Seized Honda GX 390

[Red Horse]

Well I took recoil off so for sure I'm looking at the "notch" that is supposed to be TDC when it is 90 degrees from horizontal. I also have a small screwdriver that is resting on piston and that confirms piston is at TDC. If both valves are tight against rocker arms, that tells me I'm at TDC at end of "compression, start of power". Rotate 360 and I'm back to TDC with both valves "slack" as I'm at end of "exhaust stroke and start of intake". this is point at which I'm setting valves.

All of the "experts" on You Tube, show valve adjustment taking place when both valves are slack.

I did this late this afternoon and turned it over two or three complete cycles and it held adjustment.

We on same page?

 

[tomplum]

This works for me. Slowly cranking the engine, return the engine to TDC just after the intake valve closes. Use a dowel or a safe screwdriver to determine the end of the piston travel. Then set the lash.

 

[jaydee325]

Well I took recoil off so for sure I'm looking at the "notch" that is supposed to be TDC when it is 90 degrees from horizontal. I also have a small screwdriver that is resting on piston and that confirms piston is at TDC. If both valves are tight against rocker arms, that tells me I'm at TDC at end of "compression, start of power". Rotate 360 and I'm back to TDC with both valves "slack" as I'm at end of "exhaust stroke and start of intake". this is point at which I'm setting valves.

All of the "experts" on You Tube, show valve adjustment taking place when both valves are slack.

I did this late this afternoon and turned it over two or three complete cycles and it held adjustment.

We on same page?

You sound 360 degrees out.

At TDC of the exhaust stroke, the valves/rockers/pushrods will "rock" (exhaust valve closes, intake opens). You would rotate 360 degrees from there and be at TDC of compression. You set the valves at TDC of compression stroke.

 

[Red Horse]

I think we are on same page and I "mis-spoke". When you are at TDC and rockers are slack, that to me is both valves are closed-springs are keeping them down- and it is about to fire-the power stroke-then next stroke up is exhaust and you are again at TDC then intake opens on down stroke pulling in new charge then back to TDC on compression stroke with both valves closed at TDC just prior to ignition.

 

[tomplum]

Are you up and running now?

 

[Red Horse]

Tom, Jaydee,
YES! finally. Once I got everything back on, started on 2nd pull. You saw the picture of the crud that was in that motor. I don't know how that could happen. Even if it was left outside all the time how would water get in it?

Didn't spend a lot of time today after I got it running so I'll install the blower tomorrow and see how it does under load.

By the way a lot of good info on You Tube. Also some stuff that makes no sense-"Let the buyer Beware"

One guy though that usual nails it is "Steve's Small Engines"

thx everyone for your comments.

 

[goeduck]

GOOD JOB Staying with it !! I have a GX 390, never an issue with it.

 

[Red Horse]

guys update! Have probably used it about two hours now blowing leaves. My friend told me I "might" be able to clean up head without damaging rings cautioned against forcing piston travel as that would in fact damage rings. I guess I was lucky as it doesn't smoke and doesn't use oil-at least so far. Starts by the way on first or second pull-although a couple of times it has fired right up then died. After a couple of tries it stays running with good power.

Next project is I've got a plan so I can "clip it" to left front of Bucket on my 4720. I'm too old and this sucker is too heavy to push up my driveway-stay tuned-and again thx for all your opinions

 

[aczlan]

Interested in seeing what you work out, mounted a similar mower to the front of a golf cart that had a 2" receiver on the front using a piece of 2" box tubing with a notch cut out of one side and a couple pins that went through to lock it in, then a strap to secure the handle and keep it from tilting down (so the front wheel stayed in the air).

Aaron Z