Fresh rebuild won't start
Fresh rebuild won't start
Question for all of you smarter guys than me ( which is everyone). I recently rebuilt my engine, timed according to everyone's posts, got it to fire for about 30 sec last night, couldn't get it started again after. Any ideas?
I tried moving the timing a tooth back and forward which seemed to make it worse (sounding). I've seen were some say rotaries are notorious for having low compression after a fresh rebuild until everything seats.
Let me know your thoughts
I tried moving the timing a tooth back and forward which seemed to make it worse (sounding). I've seen were some say rotaries are notorious for having low compression after a fresh rebuild until everything seats.
Let me know your thoughts
You could place oil in the housings via the spark plug holes (a tablespoon should do) to help build compression. And did the engine die after 30 seconds or did you turn the engine off? If you turned it off then you should try letting the engine run longer.
It just died. I tried to keep it going but, it didn't stay running.
Last edited by Coinshark; Apr 19, 2016 at 08:20 AM.
before changing your timing and risk detonation or something serious I would just check the simply stuff first (triple check ground connections, main fuses, main vacuum lines, fuel pressure and fuel cleanliness, spark, compression, deflood) You can check all that in less than an hour without tearing off UIM and stuff. All this will eliminate most your questioning.
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Yeah wait, i didnt notice you said youre moving teeth. you need to set your base timing first. Turn it over and check with a timing light and get ur marks close.
I'll pull my plugs tonight and check them, perhaps they are dirty or something.
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You should just start over.
Do this:
Startup
Ensure the throttle reads smoothly from 0-100% in its full
range of movement.
Power up the fuel pumps and check entire fuel system for leaks before attempting
to start the engine.
Once verified that all sensors are correctly operating and fuel system is functional,
attempt to start the engine. If engine does not start check:
1. Ignition Timing
2. Correct Fuel Pressure
3. Spark Plugs are not fouled or wet
4. Engine Compression
5. Ignition is wired in correct firing order
6. Ignition is firing on intake stroke not exhaust stroke
Once engine is running, ensure fuel pressure remains correct under all conditions and
that battery is charging.
Do this:
Startup
Ensure the throttle reads smoothly from 0-100% in its full
range of movement.
Power up the fuel pumps and check entire fuel system for leaks before attempting
to start the engine.
Once verified that all sensors are correctly operating and fuel system is functional,
attempt to start the engine. If engine does not start check:
1. Ignition Timing
2. Correct Fuel Pressure
3. Spark Plugs are not fouled or wet
4. Engine Compression
5. Ignition is wired in correct firing order
6. Ignition is firing on intake stroke not exhaust stroke
Once engine is running, ensure fuel pressure remains correct under all conditions and
that battery is charging.
You should just start over.
Do this:
Startup
Ensure the throttle reads smoothly from 0-100% in its full
range of movement.
Power up the fuel pumps and check entire fuel system for leaks before attempting
to start the engine.
Once verified that all sensors are correctly operating and fuel system is functional,
attempt to start the engine. If engine does not start check:
1. Ignition Timing
2. Correct Fuel Pressure
3. Spark Plugs are not fouled or wet
4. Engine Compression
5. Ignition is wired in correct firing order
6. Ignition is firing on intake stroke not exhaust stroke
Once engine is running, ensure fuel pressure remains correct under all conditions and
that battery is charging.
Do this:
Startup
Ensure the throttle reads smoothly from 0-100% in its full
range of movement.
Power up the fuel pumps and check entire fuel system for leaks before attempting
to start the engine.
Once verified that all sensors are correctly operating and fuel system is functional,
attempt to start the engine. If engine does not start check:
1. Ignition Timing
2. Correct Fuel Pressure
3. Spark Plugs are not fouled or wet
4. Engine Compression
5. Ignition is wired in correct firing order
6. Ignition is firing on intake stroke not exhaust stroke
Once engine is running, ensure fuel pressure remains correct under all conditions and
that battery is charging.
So, I think after over 6 months of being down for the rebuild the gasoline in my tank went bad. I checked timing, fuel pressure, plugs, ignition wiring. I ran out of time last night to do my compression test though.
Last edited by Coinshark; Apr 22, 2016 at 12:00 PM.
Joined: Jul 2013
Posts: 2,596
Likes: 799
From: █▬█ █▄█ █▬█ █▄██▬█ █▄█ █▬█ █▄█
I checked timing, fuel pressure, plugs, ignition wiring. I ran out of time last night to do my compression test though.
Joined: Aug 2002
Posts: 2,614
Likes: 31
From: Freeland, MI
Fresh rebuilds can be a biatch to get running, deflood it again, pull the plugs and put oil in the chambers, hook up a battery charger with a boost start option and try it, if that doesn't do it, pull start it
Joined: Feb 2001
Posts: 29,798
Likes: 128
From: London, Ontario, Canada
Stop farting around with timing. It has little effect on startup as long as the CAS is on the right tooth.
By this time the engine is very flooded.
Push start it with another vehicle. Don't waste further time and frustration. Get it up to about 20 MPH then carefully let the clutch out in 1st gear. As long as the engine is capable of running (ie. fuel, spark), it will run.
Hold the RPMs up around 2500 to burn off all the crap.
By this time the engine is very flooded.
Push start it with another vehicle. Don't waste further time and frustration. Get it up to about 20 MPH then carefully let the clutch out in 1st gear. As long as the engine is capable of running (ie. fuel, spark), it will run.
Hold the RPMs up around 2500 to burn off all the crap.
Joined: Aug 2002
Posts: 2,614
Likes: 31
From: Freeland, MI
Its not that the starter is to weak, its that the starter can only spin up to so many RPMs, and you have alot of things going against you
One being its a fresh rebuild, compression is going to be pathetically low until you get it running and give the seal time to seat
Two being its flooded, when an engine is flooded, it lowers the compression even more, so now you have even LOWER compression
The thing with pull/push starting it is when you release the clutch, the movement of the car will spin the engine over faster than the starter ever can, which the faster a engine spins, the more compression it will build (to a point)
Before you push/pull start it, do as i said and put some oil in the plug holes, it will help bring the compression up to fire it
One being its a fresh rebuild, compression is going to be pathetically low until you get it running and give the seal time to seat
Two being its flooded, when an engine is flooded, it lowers the compression even more, so now you have even LOWER compression
The thing with pull/push starting it is when you release the clutch, the movement of the car will spin the engine over faster than the starter ever can, which the faster a engine spins, the more compression it will build (to a point)
Before you push/pull start it, do as i said and put some oil in the plug holes, it will help bring the compression up to fire it
Stop farting around with timing. It has little effect on startup as long as the CAS is on the right tooth.
By this time the engine is very flooded.
Push start it with another vehicle. Don't waste further time and frustration. Get it up to about 20 MPH then carefully let the clutch out in 1st gear. As long as the engine is capable of running (ie. fuel, spark), it will run.
Hold the RPMs up around 2500 to burn off all the crap.
By this time the engine is very flooded.
Push start it with another vehicle. Don't waste further time and frustration. Get it up to about 20 MPH then carefully let the clutch out in 1st gear. As long as the engine is capable of running (ie. fuel, spark), it will run.
Hold the RPMs up around 2500 to burn off all the crap.
Thanks for all the suggestions everyone! Sorry for being a rotary nub
Last edited by Coinshark; Apr 25, 2016 at 10:09 AM.






I has a compression tester already. We just ran out of time.