I have read with interest all the posts about non-starting John Deere's. I have a z425 with a briggs and Stratton engine that started having very low power this season. I did the usual servicing: fuel filter, oil, oil filter, air filter, and spark plugs. This made no difference. I then cleaned the carb linkages with some success. The mower never seems to be running at full power. I finally pulled the carb, but it appeared to be very clean. After reattaching the problem was even worse. I bought a carb repair kit and replaced all the parts, now it will not start at all. It backfires through the carb and that is about it. I did test to see that the solenoid actuated, but have not tested to see if it may be the problem. I have no repair manual and thus have not yet checked the valves or the fly wheel pin. Any thoughts?
Engine z425 will not start
- Thread starter daddydoc
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BBO
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I was thinking trash in the carb or a clogged fuel filter.
Ethanol in the fuel will deteriorate fuel line and cause pieces of the rubber to gum up the jets.
Do you use Ethanol free fuel?
I would replace ALL the lines if any of them are suspect, plus a new fuel filter.
Plus take the carb back apart to be sure it's all clean.
I did recheck the carb and all seemed good. I then tried priming from above and no go. I have since started tearing into the engine, even though I am a novice at small engines. Once the valve cover came off I discovered the problem.. all of the push rods are either bent or broken. I know I need to check the key to ensure it has not sheared off given this. I was able to get the cooling fins off easy enough and the central bolt on the shaft was easy enough to come off as well. I simply cannot get the top flywheel (may be wrong terminology) to come off. I know there is a seal and it is compressed on, but I can't get it to budge. Is there a special tool for this? Would appreciate any input.
Briggs 23 HP twin V engine
44L7770115B1
070910YG86398
Briggs 23 HP twin V engine
44L7770115B1
070910YG86398
A steering wheel puller will do it, just gotta find bolts long enough to fit....or you can have somebody help you by putting a couple pry bars under it applying pressure up, with the bolt loosened of you smack the bolt head with a good sized hammer and it will pop off
Thanks for the input
In case anyone sees this and is interested.... The no start was due to bent and broken push rods, both cylinders. Upon further investigation, cylinder #2 had a bad valve in that the valve guide had backed out of the cylinder head preventing full travel of the valve and bending the push rod. The strain from running on one cylinder finally got cylinder #1. That and the valves needing to be adjusted. Thus for no starts I would recommend checking the valves as well.