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-   -   Engine won't start -- Please help (http://forums.pelicanparts.com/porsche-911-technical-forum/101893-engine-wont-start-please-help.html)

82SC 03-13-2003 01:41 AM

Engine won't start -- Please help
 
ok...finished the 964 cam install + cleaning, tightening, and going over my engine while it was out...engine was out of service for about 4 months while I did the project every couple weekends

it is back in...cleaned...wires organized, replaced cracked brittle vacuum lines, fixed some oil leaks, took out the whole A/C system, pedal cluster rebuild, fixed crushed oil line, new spark plug wires, new NGK plugs, replaced some pitted rockers...etc...

At first I noticed the battery was dead...doh!!...it is on a trickle charger and I got it to about 75% @ 6amps

Still won't start

ignition
took out #3 plug and tested...nice blue spark
(at first there was no spark but 6 hours on the charge changed that)
checked the rest anyways
CDI terminal 15...OK
rotor and wire resistance...OK (new magnacore BTW my old wires one of them measured 14ohms of resistance)
no oil leak from coil
get voltage pulse when starting motor
check wire to dizzy positions...OK
checked all fuses...OK


fuel
tested the fuel pump by lifting the air sensor plate, lots of noise
I can smell ALOT of fuel in the exhaust
I was afraid I flooded the engine, so I cranked by hand many times, and I tried starting with the fuel pump relay disconnected
I released the pressure in the line into the fuel distributor (no idea why...Bentley manual suggested it)


some clues
found some oil sludge on the bottom of the air sensor plate...cleaned off
I checked my cam timing...found that the 1-2-3 bank is out of range by 0.08mm (but would that make the engine not run at all??)
Will redo timing and valve adjustment via a partial drop (do I have to drain oil?? the car is jacked up pretty high in the rear...I don't want to waste 10qts of oil)
Any better ideas of "un-flooding" the engine? I live in a hilly area, so wheeling around in 5th a la porsche_virus is not an option
I have good oil pressure 3bar
the tach bounces up to 3-4 then to 0 when I drain the battery
my fuel tank is full

Superman 03-13-2003 05:35 AM

An engine needs just three things to run.

1 Compression. It nearly always has this unless it is very old, or recently assembled incorrectly. Be sure your cams are on the correct side, and correct orientation.

2. Proper fuel/air.

3. Right spark at the right time.

Im my experience the problem is usually #3. #2 problems used to be VERY rare. Now they are more common. If you smell gas, then I'd bet you have a #3 problem. Check to see if the spark can jump a half-inch, making a nice snapping sound. Be careful.

robs 03-13-2003 05:54 AM

Some simple ideas...

1) Is the ground strap from the engine/transmission connected to the car?

2) Get a timing flashlight with an inductive clamp and connect it to the
wire of spark plug #1. Pull vacuum line(s) from the distributor. Pull the
fuel relay. Let the starter run and check if you have a stable 5 deg. BTDC
(the right one of the two notches).

3) Pull all six fuel injectors, lift the air flow sensor plate and check
the spray pattern. Let the injectors spray into separate glasses and compare
the flow rate.

4) Check if the plunger of the CIS fuel distributor moves freely: Lift the
sensor plate fully up (fuel pump operates) then release it quickly. Feel if
the plunger hits the lever arm approx. 2 seconds later.

5) If your sensor plate was oily, the fire trap between oil tank vent hose
and intake rubber boot (above fuel distributor / throttle ass'y) may be clogged.
Clean the mesh in this L-shaped aluminum part.

6) Once my SC didn't start, we towed it, put it in 2nd gear, let the motor
turn at 2000 rpm, and with a black cloud it came alive (crude method).

tryan 03-13-2003 06:03 AM

take the battery out of another car. 75% may not be enough. clean the plugs one more time and try it.

Tim L 03-13-2003 07:28 AM

If you have good spark and fuel check and make sure the distributor isn’t 180 degrees out since you changed the cams.

