a 10 year old carburettor type maruti 800 that has done over 140,000 kms. mileage is still excellent. and its on LPG for the past 8 years. with over 120,000 on LPG. gives around 370 to 400 kms per 14 kg of LPG.
just last year, i had to struggle a lot for low mileage on LPG. used to give 280 to 300kms only (per 14kg). after lots of struggle and good advice from Team BHP post regarding the advance retard timing setting to 52 degrees dwell angle sharp, and changing the advance to nearly 9 degrees, mileage increased tremendously ! so to share my experience and make better use of fuel, i am typing out this mail.
Check dwell angle correctly ! usually the mechanic does it by guess work ! should be 0.4mm seperation between contacts exactly to give 52 degrees dwell . but when checked for actuals before changing, it was around 40 degrees only ! setting at home is very tedious. keeps slipping between extreme positions. the sparks on contact and seperation are the only guides ! and a simple compass protactor was used to read the angles. crude method. luckily worked. but took over 2 hours for an otherwise 15 minutes job with proper instruments !
distributor angle is recommended to be 7 degrees . one local mechanic suggested higher advance. survey over the net also revealed that LPG requires higher advance timimgs. hence set to around 9 degrees. now absolutely fantastic mileage ! long distance gives over 410kms per 14 kg !!
also Nulon engine additive was used. just 100 ml 9as for 2 wheelers) instead of 500 ml as recommended by company. but this too yielded smooth results.gad kit is Star-gas. another fact noticed was that the idling knob of the gas kit should be turned from poor fuel (alomost tight) to loosening till just enough fuel for idling.. from dying engine to just enough rpm. further turning also results in increased rpm and again later lower rpm at still higher rotations. so movement of idling knob should be from highest rpm to tightening to give just enough idling speed. opening up the gas kit will reveal the mechanism of idling knob.
good lucks to all car fiddlers like myself.
prasanna

[sharma_sanjeevi]

@star_aqua & gpa, thanks for your valuable inputs guys, sorry for replying late, as i was not in town.

[CrackedHead]

Originally Posted by DHABHAR.BEHRAM

If you have Lucas TVS or Nippondenso (mostly it will be Lucas TVS), connect a good dwell meter and check for runout of the distributor shaft. If the shaft runs out, dwell will vary. If variance is more than 1 degree, timing and performance will not be realised. Remove the distributor and replace it with a new one having confirmed shaft runout within specifications. The dwell angle must be set to 52 degrees and the static ignition timing must be set to 7 degrees BTDC (before top dead centre) with vacuum advance connected in the circuit.

Sorry for reviving such an old thread.

I am confused about the correct dwell angle for the F8B engine. The service manual and the Lucas TVS website Lucas TVS website mention -

Dwell angle : 62° ± 3°

Thats a difference of 10° ! Can you please tell me about the advantages of setting the dwell angle to 52°.

The current dwell meter readings are showing a dwell of 66° at idle (@800 rpm) and 63° at higher RPM's. Does this indicate shaft run out? Can this be rectified by overhauling/machining the distributor (if yes, then where can I get this done)?

Thanks for helping me out.

[qqplus]

I am currently havin an issue about my 800. The issue is of reduced mileage.
I am getting somewhere around 14 even on highways which at some time used to be 21-22.
I drive at moderate speeds. (most of the time constantly at 80 kmph depending on the road condition)

The recent changes in the car that I consider to be the possible causes of the reduction in mileage:
1) Since a couple of months, a strange sports car like sound has developed when I accelerate slightly more in 2nd or 3rd gear. Mechanic told theres some prob with the exhaust.
2) Changed my tires from 145/70/R12 to 155/70/R12. I personally do not believe it should bring my mileage down from around 20 to 14.

Servicing is due for the car which I hope will solve the problem.

I would like to know if anyone of you can probably give some input here.

[dr.faramroze]

If yours is 5 years old car, get a compression test done and get a decarbonisation done if there is piston ring wear, if its a carb model, do not get the carb fiddled, instead get the points gap adjusted if needed replace.

155/70r12 is a nice set for m800. It suffices all performance and comfort parameters.

[sumeethaldankar]

(Mods Using a old thread instead of starting a new one)

Hello,

I have noticed my 800's idle jet always gets clogged and needs cleaning every few months or so. I have noticed this over the period of close 14 years of ownership of the car. I have a k&N installed but the problem was there even before the k&N.

So what could really cause the idle jet to get clogged up. I aways fuel up from half tank to full. Also is it necessary for a carb car to have the accelerator pedal punched a couple of times before starting the car cause i sometimes i do not follow this practice. Could this be the reason the jets get clogged up. I also trust my petrol pump.

thanks