Honda GXV530 intermittent problem

[GetTechnicalWithJd]

Hi All,

I have a buddy who has a Honda GXV530 which he is having an issue with.

The engine runs fine and the out of the blue it 'misfires'. They determined that when the engine was 'misfiring' it was only running on one cylinder. They checked compression which was good on both cylinders and then checked spark and found that there was no spark on the suspect cylinder. At the advise of Honda they replaced the ignition coils and sparkplugs (resistor plugs) but the problem persists with intermittent loss of spark.

They have tested the engine with all the tractors wiring removed and the diode line between the coils removed. Still spark comes and goes on the number 2 cylinder.

Any suggestions?

 

[pugaltitude]

Did the new coils come with plug terminal and caps (rubber) or have they got the resistor style plastic screw ones?
The plastic ones are normally on the Honda GXV610/20/30 engine.
Change the plastic to rubber as these can breakdown.
If its losing spark then it can only be flywheel or coils if all elecs disconnected.

 

[robert@honda]

Start by checking the resistance of the primary and secondary coils...note the primary is measure in ohms, while the secondary is measured in Kohms:

The #1 coil is the one with the shorter lead, the #2 coil has the longer lead.

Double-check the air gap between the coils and the flywheel:

 

[reynoldston]

A few years back I had a repair job that the engine acted same way you are describing. After much time looking for the problem I found a pinched primary wire.

 

[GetTechnicalWithJd]

Did the new coils come with plug terminal and caps (rubber) or have they got the resistor style plastic screw ones?
The plastic ones are normally on the Honda GXV610/20/30 engine.
Change the plastic to rubber as these can breakdown.
If its losing spark then it can only be flywheel or coils if all elecs disconnected.

They have rubber. I will get them to test the coils as robert suggests.

Will let you all know what we find.

 

[GetTechnicalWithJd]

Start by checking the resistance of the primary and secondary coils...note the primary is measure in ohms, while the secondary is measured in Kohms:

The #1 coil is the one with the shorter lead, the #2 coil has the longer lead.

Double-check the air gap between the coils and the flywheel:

Thanks for the info.

 

[Ducatiman]

Start by checking the resistance of the primary and secondary coils...note the primary is measure in ohms, while the secondary is measured in Kohms:

The #1 coil is the one with the shorter lead, the #2 coil has the longer lead.

Double-check the air gap between the coils and the flywheel:

I'm having similar problems with a Countax mower which has this engine.

Couldn't get a spark from either coil so tested the resistance values and both look fine. I put the right hand coil back on, set the gap at 0.015" and straight away got a good fat spark. Tried it with the diode cables off and on and it made no difference so I'm assuming that is ok. Swapped plugs to see if that made a difference but no go on the left cylinder.

The engine actually started and ran on just one cylinder and didn't sound bad, I'm begining to wonder if it ever ran on both cylinders since I bought it second hand.

New left hand coil on order so it will be interesting to see if that helps.

 

[Ducatiman]

New coil fitted and it is now running as it should! Just shows that the coil resistance isn't a fail safe method of assessing the coil.