This saved me, same thing, stuck intake after not running it for a few months. It was even more stuck than yours, but only till i broke it free. It wasn't just moving slow, it wasn't moving at all. Then POP, came free. Was still very sticky at the top and bottom of travel so I used some Ballistol to lube it up and exercise the valve until it ran smooth. Fired right up after that. Thanks for this.
Quoc, Thanks so much for posting this. My same valve was stuck, and through your video, I was able to free mine and get lawnmower working. Wife is happy.
You are most welcome Shinryn. I listened to one of the commenter on this post and is now adding a few drops of 2 cycle-oil to each fill up and my mower. It hasn't degrade the power at all and I haven't had any problem since this video was made. The mower has been starting with one or two slow pulls since then.
If your intake valve sticking open is anything like mine on my GCV160, I could get it unstuck but it would only last for one cutting. Go to start it a week later and the same thing happens. After watching numerous videos about this intake/exhaust valve sticking open problem I decided enough is enough. HERE IS THE PERMANENT FIX: Pull the carburetor and pull the spark plug. If the engine will run, try to get it hot before you do this. Fill the cylinder and fill the intake port full of transmission fluid. Work the valves up and down and leave sit overnight. Work the valves in the morning and pull the rope to get as much fluid out that you can. Install the plug and carburetor. Start it up. It’s going to smoke like hell. Five cuts later, no more stuck open valves.
Thank you for this video. I just fixed a GCV 190 engine in my pressure washer. I had the same issue, except the exhaust valve was stuck on mine. Cranked on the first pull afterward.
Two part problem. The first is that the valve seal has worn out, allowing the oil to be past it, and it should be replaced with a new seal. The second problem is that fuel has varnished the valve stem from lack of use, and someone was not changing the oil at least yearly/ making sure there was enough oil in the machine. So since your dealing with fuel varnish and oil carbon (in part from the leaking seal, and the oil not changed enough/kept high enough to keep the channel clean), the quick way to solve the problem is as follows. Pull the carb to give it a good cleaning to resolve the varnish problem in it to start with, then since you have the intake passage open when doing the carb clean, you can use WD-40 on both sides of the valve to clean it stem and the head passage as well. Do not use SS wool to clean the stem, since it just going to scratch the stem. Just use little WD-40, lint free cloth, and compressed air to clean the channel and valve stem. Note: use a piece of strong cloth paper towel pushed into the intake passage toward the piston (end sticking out so you can pull it when your down), so it wicks the excess fouled WP 40 from reaching the piston and valve seat, instead of being forced there via the compressed air. Now , use a New valve seal, and if you have a leaking governor shaft since Honda passed on installing the seal on lawn mowers, install a seal on it as well. Also, take the time to nylon scrap the old RTV off from the head and cover, and give the new RTV a day to dry before you you add new oil and use the mower. And no, Honda does not use a Valve seal on the exhaust side. As for the way that the valve head section is oiled, its from the slinger on the piston connector tale that slings oil to the vavle compartment, which the vavle cam helps to distribute the oil as well in that area. I bring this up, since if you crack off the piston connector tail when installing a piston, you will need to replace the connector rod.
Trust me I've been working on engines for 25 years or more. A tank of 40-1 2 stroke will not hurt your engine, one time a season. The valve on my Honda was sticking every other time I mowed my lawn , the mower was only a year and a half old. If you look there are forums for this particular problem on this engine. I did this one time and problem fixed, 5 years I haven't had another valve stuck. And my mowers runs like a new and never seen a shop.
Thank you! Thank you! Thank you! Put away the mower a couple of weeks ago and it was running fine. Today it had no compression and wouldn't start. After checking everything else I took off the valve cover and the intake valve was pushed in. I removed the rocker arm and used a long nose to pull out the valve a little, prying against the cylinder. I put some parts cleaner and oil on it and pushed it in and out until it was freed up. Adjusted the valves and put it back together. Started right up and ran like a champ. Thank you!
I took the advice of a person who commented on this video and have been adding six, seven drops of two cycle oil to the mower gas tank every time I fill it up. It’s been starting like a champ ever since. Mostly with just one light pull.
Thanks for the video! Found out today after taking the valve cover off that the exhaust rocker arm was broken and I didn't think it check and see if the valve was stuck. I'll check tomorrow but I'm sure the exhaust side is actually stuck which is why it broke the rocker in the first place. It's a 2008 and I've taken care of changing the oil twice the past two years but don't think the guy before me did. Pretty sure it was either burning oil or leaking oil from the valve cover. I've been constantly adding oil to the mower so hopefully this will fix all my issues. Thanks again and happy new year!
