Hi everyone....i've seen how helpful everyone here is and hope someone can give me some suggestions. Here is what I've got.
I bought an older but in relatively good condition JD 165 hydro from a guy around the corner. He was the only owner, had it serviced by the local JD dealer every spring. One day it wouldn't start. He took it to the dealer...they got it going, he brought it home and mowed the lawn. The next time he goes to mow, no start again....back to the dealer, and this time he goes home with an X300. (I know the dealer....they rather sell than fix) So i bought it, I don't mind a winter project....
Everything seems to be working right, but it just won't start. It gives nice puffs of smoke through the carb when the air cleaner is off.
So I start with the basics...spark? Check...just in case i got a new plug...still doesn't start, but now really pops back through the carb. Check the fuel, pump works great and plug is soaking wet....just in case give a shot of gas in the carb and in the spark plug hole....nothing. Compression...90 pounds. Pull all the shrouds off and check the flywheel key...which is good, and the coil air gap...good. Pull of the head...check cylinder...seems to leak a tiny bit of oil with each stroke from around the piston...and check the valves...intake doesn't have enought clearance (just) so pull the spring and valves, lap them, adjust clearances and reinstall.....
At this point I figure i'm good so reassemble everything and give it a whirl....same popping through carb....agggghhhh. This time, I give a shot of oil in the intake.. (saw somewhere that this can sometimes seal a bad intake valve long enough to start engine...and help diagnose the same)...no change.
Went out and bought a cylinder leak down tester (the nice part about working on things yourself...the ability to justify new tools
Did a leak down test...can hear whistling through the carb...nothing through muffler, but when i pull the top off the dipstick I have a oil volcano.
Pull it all apart again...maybe i made a mistake....check valves seating...seems to be good to me (i checked with a feeler gauge and by backlighting them in a dark garage) They seem to be seating perfect.
I'm stumped. I'm inclined to rip apart the engine and see if maybe the camshaft is out a tooth (bad timing). I've also been considering the spark....maybe its worth it to try a new coil before i rip it down totally. And then the leakdown test...how am i hearing air through the carb and past the rings if i have 90 pounds compression....should i just do a rebuild?
Sorry about the length of this post...any input would be greatly appreciated.
G
I bought an older but in relatively good condition JD 165 hydro from a guy around the corner. He was the only owner, had it serviced by the local JD dealer every spring. One day it wouldn't start. He took it to the dealer...they got it going, he brought it home and mowed the lawn. The next time he goes to mow, no start again....back to the dealer, and this time he goes home with an X300. (I know the dealer....they rather sell than fix) So i bought it, I don't mind a winter project....
Everything seems to be working right, but it just won't start. It gives nice puffs of smoke through the carb when the air cleaner is off.
So I start with the basics...spark? Check...just in case i got a new plug...still doesn't start, but now really pops back through the carb. Check the fuel, pump works great and plug is soaking wet....just in case give a shot of gas in the carb and in the spark plug hole....nothing. Compression...90 pounds. Pull all the shrouds off and check the flywheel key...which is good, and the coil air gap...good. Pull of the head...check cylinder...seems to leak a tiny bit of oil with each stroke from around the piston...and check the valves...intake doesn't have enought clearance (just) so pull the spring and valves, lap them, adjust clearances and reinstall.....
At this point I figure i'm good so reassemble everything and give it a whirl....same popping through carb....agggghhhh. This time, I give a shot of oil in the intake.. (saw somewhere that this can sometimes seal a bad intake valve long enough to start engine...and help diagnose the same)...no change.
Went out and bought a cylinder leak down tester (the nice part about working on things yourself...the ability to justify new tools
Did a leak down test...can hear whistling through the carb...nothing through muffler, but when i pull the top off the dipstick I have a oil volcano.
Pull it all apart again...maybe i made a mistake....check valves seating...seems to be good to me (i checked with a feeler gauge and by backlighting them in a dark garage) They seem to be seating perfect.
I'm stumped. I'm inclined to rip apart the engine and see if maybe the camshaft is out a tooth (bad timing). I've also been considering the spark....maybe its worth it to try a new coil before i rip it down totally. And then the leakdown test...how am i hearing air through the carb and past the rings if i have 90 pounds compression....should i just do a rebuild?
Sorry about the length of this post...any input would be greatly appreciated.
G