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Greetings:

(I searched before I posted)

Honda GCV160 motor won't start. I'm not a mechanical genius, but I've "turned wrenches" for a long time. This is what I've done/know:

1. Won't run on carb fluid or starting fluid.
2. Cleaned carb thoroughly (trust me, that ain't it)
3. has what I consider to be good strong fire at spark plug.
4. Motor has no compression using tester.
5. Pulled cam cover, ZERO valve clearance on exhaust valve (compression release working?) About 0.006" on intake.
6. Can't find timing marks or instructions on how to check time, check flywheel key.

Motor is on a 3 year old pressure washer that otherwise is perfect for me. I'd appreciate any advice you can offer.

Hello hppants: Set the valve lash to the following.

Intake valve lash: (0.006 +/- .002 inch)
Exhaust valve lash: (0.008 +/- .002 inch)

Then perform another compression test and report back. Here is a procedure to follow as well.

I'm cross posting information to this thread from another - in the hopes of getting help.

Is it possible that the exhaust valve "adjusted itself" to zero clearance? I've never heard of that happening on a "screw and nut" style of valve train. NO ONE has been into this motor (I bought it new) before.

Exhaust has ZERO clearance now.

Looking at it from the top (flywheel), the cam pully has the decompression "rod" in the right most position in the slot. I can easily slide it to the left, and if I let it go, it will slide (very slowly) on its own to the right. If I hold the rod in the left side of the slot, and turn the motor, I don't develop any clearnance in the exhaust valve. That is concerning to me. If the exhaust valve won't seat, I'll never get compression.

I haven't pulled the flywheel to see if the key is sheared.

(scratching my head)

Thoughts?

Thanks in advance.

It's quite rare to find a sheared key on a Honda. I'm willing to bet that if you have zero clearance and zero compression, you actually have a broken valve. With the head of the valve broken off, the valve stem is spring loaded, so it will butt up against the rocker arm. Even if you adjust the tappet, you will find that you still have zero clearance. If so, most likely damaged the piston also. If you were able to replace the valve and piston yourself, it would be cost effective. If you have to take it to a servicing dealer, buy a new engine or pressure washer.

Interesting - seems that if the valve broke, wouldn't the valve be attempting to float around in the combustion chamber? I'm not hearing anything unusual - wish I had one of those "pen light cameras" to look in there.

Bent valve is sounding more likely. Or maybe a bent rocker arm. Maybe I could check that out.

On this video - at 4:29, this is the position my decompressor is in for my cam pulley. And clearly, this motor has clearance on the exhaust valve.


Doing a valve job (and potentially engine rebuild) is beyond my capability. I was willing to tackle changing the cam pulley, but that's about my limit, I think.

Disappointing - pressure washer was only a couple years old....

If the head broke off of the valve, it is most likely imbedded into the top of the piston. If it wasn't, the engine would not rotate 360 degrees because there is not enough internal clearance.

hppants said:

Interesting - seems that if the valve broke, wouldn't the valve be attempting to float around in the combustion chamber? I'm not hearing anything unusual - wish I had one of those "pen light cameras" to look in there.

Bent valve is sounding more likely. Or maybe a bent rocker arm. Maybe I could check that out.

On this video - at 4:29, this is the position my decompressor is in for my cam pulley. And clearly, this motor has clearance on the exhaust valve.

Doing a valve job (and potentially engine rebuild) is beyond my capability. I was willing to tackle changing the cam pulley, but that's about my limit, I think.

Disappointing - pressure washer was only a couple years old....

Click to expand...

The Honda engine has a two year warranty. If it is still under 2 years (or very near it), you can get it warrantied.

hppants: I foresee a GCV160 tear-down and rebuild in your future.

Spent some time with it yesterday. Turns out that the "zero clearance" issue I thought I had with the exhaust valve was really just me not having the piston at TDC and ensuring that the cam marks were lined up. When I did that, what I really had on the exhaust was HUGE clearance - like well over 0.040"!! I was able to adjust that, and while in there, I adjusted the intake just a smidge (it was only about 0.002" loose). Made no difference. No compression and no start (squirt of carb spray or otherwise). I don't think the excess exhaust clearance is affecting my issue - I might have a bad rocker, but the valve should still close and provide compression - right?

I pulled the gas tank and the "starter engager thingie" above the flywheel and confirmed that the key is in the keyway.

I also can now see how the decompressor mechanism works for on the cam pulley (ingenious) and that isn't bad.

I can push in both valves and they appear to move freely, but of course who knows if the valve is bent - I didn't do a leak down test.

So I suppose I'm down to either a bent valve, broken piston ring, or ....??????.

think it's beyond my ability now - first time I've ever had a honda motor (of any kind - car, SUV, small engine, etc.) fail.

Bent valve would be very unlikely. If they get bent, they don't move. Broken piston and or ring...quite rare at best. Can you confirm that the piston is actually moving with the crankshaft? Since this is an overhead cam engine and the cam is connected to the crankshaft via a belt, it's likely that the connecting rod broke. If it pulls over super easy, broken rod. Doubt it would be worth repairing even if you were able.