Tim

82SC 03-13-2003 08:04 AM

my strongest suspision is a flooded engine...

or

the cam timing...but like I said the 1-2-3 bank is only 0.08mm off...I would think it would make for a extremely poor running engine, but not one that does not start at all

or

a crapped out battery...will try that (thanks for the suggestion of pulling it out of another car)

well I hope the suggestions roll in...I plan to get back to the car later this afternoon...

thanks again.

MJ

Tim L 03-13-2003 08:33 AM

Not the cam timing. Make sure the distributor rotor is pointing to number one when number one cylinder is at tdc and it’s on its compression stroke.

Tim

Superman 03-13-2003 08:51 AM

Sounds like you know what you're doing. Poor spray pattern can make an engine run poorly, but it would run. I'd second the suggestion to attach a timing light. To see if a spark is really happening inside the engine. When the engine is turning over, the spark may (should) be happening at or just after TDC. Static timing is seldom BTDC, since this can make the engine try to run backwards. If you smell fuel and it won't start, I'm suspicious of the ignition system. If you're concerned about flooding, and if you cleaned the heads near the spark plug holes, then just remove the spark plugs and blast the cylinders with air.

My two greatest suspicions are: ignition, and possibly mechanical mis-assembly (make sure the left cam is on the left, right cam is on the right, etc.).

82SC 03-13-2003 08:52 AM

well I never took the dizzy off the engine and always started timing the cams with the
rotor at the notch
crank at Z1
and cam dot/number facing straight up

so I don't think the timing is reversed 180 but I'll double check when I redo the timing

for those with similar problems using this thread as reference
this thread has some suggestions I may try.

http://forums.pelicanparts.com/porsche-911-technical-forum/101735-back-fire-big-time.html


I'll double check the wiring in the back

also I will clean off the plugs and try to spin some of the fuel out of the cylinders

I will double check the sidedness of the cams...I am 99.9% sure it is right cause I remember using BA's rabbit ear cams trick

82SC 03-14-2003 12:37 AM

[B]UPDATE[B/]

the battery was up to nearly 100% on the charger
well I took out all the plugs and cleaned them, checked gaps...OK (only 1 plug was slightly dirty)
disconnected the coil and fuel pump relay and turned the engine over to try to get out any fuel
sprayed some compressed air to get rid of any fuel

reinstalled everything...nothing

tried the 2 wire connectors in the back of the CIS mentioned in the thread I posted above...engine sounded really bad...and at one point the starter kept going even with the key out...thank god I have a quick disconnect battery terminal

so at this point I am down to

timing of dizzy

cam timing

I highly doubt the dizzy timing cuz I never moved the dizzy during my project
so may be the cam timing...

regardless I am gonna start from step one and check my steps along the way...let me know if you guys think of anything

MJ

Gonna get me one of these to help me...remote starter switches since I don't have a helper

http://www.sears.com/sr/product/details/productdetails.jsp?BV_SessionID=@@@@0324880960.104 7634601@@@@&BV_EngineID=ccheadchkjgfkfgcehgcemgdff mdflk.0&vertical=SEARS&prod_id=00921018000&fromAut o=null&bidsite=null

Clay Perrine 03-14-2003 04:06 AM

Simple way to check the ignition timing. Take out the #1 spark plug. Put a small rag or paper towel over the hole. With the fuel system shut down, bump the starter over until the rag goes flying. Then pull the distributor cap and make sure that the rotor is pointing somewhere near the #1 plug wire.

Another good thing to check is to see if you have compression. Check the engine with a compression tester and see if all 6 holes have compression. If you have the cams mistimed or the valves too tight, you won't have compression,and it won't start.

82SC 03-31-2003 01:19 AM

for those of you following this thread

it ended up being overly tight threads...

http://forums.pelicanparts.com/porsche-911-technical-forum/104469-itzalive-its-alive-its-aliiiiivvee.html

(I always appreciated when someone posted the conclusion to old threads...so I am making it a new habit)


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