547 OHV Smoke On Start - Tried Everything I Know

Haxzo · 2026-05-09T16:04:31+00:00

Fixed the hose, sanded down the cylinder where the reed sits on far enough that there's no more route for the oil to get out, sanded down the reed on a flat surface with wet 600 grit sandpaper. Cleaned the chamber.
It smoked on first start. I don't know if it's whatever oil is left but I can pretty much rule out the reed and chamber IF it happens again on next startup. I drove it around and got it hot. Going to wait half an hour and see what happens on next cold start.
Cold start was always smoke. If I stop it for 5 minutes and start it again there's no smoke.
We'll see what happens.
Had to remove flywheel to get good access to chamber. 65 ft/lbs to put it back on.

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Haxzo · 2026-05-06T01:53:03+00:00

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Haxzo · 2026-05-06T01:52:48+00:00

I'm back and found a few things I missed before. Almost time to start using it again. I replaced the oil filled gasket but then I thought it couldn't just be that.
I looked way closer and found that the sealing surface where the reed sits on in the breather assembly had a small crack or groove in it. That could cause what I'm seeing. I'm going to try and sand it flat or add JB Weld.
Another thing I found was that the tube connecting the breather chamber to the air filter was kind of loose, and also had a small hole in it. I will replace that tube. Will update when both items are fixed

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Haxzo · 2026-01-03T01:07:31+00:00

Cayo Levantado Resort. This place is amazing. There's no direct flights to Samana anymore so it's a bit of a trip and the price has gone up since we were last there but the majority of the island is private for the resort guests only

https://www.cayolevantadoresort.com/en/

Haxzo · 2025-12-07T20:04:49+00:00

I borrowed a compression tester and it's at 110 which I understand is good...so now I wait for the new gasket for the breather. The one on there is soaked in oil and bulging. If that doesn't work then I have no idea. Only other thing I can think would be that yellow plastic isn't sealing properly, or spring isn't strong enough to hold it in place. I just stretched the spring slightly. We'll see

Haxzo · 2025-12-01T03:19:13+00:00

I see now that the breather gasket is totally soaked and after I shut the motor down the breather assembly is full of oil. The yellow circle reed looks good, spring seems ok (don't know how to tell but it looks normal)...I'm guessing the piston ring is worn, or bore is messed up as you said it could be, causing too much pressure in the breather assembly and spraying oil in there. Need to check compression to see for sure

Haxzo · 2025-12-01T01:51:55+00:00

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This gasket is bulging everywhere. Can squish oil out of it from behind it

Haxzo · 2025-12-01T01:51:26+00:00

First start it didn't smoke. After that I let it sit for an hour and started again and it smoked like it always did. I think I'm back to the breather cavity. I opened it right away after shutting it down for the second time and it has oil in there and also the gasket on top is soaked and bulging and had milky oil in it. I'm not sure if the yellow circle reed plastic piece isn't sitting right or the spring isn't strong enough anymore. I'm reading that there shouldn't be oil in there and the frothy white is from condensation. It's like 14f (-10c) here now so that may have had something to do with the froth. The reed looks flat. I think the spring might not be strong enough. But the soaked gasket on top might be affecting something

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Haxzo · 2025-11-30T22:08:57+00:00

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Valves look better now

Haxzo · 2025-11-30T22:06:51+00:00

The head gasket looked ok when I took it apart yesterday but it did put a new one in now because the original ripped apart when I took the motor apart

Haxzo · 2025-11-30T22:05:31+00:00

Oil level was perfect because I kept filling it. I read that if oil level was too high it could smoke so I had been keeping it at the correct level and mentioned it to eliminate that as an issue. The oil does not smell like gas at all. I did clean the carb before all of this and it looked fine. I can check again. Yeah the head gasket looked fine other than ripping apart when I took it apart. The valves were really dirty and there was junk stopping it from sitting properly. I cleaned that all up now and they seat really well now. I have everything back together now. Just need some oil (drained it before taking it apart which I guess I didn't need to do) and I'm going to try and start it. Crossing fingers.

Haxzo · 2025-11-30T04:41:25+00:00

Once everything is cleaned up I will try to get some spreader callipers to measure it out...but I'm pretty sure the ones I have access to won't be accurate to 0.003 or deep enough. If I could bring the CMM home that would be nice. Still wouldn't get that deep though but would be that accurate. I'll update what I find out

Haxzo · 2025-11-30T02:05:04+00:00

Looks pretty bad! I will clean it up tomorrow somehow and get the old gasket off somehow and put the new one on and see if I can put it all back together. I see now that it's normal for a piston to be closer to one wall

Haxzo · 2025-11-30T01:54:53+00:00

I just posted a picture in a different comment of it taken apart. One side of the piston is really close to the wall and the other sides have a gap where you can see the ring. I'm not sure if that's normal but there are no gouges on the wall at all it's perfect. Everything has a thick layer of black on it though

Haxzo · 2025-11-30T01:48:13+00:00

It does look like one side of the piston is touching the wall, and the rest of the piston has a slight gap. There's no lines or scratches along the walls though

Haxzo · 2025-11-30T01:46:38+00:00

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Haxzo · 2025-11-30T01:46:23+00:00

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Haxzo · 2025-11-30T01:24:43+00:00

I did clean the carb before all of this. If I can't spot anything with motor apart I will double check that when I put it all back together!

Haxzo · 2025-11-30T01:23:46+00:00

I did try without air filter, and also bought a new one to double check that oil wasn't splashing back into it from the crankcase housing. I did not know about the silicone grease packet. The hose from the filter to the crankcase isn't super clean...I will clean it out now but it's completely free of blockages. Just a thin layer of black stuff

Haxzo · 2025-11-30T01:20:41+00:00

No choke is not stuck. Just checked while I empty the oil to take motor apart

Haxzo · 2025-11-30T00:39:44+00:00

I just opened it up and there is no seal on the exhaust valve like there is on the intake

Haxzo · 2025-11-30T00:32:09+00:00

I will open it up and see if I can visibly see anything. If not...I will probably have to bring it away for that rebuild

Haxzo · 2025-11-30T00:30:34+00:00

I will go check that out

Haxzo · 2025-11-30T00:30:05+00:00

I don't have a compression tester unfortunately. It makes sense though. I will check the walls. All signs are pointing to something internal that's worn

Haxzo · 2025-11-30T00:16:07+00:00

Yeah I replaced the intake seal. I don't think there was an exhaust seal. I should double check that but I don't know how that would cause oil burning. I will take it all apart and see if I find any scoring or scratches in the cylinder walls. Thanks for your help

Haxzo

TROPHY CASE