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-   -   turn over time (http://www.peachparts.com/shopforum/showthread.php?t=318839)

lsmalley 05-28-2012 02:35 AM

turn over time
 
anyone know how to decrease the turnover time so the car starts right up? I remember a mechanic I used to go to doss something to the car so it fired right up after I told him that ity took too long. any ideas?

strelnik 05-28-2012 08:26 AM

Quote:

Originally Posted by lsmalley (Post 2945058)
anyone know how to decrease the turnover time so the car starts right up? I remember a mechanic I used to go to doss something to the car so it fired right up after I told him that ity took too long. any ideas?

A highly-maintained battery and good grounds, with a good charging system, makes a big difference. So does the proper gearing in the starter.

97 SL320 05-28-2012 08:54 AM

Strong battery, good ignition components, good valve seal all help in quick starts. Not sure what your mech did. On a fuel injected car, if fuel pressure bleeds off / pump is weak long crank times will result.

But, a cranking of say 5 seconds before the engine fires does help engine life as oil pressure has a chance to come up a bit before the engine is running.

My trucks still have carburetors, when cold I crank a bit then push the peddle to set the choke.

lsmalley 05-28-2012 11:42 AM

Battery, plugs, wires, valve seals, rotor, distributor are all less than a year. I guess starter is original, not sure. My car has automatic remote start and so usually I would use that and the car would turn on, but now it will crank, then I would have to do it again. Is that possibly a failing starter? Even if I do use key, I have to crank for about 6 to 8 seconds.

rurlndum 05-28-2012 11:44 AM

For some reason that I'll never understand my cold starts are quicker if I depress and release the accelerator a couple of times before cranking.

duxthe1 05-28-2012 11:46 AM

The fuel pump check valve, fuel accumulator, and fuel injectors are common leak down points. Less commmon is the fuel distributor. When I bought my wagon it had horrendous start times, 15-20 seconds. Turns out somebody dicked with the air horn plate and didn't get it centered. It would hang up before going back to the zero position and attempting to start in less than the zero position would flood the engine.

RichardM98 05-28-2012 12:35 PM

You might want to check out the CPS unless it's fairly new.

lsmalley 05-28-2012 12:44 PM

what is cps?

97 SL320 05-28-2012 01:36 PM

Quote:

Originally Posted by lsmalley (Post 2945190)
. . .valve seals, . . . are all less than a year.

Not valve stem seals, but valve sealing as in where the face of the valve meets the seat. ( AKA valve grind ) Valve stem seals can be changed with the head on and bad ones only cause increased oil consumption not hard starts.

Loss of valve sealing will cause low compression and difficult starting. Have you done a leakdown and compression test?


Quote:

Originally Posted by lsmalley (Post 2945190)
I guess starter is original, not sure.

The starter is a electric motor that spins the engine. They can half fail ( lose one set of field windings, unless it is a perm magnet type ) and crank slowly but the difference is obvious.


Quote:

Originally Posted by lsmalley (Post 2945190)
My car has automatic remote start and so usually I would use that and the car would turn on, but now it will crank, then I would have to do it again. Is that possibly a failing starter? Even if I do use key, I have to crank for about 6 to 8 seconds.

It is sounding like there is a actual problem that can't be diagnosed remotely using limited information.

lsmalley 05-28-2012 01:43 PM

have not done a leakdown or compression test? any special tools needed?

RichardM98 05-28-2012 06:29 PM

CPS = Crankshaft Position Sensor. Early stages of failure can be slow starting. In time will only start when engine is cold not hot.

97 SL320 05-28-2012 06:44 PM

Quote:

Originally Posted by lsmalley (Post 2945267)
have not done a leakdown or compression test? any special tools needed?

Compression test is where you pull the spark plugs, disable the ignition and fuel, install a compression gauge in one spark plug hole, prop the throttle open then crank until the gauge levels off.

This lets you know if there is good valve / ring seal.

A leak down is where you put the piston at the top with both valve closed then pump air in the spark plug hole. Leakdown gauges then tell you the % leakage, I tend just to pump in air and judge good / bad. Air will leak out of :

Oil fill ( common leakage past the piston rings and not always bad )
tail pipe ( if the exhaust valves leak, a slight Hiss is normal on high mile motors )
Throttle (Intake valve leakage, bad as this kills power )
Radiator fill ( bad head gasket / cracked head or very rarely cracked cylinder bore )


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