crying here... not a good phone call
05-27-2012, 01:27 PM
#107
Race Car
Good move Hawk....
I am doing an engine rebuild in the coming months, I will be happy to share any findings/info/tips etc as I go along.
Good Luck
I am doing an engine rebuild in the coming months, I will be happy to share any findings/info/tips etc as I go along.
Good Luck
05-27-2012, 02:00 PM
#108
Race Car
Thread Starter
I'd put good money on this being your problem. I've had several die sitting for extended periods. The little pump section on them is amazingly small for the volume they put out, it doesn't take much to kill them or gum them up.
Also there is a big flaw in the mech's thinking, if the motor doesn't run and you go through all the trouble of a top end you're still going to have to find out the reason for it not running.
The only potential mechanical failure I could see as a result of sitting is the remote possibility that a chain tensioner bled down and upon starting jumped a tooth when you went to start it. That would be easy to check the cam timing to confirm.
And you're sure your son didn't accidentally stuff it in second being unfamiliar/nervous about driving it?
Also there is a big flaw in the mech's thinking, if the motor doesn't run and you go through all the trouble of a top end you're still going to have to find out the reason for it not running.
The only potential mechanical failure I could see as a result of sitting is the remote possibility that a chain tensioner bled down and upon starting jumped a tooth when you went to start it. That would be easy to check the cam timing to confirm.
And you're sure your son didn't accidentally stuff it in second being unfamiliar/nervous about driving it?
05-27-2012, 03:15 PM
#109
Rennlist Member
Well if it's got even a mediocre compression, the timing is ok and gas then on to ignition as others have mentioned, I know it sounds condescending and you may have mentioned it before, but the car has plenty of gas and the fuel pump relay is ok?
05-27-2012, 08:37 PM
#115
Rennlist Member
Join Date: Jun 2010
Location: Detroit (Rock City); 1990 C4
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Hawk, keep your head.
1. Starting fluid is way more flammable than gas; that's why it's used. I believe it's possible to have spark sufficient to run the car on ether (starting fluid) but maybe not fuel. I don't think you can rule out spark at this point.
2. With respect to fuel, a new pump and flow at the rail doesn't completely address the actual delivery of fuel to the engine. When you're cranking but not starting, does the exhaust smell of raw gas? So far as I can tell you've no idea if the injectors are actually firing.
1. Starting fluid is way more flammable than gas; that's why it's used. I believe it's possible to have spark sufficient to run the car on ether (starting fluid) but maybe not fuel. I don't think you can rule out spark at this point.
2. With respect to fuel, a new pump and flow at the rail doesn't completely address the actual delivery of fuel to the engine. When you're cranking but not starting, does the exhaust smell of raw gas? So far as I can tell you've no idea if the injectors are actually firing.
05-27-2012, 09:43 PM
#116
Nordschleife Master
A strong blue spark is needed at full rpm / hp .
So you are thinking it has a spark that will jump the gap , ignite the starter fluid and not ignite gasoline ? A magic spark ?
05-27-2012, 10:16 PM
#117
Burning Brakes
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Higher voltage is required to spark under compression much less @ atmospheric pressure. A yellow spark is a tell tale sign of a weak spark, if in doubt a spark tester is a handy tool.
05-28-2012, 10:29 AM
#119
Race Car
Thread Starter
I can smell gas at the exhaust when trying to start. Now I could have 2 sets of bad coils, but I swapped my coils a few yrs ago as a preventative thing, but kept the old ones. I've swapped the old coils out, and had the same results with both.
05-28-2012, 10:32 AM
#120
Burning Brakes
Measure the voltage on the low-tension posts on the coil....are they getting a full 12+V?
I've had a similar experience to what Feral's alluding to. The starter spray is very effective and got the motor to fire up briefly, but in reality it had a wiring issue to the coils, which meant that they would never have enough juice to run by itself without starter spray (and I also initially concluded that if it fired up on starter spray, then it had good spark, which was wrong)...worth a try?
I've had a similar experience to what Feral's alluding to. The starter spray is very effective and got the motor to fire up briefly, but in reality it had a wiring issue to the coils, which meant that they would never have enough juice to run by itself without starter spray (and I also initially concluded that if it fired up on starter spray, then it had good spark, which was wrong)...worth a try?