Honda Mower GCV160 won't start!

Model:HRR2166VKA, bought at HD 1 year ago. Was "factory reconditioned" though it appeared new to me when I bought it. No issue in year 1. Mower very easy to start in fact. I estimate about 50 hours of usage in year 1. Mower outside for the winter but away from elements.

This year: used the mower three times with no problem. During the 4th mowing session, the mower died as I was mowing. Checked for gas, no problem. Restarted after three pulls. Died while running again about 10 minutes later. Has not restarted since and that was 4 weeks ago.

Changed spark plug. No effect. Old spark plug was dark.
Changed ignition coil. No effect.
Examined carburetor: looks clean, blew compressed air through bottom hole and seemed to flow fine. Reinstalled and no effect.

If I take the spark plug out and leave it outside while I pull the cord, I don't see a spark. Am I supposed to?

When I take the spark plug out, I can smell fuel.

The air filter is clean. I tried starting it with air filter out. No effect other than sound change.

When I changed the ignition coil, I got a tiny bit of white smoke out but it only did it twice. Otherwise, there is no smoke coming from exhaust and no corresponding "explosion" in the piston though you can hear the motor moving as a result of starter pull. No backfiring of any kind. The same fuel runs fine in another mower and I checked the oil, there is plenty and it is clear.

I have not squirted gas in carburetor and tried to start but I did notice that there was fuel in it when I removed the bottom screw and that the flow was unimpeded going through the jet.

I also took out the kill switch by disconnecting from the coil (both old and new). No effect.

I love this mower but I am at a loss. Thanks in advance for any help.

 

If you take the spark plug out you should be seeing a spark. have the side of the spark plug on th side of the engine block (make sure its touching metal!) and try to pull start the mower. Do it in the shade or at night for a clear view of a spark, though you should see it in the light of day. if you don't see anything, its probably the plug or a chink in the ignition wiring, or simply a loose spark plug boot.

 

Update. When I grounded the plug to the chassis, I saw a spark by manually turning the magneto. I also tested the kill switch while I was at it and it is also functional. So I have a spark.

Not sure what direction to go.

 

Try putting a little gas into the spark plug hole and see if it will start for a moment.

 

Update. When I add 1 teaspoon of gas directly into the cylinder, the mower does not start. When I remove the air filter, I can hear the engine backfiring a little. Some heat can be felt so that tells me there is some firing going on.

When I place the air filter back on and place my hand directly in front of exhaust, I can feel air coming out of exhaust if I pull the pulley.

Summary so far. I have spark. The engine turns over. The carburetor is clean. The engine seems to fire when the air filter is off but not when the air filter is in.

Ideas anyone?

 

Update.

Changed oil. Drain gas and put new gas in. Cleaned carburetor using spray but did not take carburetor apart.
Sprayed starter fluid into air intake fuel valve off. Pulled: no good.
Spayed starter fluid directly into cylinder. fuel valve off. No good
Turned on fuel valve. Pulled: no good.
Removed air filter with fuel valve on. no good but engine stuttered for about 2 seconds and white smoke came out of exhaust.

 

Is the oil level overfull and does the oil smell like gas?

 

The oil level is fine.

Update #5 Removed the muffler and sprayed carb cleaner into exhaust valve. Noticed that valve was moving and stem was relatively clean. Buttoned it up and tried to restart. Nothing. Mower is close to making it to curb considering the cost of new one ($300) and how much time I have wasted.

At the end of the day, the timing appears to be the problem but I am not equipped to fix nor do I know where to begin. If one assumes that HD makes $75 on the mower, subtract $5 for shipping and $50 as profit for Honda, you are left with less than $175 of cost to make the entire mower. At that price, these machines are not meant to be long lasting nor repairable.

 

To adjust the valves you would need to opne up the engine, though i wouldn't know specifically you would need to do for a overhead cam. Sorry. If you get a new mower, go to consumerreports.org to check on lawnmower ratings. Generally, hondas last for 10+ years. I once had a briggs powered lawnmower that lasted for 35 years, its worth getting a good one.

 

This mower is out of warranty? This should last a long long time and is probably an easy fix. I'd say at this point, the flywheel key could be sheared. When it died as you were mowing, had you recently hit a root or object? The flywheel key is easy to check. It's what sets the timing.

 

cheese has a very good point, considering that the key if warped will mess up the timing as well as it is very easily overlooked when fixing an engine.

 

A- Did not hit anything, at least not when it died.
B- Where is this key? I am assuming that you are calling the magneto body the flywheel. I don't see anything in there that is removable or bendable. The magneto body is looks lie cast Al and does not have loos components. According to what I find, you are talking about an elliptical piece but I can't see it.
C- This is my 5th mower and I have a blower. Small engines should last years (as most of mine have). Honda give a good cut but running into this kind of issues after one year is crazy.
D- Mower was bought recon. Most likely a return as it looked new to me at time.

 

Try a warrant if you can. the flywheel key is a where the flywheel meets the driveshart. Its dimension are about 1/8 x 1/8 x 1/2. its job is to make sure the flywheel is in the right place on the driveshaft.

