Ok finally got the ext 580 efi going Again. Replaced the overbored pistons with a stock set of cyls and pistons off a another motor.
Compression on the motor that I bought was 120 before removing the cyls and pistons. It is now still 120 on my motor with them in it.
Started and ran fine last night. Ran it for about 30 mins or so. Rechecked the torque on the bolts and made sure no leaks anywhere. There were none.
Took it out today on the lake, about 6" of snow, slightly heavy packing snow. Ran great for about an hour. Then it would bog baddly at around 1'/2 throttle about 6k rpms and not get above 45mph
At one point it almost died completely, (remember its an efi) feathered the gas and it stayed running, but ride back to shop, was boggy around 30mph, with a lurch.
Took it out in front of the house for a clean out rip to see if it would speed up, ran like a raped ape, No issues, until I let off the gas to stop, slowed to a stop and as it idled down, it died, hard restart, replaced plugs with two new ones and it fired right up, brought her back in and it died again at idle.
Will restart fine, and idle fine, just after a run it will die out. Compression is still 120 on both, Fuel pressure is 35lbs on the gauge. The plugs come out slightly blk/bwn and a little moist.
Any ideas?
Compression on the motor that I bought was 120 before removing the cyls and pistons. It is now still 120 on my motor with them in it.
Started and ran fine last night. Ran it for about 30 mins or so. Rechecked the torque on the bolts and made sure no leaks anywhere. There were none.
Took it out today on the lake, about 6" of snow, slightly heavy packing snow. Ran great for about an hour. Then it would bog baddly at around 1'/2 throttle about 6k rpms and not get above 45mph
At one point it almost died completely, (remember its an efi) feathered the gas and it stayed running, but ride back to shop, was boggy around 30mph, with a lurch.
Took it out in front of the house for a clean out rip to see if it would speed up, ran like a raped ape, No issues, until I let off the gas to stop, slowed to a stop and as it idled down, it died, hard restart, replaced plugs with two new ones and it fired right up, brought her back in and it died again at idle.
Will restart fine, and idle fine, just after a run it will die out. Compression is still 120 on both, Fuel pressure is 35lbs on the gauge. The plugs come out slightly blk/bwn and a little moist.
Any ideas?