Honda 5.5hp GCV160 possible valve or piston ring issue?

[arch252]

I have a Honda GCV160, GJAEA-3313087 mounted on a pressure washer. I picked it up in non-running condition with little history about it. When I got it there was an obvious major oil leak coming from the valve cover. This is the first engine like this I have worked on. I was quite surprised to find there was no head gasket and the case splits in an odd diagonal direction. I learned the hard way about keeping the valves in place before you remove the crankshaft. They slipped out and I had quite the time removing the crankshaft.

I removed the valve cover to expose the rockers and the plastic timing gear and timing belt. There was a significant amount of oil in the valve cover, far more than I have seen before and more than I expected to see, but not having worked on this type of engine before I didn't know if that was normal. I removed the valve keepers and springs. I removed the valve stem seal from the intake valve. There was not a stem seal on the exhaust valve. It was obvious that a lot of oil had been passing through the exhaust valve stem opening, there was burnt oil residue build up on the retainer side (valve cover side) of the exhaust valve stem opening.

It doesn't seem right to me that there should be that much oil passing by the piston and being pushed out through the exhaust valve. The burnt oil residue seemed to indicate to me that the oil was being pushed through at extremely high pressure by the piston, causing the oil to burn.

Based on this can anyone identify what the problem might be. Are the piston rings bad and allowing excessive oil to pass? The cylinder looked just fine, no scoring at all. There were no metal shavings or anything out of place in the crankcase. I don't see anything obvious.

If the rings are the culprit and I replace the rings, is it likely that any permanent damage has been done?

Has anyone run into this before? Needing some guidance. Thanks

Rick

 

[mechanic mark]

OEM Parts : CyclePartsNation Honda Parts Nation great source for Honda parts, I would purchase a service repair manual for your engine. You need to inspect everything visually for wear, rod bearings, etc. Manual will give you the information you need to do the job right the first time, yes it sounds like your piston rings are worn out.

Amazon.com: Honda GCV135 GCV160 GCV190 GSV190 Engine Service Repair Shop Manual: Patio, Lawn & Garden

Honda GCV135 GCV160 GCV190 GSV190 Engine Service Repair Manual Slight Damage | eBay

Make sure you get all numbers from your GCV160 so you get correct rings, head gasket, etc. Adjust valves last with engine cold.

 

[arch252]

Thanks Mark, I really don't want to buy a manual, heck I only gave $30 for the entire pressure washer and the pump is good so I don't want to spend any more money on this engine than I absolutely have to. I was really just hoping that with all the experience here someone would say that they have run into this problem or they recognize this problem and what I need to check is....

 

[bertsmobile1]

It can be bad rings or bad breather.
They vent through the rocker cover so I expect to find a bit of oil there.
The exhaust valve runs near to yellow hot on modern engines so some oil that gets on the stem will burn.
A lot of build up is generally a sign of worn valve guide.

There is no magic wand to wave over your engine.
If the bore is OK and not excessively worn or ovalled then you might get away with a set of std rings, a valve guide and a gasket set.
Don't expect to get out of this for under $ 100 plus your labour.
As previously stated, do it once, do it right and forget about it for the next 15 years.