 

Let's see. Looking at the mower from the top, I see the flywheel with its 4 oval rods that stick out to engage the hand pulley. In the center is a 19 mm nut. I don't see anything else. Is the key underneath the flywheel? Do I need to remove it? The 19 mm is in there very solid.

BTW: bought a power washer today and a equivalent price, picked the Subaru engine over the Honda engine!

 

Subaru makes a good engine, but you won't be doing yourself any favors by eliminating honda from your list of engines to buy. They make many of the most dependable and longest lasting engines on the market.

Buying a reconditioned one isn't the best (or a fair) way to judge the quality of a product. Some products are reconditioned by contracted companies. I don't know if hondas are or not.

You have to remove the flywheel to check it.

 

Will do, thanks for info. As dependable as Honda is, there are hundreds of posts about engine timing and stuck valves. The confluence of low price (cheaper raw material) and emission control (tighter specs on valve tolerances) is probably a bad one for most small engine makers.

 

Pretty accurate assessment I'd say.

 

When I bought my Honda mower at Home Depot last year, it came with a 3 year warranty. Call Honda. This is their problem.

 

Take the valve cover off,and check to see if the timing belt has come off the cam gear.Be careful in removing the cover,honda uses a bond three sealant to on the cover instead of a gasket.They also recommend replacing the cover it is easily bent in removing.The cam gear is plastic it could be broken,or just the belt may have come off.UTUBE has a video in how to line up the cam gear with the crankshaft.Just type in HONDA GCV160 timing gear replacment.Hope this helps.

Jerry

 

To Jfinn: Mower was bought reconditioned so warranty was voided even though mower was new as far as I could tell.
To JSouth: I will do as told. I can't find the timing video you are talking about. Can you post the link?
To thedancingman43: I have not yet taken flywheel off but will do that as well. 19 mm nut is glue and very difficult to remove.

Update to follow.

 

EUREKA! When the OHC cover was removed (don't forget to remove the oil first!), I immediately saw that the intake valve was stuck in the open position. I removed the spring and gently forced the valve to close. I added carburetor cleaner to the piston and gently rocked the valve back and forth. Placed the spring back in and everything looks good when I move the flywheel by hand.

Conclusion: the valve got stuck while running, thereby flooding the engine. When I tried to restart, the engine would be flooded with no compression since the valve was open. With the fuel valve off and the air intake wide open, I could get the engine to occasionally backfire, giving the impression that I was Oh so close!

Next step: buy Honda-bond compound to reseal the OHC cover. Perhaps buy a new cover although mine does not look too bad. Look for the root cause of the valve stuck up process (suspect tolerances) and look for other ways to clean the valve while the OHC cover is off. Button it up and get my son to mow the lawn. More later.

 

This is the only way I know how to post a link.Go to GOOGLE,and type in video how to replace a camshaft on a honda GC160.Hope this helps.

Jerry

 

Final update. Resealed the valve cover, waited 24 hours and she started on the first pull! Burns a little white but I think that's because of the addition of Mystery Oil to the fuel. I mowed and all is well. Thanks to all comments.

According to Honda, "bad" fuel is the root cause of valve jams. You can even find a field note on how to repair (by basically doing what I did here - remove cover and force valve to open and close). Gasoline is essentially hexanes and other light molecules so I suspect that additives are the culprit here (anti-knocking, cleaning compounds, pollution control etc...). These vary by region and retailer and time of year so good luck figuring out what's what. There are reports that using synthetic oil or mystery oil helps. Time will tell.

For future reference, I offer here a simplified trouble-shooting guide for this particular engine with NO START condition.

1- Verify that exhaust is not blocked (by insects or rodents). Visual test.
2- Verify that fuel is present and valve is open.
3- Take off spark plug and verify that spark is present (hold the spark near the mower body). Verify both with and without kill switch. Replace ignition coil and spark plug as needed. Gap is 0.030" (pre-gapped if it says Honda on package).
4- Clean carburetor (without disassembly) using cleaner in a can. Try starting with starter fluid.
5- If still not start, tests the valves. The exhaust valve can be inspected by removing the entire muffler and shinning a flashlight into the cylinder. The intake valve can be inspected by removing the entire carburetor assembly (take picture as there are many loose pieces) and look into the cylinder. You should see a little movement (the total travel is about 10 mm).
6- To loosen jammed valves, drain fuel and oil (don't forget carburetor nut at bottom) and remove the cam cover (the thin aluminum plate that says OHC). Use a delicate blade to pry it loose. You can reuse the cover but Honda recommends that you replace it with a new one. You may want to buy the cast-Al version (GCX160). The valves will be exposed and it a simple matter of gently forcing them to open and close, with lubrication (oil or other cleaner) and heat (this according to Honda but mind safety if you do). It can be necessary to remove rocker and spring but I was able to do it without that. The valves will open and close when you turn the flywheel by hand. the range of motion on both should be identical. While the cover is off, inspect the timing belt. It should be taunt and well engaged. You can also inspect for proper timing (go online to find the right info on timing notches. Basically, you will align the flywheel to a preset position and look on the cam wheel for proper alignment mark. When both valves are loose and you are satisfied with timing, clean the mating surfaces and reinstall cover using new silicone compound and retry after 24 hours. Don't forget oil and fuel!
7- If the mower still does not work, you need to think about checking for the flywheel key which is located UNDER the flywheel. You will need a lot of elbow grease and a 19 mm wrench. Last resort kind of deal. The key is susceptible to be broken if you ran into a solid object like a brick or tree root.

