I now have compression and it still won't run:(
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I now have compression and it still won't run:(
1983 honda aero 50. Completely rebuilt engine.
Well I got the new cylinder. Had it honed and installed it. Compression is noticeably higher. But now it won't start. I got it to sputter a bit, but it won't run continuously.
It has spark, and the bowl is filling up with fuel. What else do I check? I took the carb apart and cleaned it. Everything seemed fine. How do I check to make sure it is actually pumping fuel into the engine? What is a general setting for the adjustment screws I can set them to? I have spark, and I see oil on the plug, piston, and in the crankcase.
Well I got the new cylinder. Had it honed and installed it. Compression is noticeably higher. But now it won't start. I got it to sputter a bit, but it won't run continuously.
It has spark, and the bowl is filling up with fuel. What else do I check? I took the carb apart and cleaned it. Everything seemed fine. How do I check to make sure it is actually pumping fuel into the engine? What is a general setting for the adjustment screws I can set them to? I have spark, and I see oil on the plug, piston, and in the crankcase.
Re: I now have compression and it still won't run:(
How much compression? "noticeably higher" doesn't mean much. If it was 40 before 60 is noticeably higher, * it is 50% higher but it still won't run with 60 PSI.
Bear 45/70

'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
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'84 Aero 125 X 2
'85 Aero 50
'85 Spree
'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
Re: I now have compression and it still won't run:(
I keep returning the compression tester to autozone. I didn't have a car today to run and grab it again. Probably won't tomorrow either. It feels solid. I get tired of kicking? Is that a unit of measurement?Bear45-70 wrote:How much compression? "noticeably higher" doesn't mean much. If it was 40 before 60 is noticeably higher, * it is 50% higher but it still won't run with 60 PSI.
Re: I now have compression and it still won't run:(
Without enough compression, everything else is a waste of time.
Bear 45/70

'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
Re: I now have compression and it still won't run:(
Here is the thing I do when trying to find out if my carb is fueling or not......twist throttle open and spray 1 second burst of WD-40 into throat ......if it fires and runs on the WD-40, but wont run without it, then carb is not fueling....................................remember not to overuse this method too much at one time.....it's just a test...never use starting fluid.......................
It doesn't waste much time
RideRed
<Helix><(2)Gyro S><Rebel><CB100><Urban Express><Aero 50>
"Live Large - Ride Small"
<Helix><(2)Gyro S><Rebel><CB100><Urban Express><Aero 50>
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- fightingplankton
- CB900F

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Re: I now have compression and it still won't run:(
check the service manual for your idle/air screw settings.
'86 spree
'86 aero50
'83 aero80
'86 aero50
'83 aero80
Re: I now have compression and it still won't run:(
That could be said for ANYTHING that is causing the issue. Thankfully though, I have time on my hands, and no car. So I am going to check everything else first.Bear45-70 wrote:Without enough compression, everything else is a waste of time.
Are you sure this will work? I have tried to light WD40 before with zero luckmotormike wrote:Here is the thing I do when trying to find out if my carb is fueling or not......twist throttle open and spray 1 second burst of WD-40 into throat ......if it fires and runs on the WD-40, but wont run without it, then carb is not fueling....................................remember not to overuse this method too much at one time.....it's just a test...never use starting fluid.......................It doesn't waste much time
Re: I now have compression and it still won't run:(
Ok, thinking about my last post, it has to be a gas/oil mix in the crankcase and on the spark plug. It mixes very little oil into the gas. My crankcase seems half filled with fluid. That would mean I'd see a noticeable drop in oil level. I don't. So I can only assume gas is getting there.
Re: I now have compression and it still won't run:(
Two things;
1) The compression tells you how physically healthy your motor is. An engine will fire with too much or too little gas, even with the timing off, but it will never fire with no compression. Basic mechanics here.
2) All you get when you ASSUME is to make an "* of you and me." Never assume anything with engines, you waste time and effort and frustrate the * out of those trying to help. Do the d*** test, it proves something, assuming proves nothing.
1) The compression tells you how physically healthy your motor is. An engine will fire with too much or too little gas, even with the timing off, but it will never fire with no compression. Basic mechanics here.
2) All you get when you ASSUME is to make an "* of you and me." Never assume anything with engines, you waste time and effort and frustrate the * out of those trying to help. Do the d*** test, it proves something, assuming proves nothing.
Bear 45/70

'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
Re: I now have compression and it still won't run:(
I don't mean to upset you here, but I cannot get the tester for some time. Maybe by this weekend. It will cost me a 45 dollar deposit I don't have, and my car is being used by somebody else for the week. There is no harm is checking other things such as the carb functioning properly. I completely understand where you are coming from, and agree with you, but I can't "do the d*** test" right now.Bear45-70 wrote:Two things;
1) The compression tells you how physically healthy your motor is. An engine will fire with too much or too little gas, even with the timing off, but it will never fire with no compression. Basic mechanics here.
2) All you get when you ASSUME is to make an "* of you and me." Never assume anything with engines, you waste time and effort and frustrate the * out of those trying to help. Do the d*** test, it proves something, assuming proves nothing.
- Wheelman-111
- Moderator

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Re: I now have compression and it still won't run:(
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: I now have compression and it still won't run:(
+1 and then you always have a compression tester. * I have 3.Wheelman-111 wrote:Greetings:
$45 Deposit?
Try This. The price used to be $10, but still pretty good.
Bear 45/70

'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
'83 Aero 80 X 3
'84 Aero 80 X 3
'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree
Re: I now have compression and it still won't run:(
holy s***. Thanks guys. harbor frieght isn't too far away too!
-
TiffanySpree
- Spree

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Re: I now have compression and it still won't run:(
The WD40 trick was true some time ago. Then after some time, they changed the formula and it is no longer combustible.
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1986 NQ50d Spree Tiffany green/white - wifeys. Currently modding to get more *!
Early head, exhaust port, intake manifold, intake pod filter, 2.75 rear tire, pulley mod.
1986 NQ50d Spree Tiffany green/white - wifeys. Currently modding to get more *!
Early head, exhaust port, intake manifold, intake pod filter, 2.75 rear tire, pulley mod.
Re: I now have compression and it still won't run:(
Have you tried putting some gas in the spark plug hole to start it?
1986 Spree/ Eve af16 swapped 65cc Prodigy vari 8g 9:1 Ruima gears
21mm OKO 42/100 32:1 45mph kymco zx exhaust
1994 Elite S 17.5mm Arreche, Daytona reeds, SEF ramp, pump plugged
1987 Elite SE50 af16 swapped
1989 Elite E SB50p
2003 Yamaha Zuma
21mm OKO 42/100 32:1 45mph kymco zx exhaust
1994 Elite S 17.5mm Arreche, Daytona reeds, SEF ramp, pump plugged
1987 Elite SE50 af16 swapped
1989 Elite E SB50p
2003 Yamaha Zuma