I have a Honda gcv160 on a 4 year old pressure washer. Was using it yesterday, ran out of gas, filled it back up and now it will not start. I’m not an excellent mechanic to say the least. But I do know a little bit. I had no compression in the cylinder. I pulled the valve cover and found that the exhaust rocker arm has quite a bit of play in it. Upon further inspection the valve doesn’t have the range of movement that the intake valve has. So I used a borescope and was able to verify that the exhaust valve is not closing all the way. Which would explain the no compression. I inspected the piston and there are no marks on it indicating the piston made contact with the valve. So my question is. What could cause it to be running fine, run out of gas and bend a valve? My next question, is it worth fixing? I’ve never tore a small engine apart before but think I can do it. But I’m not going to fool with it if anyone thinks the head might be damaged as well.

WickedV 77 said:

I have a Honda gcv160 on a 4 year old pressure washer. Was using it yesterday, ran out of gas, filled it back up and now it will not start. I’m not an excellent mechanic to say the least. But I do know a little bit. I had no compression in the cylinder. I pulled the valve cover and found that the exhaust rocker arm has quite a bit of play in it. Upon further inspection the valve doesn’t have the range of movement that the intake valve has. So I used a borescope and was able to verify that the exhaust valve is not closing all the way. Which would explain the no compression. I inspected the piston and there are no marks on it indicating the piston made contact with the valve. So my question is. What could cause it to be running fine, run out of gas and bend a valve? My next question, is it worth fixing? I’ve never tore a small engine apart before but think I can do it. But I’m not going to fool with it if anyone thinks the head might be damaged as well.

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Did you take care of the GCV160? Meaning routine maintenance? If you do not know what you are doing, send the GCV160 to me and I will have a look at it.

Chris Parman said:

Did you take care of the GCV160? Meaning routine maintenance? If you do not know what you are doing, send the GCV160 to me and I will have a look at it.

Click to expand...

I checked the oil in it before I used it. Other than that there’s really no maintenance. Where are you located? Unless you are local to me pretty sure I could buy a new pressure washer cheaper than I could ship this one somewhere.

WickedV 77 said:

I checked the oil in it before I used it. Other than that there’s really no maintenance. Where are you located? Unless you are local to me pretty sure I could buy a new pressure washer cheaper than I could ship this one somewhere.

Click to expand...

I'm in Texas

WickedV 77 said:

I have a Honda gcv160 on a 4 year old pressure washer. Was using it yesterday, ran out of gas, filled it back up and now it will not start. I’m not an excellent mechanic to say the least. But I do know a little bit. I had no compression in the cylinder. I pulled the valve cover and found that the exhaust rocker arm has quite a bit of play in it. Upon further inspection the valve doesn’t have the range of movement that the intake valve has. So I used a borescope and was able to verify that the exhaust valve is not closing all the way. Which would explain the no compression. I inspected the piston and there are no marks on it indicating the piston made contact with the valve. So my question is. What could cause it to be running fine, run out of gas and bend a valve? My next question, is it worth fixing? I’ve never tore a small engine apart before but think I can do it. But I’m not going to fool with it if anyone thinks the head might be damaged as well.

Click to expand...

As the engine runs out of fuel it will start to run lean
lean running = overheating
Overheating causes the exhaust valve to expand & get stuck in the guide.

This is interesting. Every time I used my pressure washer, I ran the fuel out of the carb in an effort to limit the possibility of gunking it up during the long periods between use.

Maybe I did it to myself.

Well you are doing exactly what I advise all my customers to do and what I do myself.
Never turn an engine off with the key unless I have not quite finished with it.
You are there & I am here so I can not see it but it does not take much of a build up on the fins to cause the engine to overheat.
Running a lottle slow will also caus them to overheat as the air flow is a log function of the speed, not linear.
So an engine running a little slow & a little lean with a little dirt on the fins or fan or part of the blower housing loose or damaged or a bit low on oil or a combination of any of these and you can get overheating.
people mix up good operating practice for water cooled engines when a cool down slow run before shut down is good and air cooled engines where shut down should be done at full speed.

Another valve adjustment method.
1.Turn motor over in the PROPER running direction till one valve is fully depressed down. Adjust the opposite UP valve per recommended specs.
2.Rotate motor till the other valve gets depressed. Adjust opposite valve to proper spec.
3.Drink a cold one.

Lots of people get confused on TDC and what stroke. The above method takes out the guesswork. BTW, some manuals say TDC, then rotate till piston is 1/4" into the bore. Check YOUR manual for best info.

slomo

Cracking open & repairing a GCV engine is not that hard & is actually fun. Here is the first of a complete series on how to do it. If you don't have some of the tools, Autozone, etc. has loaners. That's where I got the ring compressor when I did it.

JBtoro said:

Cracking open & repairing a GCV engine is not that hard & is actually fun. Here is the first of a complete series on how to do it. If you don't have some of the tools, Autozone, etc. has loaners. That's where I got the ring compressor when I did it.

Click to expand...

This gentleman's video's on the GCV series engines are very detailed and precise. These videos (upwards of 30 videos) are a must for anyone. I learned a lot from these videos.