Question
Valve Seats
Hi, I have a Honda GX160 (GC02-3659731) that I'm having a problem with. I checked valve clearances today and had to adjust as both intake and exhaust clearances were too tight. Then I decided to remove the cylinder head to see what was happening inside.
The main problem with the engine has been 'surging' as in running unevenly and constantly trying to find a balanced rpm when operating. I had found that giving it more choke when working evened things out a bit but as the engine gets working (used for a garden cultivator/tiller) the problem returns. I have also replaced the carburetor, spark plug, air filter and oil recently.
As I set about removing the cylinder head, I noticed that the valve springs were easy to remove with my finger? Is this normal or are they worn?
Regarding the attached photo, what's the best way to overhaul this? (I have other close-up photos of the valves as well) Do I have to bring this to a repair shop?
Thanks.
Kind Regards,
Padraig.
AnswerYou can use a valve lapper and lapping compound to clean up the valve seats but the exhaust valve seat looks pretty rough. I would use a Neway valve seat cutter to re-cut the seats, and then lap, but the tool is too expensive for the home owner.
The springs aren't that strong, it's a small engine, but finger loose is pretty loose. I would price new springs or use some washers to shim them.
As for the surging, 99% of the problems are caused by dirty carburetors. You need an air compressor to really blow out all the carb orfices/holes to make sure they are clean. Sometimes I have had to clean carb two or three times before I got them to work right.
The problem with tiller engines is that they are used in the harshest conditions, dust. This micro-duct can clogg the very small carburetor orfices and cause the carb not to work.
Does the engine burn oil?
Eric