 

Hi Fredct,

I have exactly the same problem with a 4-year old Karcher pressure washer with Honda GCV 160 engine. I was able to start it and used it to power wash my deck for 2 days last week. The washer had normal good high pressure. I used it the last time until it ran out of gas. After I refueled the gas tank with new gas, I could not start the engine right after and ever since that last use. I had been searching for info in the internet and found your thread is talking about exactly the same issue I have but mine is a pressure washer.

I've checked every obvious things that reported could have caused the problem:
Oil level was fine
Fresh gas
Spark plug gap was correct and cleaned up. Spark plug test done and had spark. Plug had fuel after pulls.
Air filter is clean.
Switch was on and fuel value was on.
Starting fluid was sprayed into the carb (did it 3 times)
All in all, the engine didn't start. The last two times I tried, I heard small backfire noise.

I have not tried to do your bullet points 4, 5 and 6 because I am not that mechanical. Please tell me the difficulty level for cleaning the carb and removiing the cam cover to loosen the value. More details or sources of details on these steps are much appreciated.

I've tried to remove the cam cover and just went as far as loosening the 4 screws because I had a hard time prying it off and was concerned about damaging it (I saw some oil/gas(?) leaking after screw were taken out). So far I feel very frustrated with this engine not starting problem and am about to give up. I don't want to spend any money in parts and tools even if I can do it myself because it's only a $250 piece of equipment. I saw a lot of posts on how bad Karcher washer pumps were and my washer has already had a small water leak from the pump.

Thanks a lot for any help and advice from anybody out there.

Evergreen

 

Evergreen,

Step 4 involves unscrewing the carburetor and spraying cleaning fluid (do this outside) from the side (air side) and the bottom (remove the bottom 10 mm screw). While the carburetor is out, you can look into the piston itself (i.e. look inside the motor through the carburetor opening and see if you see cam movement (use a flashlight) as you gently turn the flywheel. REMOVE the spark plug to avoid spurious ignition. You do not need to take the carburetor apart unless it is totally trashed (very black with physical gum all over).

Step 5 is explained above. To see the exhaust valve, remove the muffler and spark arrestor and shine a flash light into then engine body. Again, you are looking for movement of the valve stem as you gently turn the fly wheel.

Step 6 (And I think this is your problem here). Drain all fuel. Drain the oil. Remove the 4 screws. The cover will not come off as it is glued using high temperature silicone. Using a sharp knife or small wood chisel, insert the blade between the cover and the engine, right where you see the silicon bead. Gently break the bond and repeat in other spots. You will need to make make several "cuts" before the cover comes off but come off it will. Be careful if you intend to reuse the cover. A small quantity of oil will come out so place rags under the cover to avoid a mess. Place cover aside. You are now looking at the 2 rockers, the 2 springs and the 2 valve stems. Under the valves, you will see a black dented wheel and the timing belt. (Step 6). Now either using your fingers or by turning the flywheel, see that the valves open and close as the rockers move back and forth (one at a time). If one is stuck (most likely your case and most likely intake valve (right one) in open position), you will need to use pliers to knock it loose. To do this, you may want to remove the washer that pushes on the spring. Have someone push the spring in while you pull up the slotted washer from the stem. Now you can use nose pliers to move valve back and forth (it may not move at all initially). Spray carburetor cleaner on the stem as you move it back and forth. If necessary, you can use gentle heat, either directly on your work area or through the intake (with carburetor off). Move stem back and forth for 5 minutes. Squirt a little oil on the stem if you can as you finish the job. Before button it up, replace the washer and gently turn the flywheel and make sure that each valve opens and closes. If that's happening AND the timing belt looks normal to you, you are probably done.
Using a gentle tools and a gentle touch, remove all silicone residue from the engine block. In other words, scrap it off! Do the same for the cover and if necessary, bang it back to straightness.
Buy high temperature silicone (about $6 at any auto part store, they will know what you need, no need to buy a branded product). Apply a small bead inside the slot in the cover. Make sure that it is a continuous bead - don't leave holes. Screw the cover back in to finger tight. Wait 60 minutes and re tighten 1/2 turn or so. Wait 24 hours, add oil, gasoline and watch here go.

Water leaks are another matter, specially on the high pressure side. Considering how much you paid, I would think about leaving that alone, provided that the compression at the end of the hose is still good.

 

Evergreen,

A careful novice can absolutely do step 5 and step 6. Step 7 and 8 are more esoteric and may require a trip to your small engine repair shop. That said, I don't think that's your problem.

 

Hi Fredct,

Thanks a lot for the detail steps and advice. I'll follow your advice and see how far I can go.

Evergreen