New Engine Does Not Start ?
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Rotary Freak
Joined: Dec 2001
Posts: 2,941
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From: sandiego, ca
New Engine Does Not Start ?
Ok heres what I know...When I try and start it using a jumper V6 car (big battery) I get nothing but a dry cranking sound and thud thud thud from the exaust. It sounds like it catches once in a wile but doesent start.
So I listen under the hood wile cranking...I hear LOUD *** shhht shhht sounds from the intake which is normal but I also hear the maf sensor going clink back and forth. I think this is normal to. I dont know whats up. Im sure the spark is fine and its getting fuel...
What if I spray some carb cleaner through the intake wile cranking ?
So I listen under the hood wile cranking...I hear LOUD *** shhht shhht sounds from the intake which is normal but I also hear the maf sensor going clink back and forth. I think this is normal to. I dont know whats up. Im sure the spark is fine and its getting fuel...
What if I spray some carb cleaner through the intake wile cranking ?
I wouldnt spray carb cleaner. I would consider either:
A: Putting some oil into the chambers to boost compression
B: Checking your connections
C: Priming the fuel system by jumpering the fuel pump jumper (yellow connector on the right side of the engine bay).
Its like starting a flooded motor.
Jarrett
A: Putting some oil into the chambers to boost compression
B: Checking your connections
C: Priming the fuel system by jumpering the fuel pump jumper (yellow connector on the right side of the engine bay).
Its like starting a flooded motor.
Jarrett
Joined: Dec 2001
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From: NY, MA, MI, OR, TX, and now LA or AZ!
If that doesn't work, get someone to hold the AFM open slightly and slowly push it in as you're cranking, good way to find out if you have vac leaks, as it makes up for the unmetered air.
Thread Starter
Rotary Freak
Joined: Dec 2001
Posts: 2,941
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From: sandiego, ca
Oh so that just makes the pump work even when the ignition isnt energized so it can build pressure ?
If its to cut fuel then thiers other ways like pulling the EGI fuse but I did that.
If its to cut fuel then thiers other ways like pulling the EGI fuse but I did that.
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Well, we're both on the 'vote poll', so I guess you can say we sort of are right about now, but *shrug* it's more a parody of a presidential campaign!
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From: usa
From my webpage:
Once a fresh rebuild is assembled and installed there are a couple of things to do before trying to make it run. Fresh rebuilds are often low compression, and as a result never run very well initially, sometimes poorer than the old one they replaced. Remember that every minute the rebuild runs it is getting stronger, and how you treat it now is how it will run for you later.Here is an outline, as well as breakin recommendations. These can apply to any rebuild, professional or self-built. IT is also recommended to have a fuel cutoff switch installed(for 86-88s) before trying to start a rebuild, as it will want to flood every time it is shut off. Note that 89-91 models have built-in anti-flood features, just depress the throttle fully to deprive the engine of fuel and unflood it.
1) remove EGI fuses underhood to disable fuel/spark.
2) crank for 10 seconds at a time, once per minute, at least 3 times, to prime the oil system and build oil pressure before startup. You can usually see 20-30psi of oil pressure during cranking.
3) Inject some oil into the lower plug holes of each chamber to help build compression for startup. Fresh rebuilds with old housings are very low compression initially. My rebuilds already have some assembly oil injected.
4) Make preparations to idle the engine up before startup. A rebuild will not even consider idling normally for the first few hours. Use the hard idle set screw(on throttle body by linkages, 8mm locknut with flathead setscrew inside, covered by factory jb weld) to adjust the throttle somewhat open at idle, a few turns are necessary. You want the rebuild to idle at around 1500rpm for the first day or more. IF you don’t do this ahead of time, and you’re by yourself, youll be stuck inside the car holding the gas instead of outside checking for leaks and such, and if you stop the engine it’ll be hard to get started again.
5) A battery charger or external jump(another car) is sometimes helpful in starting a rebuild, as old or partially discharged batteries sometimes lack the strength to really kick over an engine and build enough compression to start. A strong charge is a must here.
6) Be prepared for smoke…there is assembly lube in the engine, which will be burned out in the form of smoke. Expect this to get into your exhaust and smoke can remain for up to 8 hours afterwards until it is all burned out slowly.
7) Be prepared to watch for leaks…oil lines, coolant hoses, gaskets, and other connections should be examined for leaks. Youll also want to keep an eye on the gauges…oil pressure, water temperature, voltage, etc.
