Engine not firing

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Liquifire76
Posts: 29
Joined: Mon Oct 17, 2005 12:00 am

Engine not firing

Post by Liquifire76 »

I have a 1976 Liquifire 440 that had no spark (burnt CDI), replaced with new cdi and now have spark but the engine still won't fire! Is there another electrical component that could prevent the engine from firing, even though there is spark!
This motor has not ran in 10 years, so I am sure that there could be other issuses, but I would like to know where to look next! It is definately getting gas as I put some directly into the cylinder! I am hoping to bring it back from the grave!
JDT
Posts: 5561
Joined: Wed Nov 21, 2007 1:00 am
Real Name: Todd
Location: Milbank South Dakota

Engine not firing

Post by JDT »

Basic requirements to run... fuel, spark ,compression.
You have spark but is it at the time? Plug wire switched around?
Compression... check it with a guage.
Todd
Todd Schrupp

Milbank SD
harleysportster
Posts: 2965
Joined: Thu Jul 14, 2005 12:00 am
Real Name: Pat Scott
Location: Southeast Pa.

Engine not firing

Post by harleysportster »

Liquifire76,
First off, buy a service manual, they are available.
A 2 stroke engine needs the following to run:
-Good compression, at least 90 lbs, fresh rebuilt around 120-130lbs.
-Good crank seals, pressure test required for accurate results
-Good spark, check using an in-line tester. Weak plugs will short out under compression
-Super clean carbs. The cleaning of carbs is a must when diagnosing fuel problems
-Clean fuel filters. There is one inside the tank and one external.
Since you engine has sat for 10 years a good carb cleaning is a must or serious engine damage could result
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
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