Thanks very much for this Quoc, I have the exact same problem, just diagnosed it after trying everything else, Will give it a go right now. It's to be hoped that Honda have rectified this common fault I will just add, I've just fixed it, but I used carb cleaner on the valve stem which dissolves the gum instantly so you can soak it up in some tissue. There is no valve guide as such unlike on an auto engine, so the valve stem is visible inside the inlet tract and you can see the state of it when you remove the carb
Thank the ethanol in your fuel for this. It gets old quick and these OHV engines can't handle even slightly stale ethanol blended gas. Ethanol carbons up the intake valve which makes them stick. Use only fresh fuel or non-ethanol fuel only.
I had the same problem on a pressure washer with this type of Honda engine; The fuel air mixture flows around the intake valve stem and can gum it up, fuel stabilizers/treatments can help. I took the carburetor off on mine to get to the intake manifold and flossed the stem with a piece of string while spraying with carb cleaner and moving the valve stem up and down. Then I poured a little motor oil on the rocker arm end; not sure how good the oil feed to the valve stem is with this design...
Do u have a part two of these video? If so how i can find it.i have the same problem in a same engine...my lawn mower dont start ,i dont know what else to do.
I think my exhaust valve isn't being pushed up enough because their is a huge gap when you try to set the valve clearance its impossible because the adjusting bolt is too short and comparing the spring to the intake it looks like its shorter. Im sure they are both the same length.
Did that mower have a starting problem where it almost ripped your arm out ? I have a Honda gcv160 on a power washer that I think has the same problem. Lmk
I had the same problem with the same engine very badly over and over. I started burning a tank of mixed gas (two stroke oil) I use in my my weed eater and I haven't had a stuck valve in years.
I have no idea. As long as there is still a quarter inch of the valve stem sticking out, you can grab it with a pair of pliers and and pull it back out.
Wanted to know if anyone has noticed on the gcv190 if it is normal for the exhaust to get red hot just noticed it last night when it got very dark, I’ve also noticed a small smell, just wanted to see if anyone else has ever experienced this?
I would check the valves and make sure they are in specs. If at TDC before the spark plug sparks and the exhaust valve is off and is not sealed completely, some of the explosive gas would escape through the exhaust valve and to toward the exhaust which would make the exhaust have a high temperature. I dunno, I'm just guessing. Somebody chimes in please.
I'm not a mechanic but I would open the spark plug to have access to the cylinder chamber and visually see the piston can move up and down. Then I would open the valve cover and make sure they are open and close correctly. If those two items are ok then may be there is a failure in the piston rings, the piston itself or the cylinder wall. You can only verify that if you take the engine complete apart I would think. Best of luck to you.
I just had the same issue. Less than 20 hours on it and it blew out the valve stem seal and prevented the valve from moving so it broke the weakest link. The rocker arm.
@@chriscostlow4210 I bought some special high temp loctite made for close tolerances and put it on there and tapped it back in. Then around the head of the valve guide, I put some JB Weld for extra insurance. I have ran the pressure washer about 4 hrs since then without issue.
The reason the stem is coated with crap, us because the valve clearance 0.006inches was wrong for a long time..combustion gases got in there cause timing was wrong, and when the chamber gases exploded the valve wasnt seated closed..probably gonna need to remove engine cover, crank and piston and remove carbon build up at the top of the chamber, and grind the valves with lapping compound. The valve must completely seal, or your just wasting your time.
Good point.I think your analytical reasoning is spot on. That the only reason fuel and get to the stem is when the valve ring not completely closed. I will take your reconditioning of the valve and valve seat recommendation into consideration. thks
@@quocducnguyen well that's wrong you should change it's by the hours used Honda put out the times in hours. less just say you run it 150 a year that's to long on my Honda it says every 50 hours. But it's yours rebuild as often as you like it's only money and time
@@L0WRYDER Ok thanks. Will do. That is something I didn't know. I thought I read somewhere that you should change oil once a year. As is, I think I'm under 50 hours a year as it takes about 40mins for the front yard and about 10mins for the backyard and I don't cut everyweek of the 52 weeks a year but thanks for the info. Have a great day!