8) Once it is running and youre satisfied everything is stable, set the idle to around 1500rpm and let it be. Since compression is constantly changing, there isn’t much use in adjusting and readjusting idle and TPS settings until breakin is almost complete, as the settings will change almost daily. Right now, the more you can drive it, the better. IT is very helpful for the first few days even to just let it idle in the driveway all day.
9) Breakin should be completed as follows: keep rpms under 4000, oil changes at 500 and 2000 miles, and no boost above atmospheric(turbo models).
10) Great improvements in starting, idle quality and overall smoothness/power will begin occurring immediately, but most improvement will be reached by 1500 miles, at which time you can gradually increase rpm and boost. By the time the engine reaches 2000 miles, it is basically broken in and can be treated as you wish within reason.
11) Don’t be disappointed if it doesn’t start immediately. It is very easy to leave off an important connector or get fuel lines backwards, etc. Just keep checking things. Adding more oil/atf to the chambers often helps build compression and start the engine. Also old plugs, or plugs that have sat in a flooded engine for any time at all will cause an engine to run poorly or not at all. I find that plugs foul several times the first day of running, and 2-4 times during subsequent breakin. It is recommended to have several sets of (used) plugs on hand, along with a wirebrush to clean them off with once theyre fouled.
Once a fresh rebuild is assembled and installed there are a couple of things to do before trying to make it run. Fresh rebuilds are often low compression, and as a result never run very well initially, sometimes poorer than the old one they replaced. Remember that every minute the rebuild runs it is getting stronger, and how you treat it now is how it will run for you later.Here is an outline, as well as breakin recommendations. These can apply to any rebuild, professional or self-built. IT is also recommended to have a fuel cutoff switch installed(for 86-88s) before trying to start a rebuild, as it will want to flood every time it is shut off. Note that 89-91 models have built-in anti-flood features, just depress the throttle fully to deprive the engine of fuel and unflood it.
1) remove EGI fuses underhood to disable fuel/spark.
2) crank for 10 seconds at a time, once per minute, at least 3 times, to prime the oil system and build oil pressure before startup. You can usually see 20-30psi of oil pressure during cranking.
3) Inject some oil into the lower plug holes of each chamber to help build compression for startup. Fresh rebuilds with old housings are very low compression initially. My rebuilds already have some assembly oil injected.
4) Make preparations to idle the engine up before startup. A rebuild will not even consider idling normally for the first few hours. Use the hard idle set screw(on throttle body by linkages, 8mm locknut with flathead setscrew inside, covered by factory jb weld) to adjust the throttle somewhat open at idle, a few turns are necessary. You want the rebuild to idle at around 1500rpm for the first day or more. IF you don’t do this ahead of time, and you’re by yourself, youll be stuck inside the car holding the gas instead of outside checking for leaks and such, and if you stop the engine it’ll be hard to get started again.
5) A battery charger or external jump(another car) is sometimes helpful in starting a rebuild, as old or partially discharged batteries sometimes lack the strength to really kick over an engine and build enough compression to start. A strong charge is a must here.
6) Be prepared for smoke…there is assembly lube in the engine, which will be burned out in the form of smoke. Expect this to get into your exhaust and smoke can remain for up to 8 hours afterwards until it is all burned out slowly.
7) Be prepared to watch for leaks…oil lines, coolant hoses, gaskets, and other connections should be examined for leaks. Youll also want to keep an eye on the gauges…oil pressure, water temperature, voltage, etc.
8) Once it is running and youre satisfied everything is stable, set the idle to around 1500rpm and let it be. Since compression is constantly changing, there isn’t much use in adjusting and readjusting idle and TPS settings until breakin is almost complete, as the settings will change almost daily. Right now, the more you can drive it, the better. IT is very helpful for the first few days even to just let it idle in the driveway all day.
9) Breakin should be completed as follows: keep rpms under 4000, oil changes at 500 and 2000 miles, and no boost above atmospheric(turbo models).
10) Great improvements in starting, idle quality and overall smoothness/power will begin occurring immediately, but most improvement will be reached by 1500 miles, at which time you can gradually increase rpm and boost. By the time the engine reaches 2000 miles, it is basically broken in and can be treated as you wish within reason.
11) Don’t be disappointed if it doesn’t start immediately. It is very easy to leave off an important connector or get fuel lines backwards, etc. Just keep checking things. Adding more oil/atf to the chambers often helps build compression and start the engine. Also old plugs, or plugs that have sat in a flooded engine for any time at all will cause an engine to run poorly or not at all. I find that plugs foul several times the first day of running, and 2-4 times during subsequent breakin. It is recommended to have several sets of (used) plugs on hand, along with a wirebrush to clean them off with once theyre fouled.
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