Question
Cylinder
Hi John,
I have been searching the site for help with my mower and it looks like you have some knowledge with this type of engine.
31F777-0162-E1
This is on a Toro 17-42Z - model 74350, ser. 240000772.
My biggest beef is that this thing has been going through too much oil. Additionally, it has gotten more difficult to start and actually had been easier to start with the choke off. Last year I had some problems with backfiring and a few good clouds of smoke. A couple of times the breather hose popped off and seemed to get oil everywhere. (I may have overfilled the oil a couple of times, having to always fill it up.) It was definitely leaking oil somewhere though. Oil was dripping off the bottom of the engine onto the mower deck. I wasn't sure if it was coming from the head gasket or rocker cover gasket. Oil was caked around the spark plug but could it be coming out of there? It just kept raining last year and I had to keep mowing. No time to try and fix it. Now I am trying to fix it before the grass really gets growing and gets above the knees.
So I pulled it apart to try and get at the problem.
Spark plug threads were oily, and the plug was very dirty. Maybe some carbon buildup.
Didn't see anything too interesting under rocker cover. Had to pick up some guages for adjusting valve clearances so I left that for now.
Removed head. Creamy orange puddle in cylinder. Lots of carbon on top of the piston. Valves and head caked in carbon. Looks to me like the seal failed between the cylinder and push rod galley.
I am hoping I can clean the piston and valves and put this thing back together with a couple of new gaskets. Am I on the right track here? I'm not even sure of how to clean these parts. Do I need to remove the valves to clean them and do I have to worry about scratching / damaging them or the area they seat?
Sorry about the book I just wrote. I just wanted to give you all the details up front, rather than you having to ask me a bunch of questions.
I have additional pics if that helps. It only let me post 1 I guess.
I really appreciate your help.
Thank you,
Stuart
AnswerYes, this engine has a history with blown head gaskets, and your problems are classic, just knock off the carbon with wire brush or scraper, clean it up as good as you can, and reassemble with a new head gasket.
Creamy oil means moisture in the oil, and orange sounds like broken down oil, like 10w40, so replace the oil with sae 30, and you should be good to go, if the paper filter got oil fouled, it will need replaced too.
Fish
