Extremely helpful. Just changed my head gasket and wondered why I had a small piece of metal leftover. After watching this video I learnt it’s my exhaust valve turner!!! Pre head gasket it was running fine just smoking real bad. Now it runs, no smoking and cuts out- going to put the valve rotator on and refit the carb so I’ll have to post an update. Thanks man
@@autotech4103 I still have the smoking issue after a new head gasket. The valves aren’t leaking and the cylinder isn’t scored. The oil inside looks fairly new so I’m wondering if the previous owner used the wrong oil. It starts up fine and dies after 30 seconds- if I remove the oil sensor it will keep on running. Your help is appreciated man!
After running the engine for a while I can now see black oil coming out of the rocker cover on the exhaust side and oil coming out where the exhaust bolts on
Thank you so much for the detailed explanation... but I have noticed that the exhaust valve has a spring seat it's like a washer whereas the intake valve spring doesn't have one...is it necessary to buy one and install it under the intake spring valve or not necessary... My regards...
@@autotech4103 yes I know about the retainer but I meant the piece that sits underneath the valve spring which seems like some sort of spacer between the spring and the cylinder lead itself
I have a 390 that had a stuck valve. I took the head off like you have here. Disassembled it. Got un stuck. Put it all back together. Now I can see the valves moving fine with the cover off. But when I put the spark plug back in I can’t pull the recoil starter. I did set the lash clearance at .006 and .008 before. So any idea why the recoil won’t turn only when the park plug is in?
The decompression lever on the camshaft could be faulty. Also the valves need to be set with the piston at TDC of the compression stroke. If it was set in any other position, that could cause it as well
hi awesome videos that you do nice ,easy to follow instructions ,im having problems with my 25 yrs old countax tractor mower with a honda GXV390/GJAA 13 HP engine ,its turning over but will not fire up ,there is spark ,fuel getting through ok,set lash on valves but still no joy ,took cylinder apart after your video ,checked valves fine making that poping sound ,poured petrol over valves to test for air leaks ,no leaks but noticed that on intake valve side that the valve guide sits higher than the valve guide on exhaust side is this normal for these engines if so my next step is to check the compression release on camshaft incase it has failed ( also noticed i have seals on end off both valve guides ) any help would be really appreciated kind regards GOOD WORK !!!
I would test compression. If you don’t have a compression gauge you can always just block the spark plug hole with your finger and pull the rope. Pressure should force your finger off the hole
@@autotech4103 thanks for your speedy responce,the issue with valve guides, that one being higher than the other concerns me,has the seal sits so high it looks like it has no purpose.its so hard to get any info on this engine in uk they all just want to sell you parts ,i can forward pics if you got a public email address. cheers Autotechcp ( or should i be calling you Mr. Henderson now)
@@jazzsingh263 I have seen a valve guide slide out of the head like that. You can drive it back into place with a deep socket and a hammer. It may just slide out again or it may stay put. Worth a try…….
@@autotech4103 The point is MR Henderson ,im not to sure if it is designed that way before i go tapping it down, it was working perfectly turned off for 5 mins then wouldnt start again, thank you for your time
So what is the fix if the "suction" isn't the same on both intake and exhaust? I don't see any seal listed or guides listed on parts diagrams for my GX340 k1 engine (older 11hp) I get some suction, just not nearly as much as on the intake. BTW, love your videos!!
First off make sure the valve and guide are both clean. Then I would measure the valve stem in multiple spots and compare that to spec. You will need a micrometer for that. There is a procedure called “knurling” which can make the guide hole “tighter”. I don’t have the tools for knurling and would need to send it away to a machine shop. They could also drill out your guide and press in a new one.
... I watched this WHOLE video JUST to see how to install the valve rotator and THATs where you cut it off!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!???????????????????????????
The rest of the video library is here. Honda Engines th-cam.com/play/PL7CHuGTmbkh0yCS3FT1QyWs6pM4bwC5C9.html Hope you find what you need. If not, there is a complete engine assembly video you can scroll.
Extremely helpful. Just changed my head gasket and wondered why I had a small piece of metal leftover. After watching this video I learnt it’s my exhaust valve turner!!! Pre head gasket it was running fine just smoking real bad. Now it runs, no smoking and cuts out- going to put the valve rotator on and refit the carb so I’ll have to post an update. Thanks man
If it still has problems go ahead and post any questions. Hope we can help
@@autotech4103 I still have the smoking issue after a new head gasket. The valves aren’t leaking and the cylinder isn’t scored. The oil inside looks fairly new so I’m wondering if the previous owner used the wrong oil. It starts up fine and dies after 30 seconds- if I remove the oil sensor it will keep on running. Your help is appreciated man!
