Engine problems...help please!

[LetsRolla]

Mga sir good day po, help naman po sa problem ng oto ko, 1990 Toyota Corolla 16v (4af engine).

Last week po kasi na sira yung float sa carb so namamatay sya pag binitawan yung gas pedal, ok na sya ngayon pero pag cold yung engine, at 1k-1.5k rpm nag hehesitate yung engine, may puting usok sa muffler tapos ang bagal ng hatak pero pag uminit na, ok na sya. Tried adjustments, changing the filter, etc.

Additional question: saan po ok magpagawa ng shims for valve tappets?, yung mura lang po yung singil at ano pong parts na kailangan palitan?

Salamat po :D

[afrasay]

pag cold ang engine, like bagong start lang, mataas talaga ang rpm for it to attain the operating temperature at the least possible time. pag malamig talaga ang makina mahina ang hatak compared sa warm-up car. at mausok din. yun shims sa auto supply mayrun or sa may machine shop kung saan pagawa ito. halos parepreho lang price nila (machine shop) puwera nalang kung sa malalaking shop ka pagawa.

[LetsRolla]

Pero the hesitation, sobrang lakas, parang namamatayan nga ng engine eh. thats only * 1.5k to 2k rpm pero beyond that ok na, white yung smoke pero we inspected the oil inside the engine, ok naman and the water in the rad thers no oil, I never expereinced this before eh.

[afrasay]

ah so dati hindi siya ganyan...well pa adjust mo valves (kung di self adjusting) and have it tune up.

[LetsRolla]

Yeah, tune up lang kaya ang solusyon or there's a problem with my carb?

[mangdencio]

Mga sir good day po, help naman po sa problem ng oto ko, 1990 Toyota Corolla 16v (4af engine).

Last week po kasi na sira yung float sa carb so namamatay sya pag binitawan yung gas pedal, ok na sya ngayon pero pag cold yung engine, at 1k-1.5k rpm nag hehesitate yung engine, may puting usok sa muffler tapos ang bagal ng hatak pero pag uminit na, ok na sya. Tried adjustments, changing the filter, etc.

Additional question: saan po ok magpagawa ng shims for valve tappets?, yung mura lang po yung singil at ano pong parts na kailangan palitan?

Salamat po :D

hi lets rolla! white smoke (as you've said) is characteristic of starting a cold engine (due to low engine temperature) and does not necessarily require any repair. a bluish white smoke is a sign of oil burning.
instead, go back to your serviced carburetor to find out if the problem lies there. check the choke plate if it closes, jet valves if they're clogged, and the float again. try fiddling with the idle mixture and speed screws if it helps.
your local machine shop should have shims ready for your valve service if it will ever require one. i don't think it needs one, unless you hear some tapping sound in the engine. hope this helps.

[LetsRolla]

Hello mga sir!, well im hearing tapping sounds already eh. I'll try to change the plugs and fuel filter muna, hope this works.thanks :D

[LetsRolla]

Tried changing the plugs, still no effect...

[mangdencio]

Hello mga sir!, well im hearing tapping sounds already eh. I'll try to change the plugs and fuel filter muna, hope this works.thanks :D

test each spark plug first before replacing them. with the engine idling, pull the corresponding high tension wire (the red cables connecting the spark plug to the distributor and note if there's a change in engine sound (noise)i.e. the engine should "roughen" to indicate a good spark plug..if there's no change, the spark plug might be at fault...remove that spark plug and check for pattern of wear (carbon fouled, oil fouled, etc)...the affected cylinder needs to be tested for loose compression...wet and dry methods...
going back to the tapping sounds, an experienced ear will be able to differentiate a valve problem that will necessitate valve clearance adjustments, valve seat / valve lapping from a 'katok'of a piston slap.
to recap, i think you'll save more by determining the cause of the noise rather than replacing parts that you think might solve the problem...pls. update

[LetsRolla]

test each spark plug first before replacing them. with the engine idling, pull the corresponding high tension wire (the red cables connecting the spark plug to the distributor and note if there's a change in engine sound (noise)i.e. the engine should "roughen" to indicate a good spark plug..if there's no change, the spark plug might be at fault...remove that spark plug and check for pattern of wear (carbon fouled, oil fouled, etc)...the affected cylinder needs to be tested for loose compression...wet and dry methods...
going back to the tapping sounds, an experienced ear will be able to differentiate a valve problem that will necessitate valve clearance adjustments, valve seat / valve lapping from a 'katok'of a piston slap.
to recap, i think you'll save more by determining the cause of the noise rather than replacing parts that you think might solve the problem...pls. update

Hello, well I tried cleaning then pulling the spark plugs one by one and the engine ran rough, so it should be ok. I did notice that whenever I turn off the engine for a long time, lets say overnight, it significantly has problems running and it hesitated at 1.5k to 2k rpm, but after the engine warmed up already, its already running fine, thats why its so hard to determine the problem because you need to inspect the problem after the engine has cooled enough. Some say its the carb, some say its the idle and f/a mixture and I really have no idea whats going on. Thanks :D

[mangdencio]

Hello, well I tried cleaning then pulling the spark plugs one by one and the engine ran rough, so it should be ok. I did notice that whenever I turn off the engine for a long time, lets say overnight, it significantly has problems running and it hesitated at 1.5k to 2k rpm, but after the engine warmed up already, its already running fine, thats why its so hard to determine the problem because you need to inspect the problem after the engine has cooled enough. Some say its the carb, some say its the idle and f/a mixture and I really have no idea whats going on. Thanks :D

good morning lets rolla!

your engine should be ok at around 600rpm on idle (via tachometer). the power system of the carb might be at fault then. this system is responsible for feeding the engine with ample air/fuel mixture at 2k rpm and above by opening a secondary barrel...the idle system of the carb can only handle up to about 1k rpm until it recruits the power system to attain a smoother running engine..(when you rev up to increase ground speed for example)

unless you have a leaking carburetor...gaskets, hoses...and other issues (like ignition timing!) your engine should be fine under normal operating conditions except for the tapping sounds you hear which i suspect is in the engine itself (valves, springs, etc)..
have it checked by an experienced mechanic so the problem is corrected at the soonest possible time to avoid further damage. it's kinda hard to pinpoint the problem without actually inspecting the engine.hope this helps a bit...