After running the engine for a while I can now see black oil coming out of the rocker cover on the exhaust side and oil coming out where the exhaust bolts on
Thank you for doing this it is a great help to me.
It feels good to get comments like this. Right On!!
Great job and information is wonderful 😊😊❤😊😊
Thank You 🙏
Happy rebuilding!!!!
Thank you so much for the detailed explanation... but I have noticed that the exhaust valve has a spring seat it's like a washer whereas the intake valve spring doesn't have one...is it necessary to buy one and install it under the intake spring valve or not necessary...
My regards...
That cap on top of the valve retainer of the exhaust valve is a rotator. The intake side doesn’t have one.
@@autotech4103 yes I know about the retainer but I meant the piece that sits underneath the valve spring which seems like some sort of spacer between the spring and the cylinder lead itself
@@aymannabil9 that retainer washer is only on the exhaust valve. I have checked the Service Information to make sure.
@@autotech4103 ok I got you👍 thank you so much ...now I'm gonna install the valves and continue assembling my generator
My regards to you👍
I have a 390 that had a stuck valve. I took the head off like you have here. Disassembled it. Got un stuck. Put it all back together. Now I can see the valves moving fine with the cover off. But when I put the spark plug back in I can’t pull the recoil starter. I did set the lash clearance at .006 and .008 before. So any idea why the recoil won’t turn only when the park plug is in?
The decompression lever on the camshaft could be faulty. Also the valves need to be set with the piston at TDC of the compression stroke. If it was set in any other position, that could cause it as well
@ thanks. I will look into the decompression lever. Need to find videos on that.
@@autotech4103 I wonder if it’s the decompression release lever if it would be under Honda’s Warranty. It’s not a very old machine.
@ they have grounds to deny you if it’s been put together incorrectly. It’s worth a go….
hi awesome videos that you do nice ,easy to follow instructions ,im having problems with my 25 yrs old countax tractor mower with a honda GXV390/GJAA 13 HP engine ,its turning over but will not fire up ,there is spark ,fuel getting through ok,set lash on valves but still no joy ,took cylinder apart after your video ,checked valves fine making that poping sound ,poured petrol over valves to test for air leaks ,no leaks but noticed that on intake valve side that the valve guide sits higher than the valve guide on exhaust side is this normal for these engines if so my next step is to check the compression release on camshaft incase it has failed ( also noticed i have seals on end off both valve guides ) any help would be really appreciated
kind regards
GOOD WORK !!!
I would test compression. If you don’t have a compression gauge you can always just block the spark plug hole with your finger and pull the rope. Pressure should force your finger off the hole
@@autotech4103 thanks for your speedy responce,the issue with valve guides, that one being higher than the other concerns me,has the seal sits so high it looks like it has no purpose.its so hard to get any info on this engine in uk they all just want to sell you parts ,i can forward pics if you got a public email address.
cheers Autotechcp
( or should i be calling you Mr. Henderson now)
@@jazzsingh263 I have seen a valve guide slide out of the head like that. You can drive it back into place with a deep socket and a hammer. It may just slide out again or it may stay put. Worth a try…….
@@autotech4103 The point is MR Henderson ,im not to sure if it is designed that way before i go tapping it down, it was working perfectly turned off for 5 mins then wouldnt start again, thank you for your time
So what is the fix if the "suction" isn't the same on both intake and exhaust? I don't see any seal listed or guides listed on parts diagrams for my GX340 k1 engine (older 11hp) I get some suction, just not nearly as much as on the intake. BTW, love your videos!!
First off make sure the valve and guide are both clean. Then I would measure the valve stem in multiple spots and compare that to spec. You will need a micrometer for that. There is a procedure called “knurling” which can make the guide hole “tighter”. I don’t have the tools for knurling and would need to send it away to a machine shop. They could also drill out your guide and press in a new one.
Sir is it ok if i put two stem seal?
Yes. Not necessary but should be ok. As long as the valve opens and closes properly.
Thank you sir❤
... I watched this WHOLE video JUST to see how to install the valve rotator and THATs where you cut it off!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!???????????????????????????
The rest of the video library is here. Honda Engines
th-cam.com/play/PL7CHuGTmbkh0yCS3FT1QyWs6pM4bwC5C9.html
Hope you find what you need. If not, there is a complete engine assembly video you can scroll.