Moto 225 blue cloud of smoke

[Brad1968]

I purchased a '87 Moto 225. It didn't run. After getting it running, I was surprised it smoked like a smoke stack because it was rather quick. I'm guessing it's the head gasket. 

Has anyone had a smoking problem? 

[Gwbarm]

If its been sitting for a while the rings may be stuck, it may come around a little the more you run it but if its smoking as much as you say its provbably a badly worn engine. Is it smoking from around the head.

[Mech]

If the smoke's coming out the exhaust it might settle down after a run or two, or it may need rings and/or valve guide seals. You should check the oil isn't overfull, and that the breathers are clear and working.

If the smoke's rising off the outside of the engine it may have an oil leak, or just need a clean.

[Brad1968]

On 8/11/2024 at 7:54 PM, Gwbarm said:

If its been sitting for a while the rings may be stuck, it may come around a little the more you run it but if its smoking as much as you say its provbably a badly worn engine. Is it smoking from around the head.

I though about the rings, but it has a lot of power. It could be the oil ring. I'll do a pressure leak down test again. It's smoking from the tail pipe.

On 8/12/2024 at 12:50 AM, Mech said:

If the smoke's coming out the exhaust it might settle down after a run or two, or it may need rings and/or valve guide seals. You should check the oil isn't overfull, and that the breathers are clear and working.

If the smoke's rising off the outside of the engine it may have an oil leak, or just need a clean.

I did notice oil squirting out around the dip stick & then pulled the vent tube off & it quit. It's still smoking. I'll keep an eye on the level and see if the smoking starts to subside. It takes about 5 seconds before it starts to smoke.

[Mech]

The vent tube needs to be clear or the crankcases pressurise which can cause oil leaks and even blown out oil seals, and it can make them smoke. That tube is probably full of oily crud. Clean it out and it will be like a new bike .. haha.

[Brad1968]

More than likely it is plugged by a mud robber.

I bought an overhaul kit (piston, rings, jug etc) and I'm going to make time to overhaul it soon.

[Gwbarm]

That sounds like a ggod plan, 

[MagnoliaHunter]

when does it smoke? on startup?  after it gets warm? or all the time?

[Brad1968]

On 8/20/2024 at 12:48 PM, MagnoliaHunter said:

when does it smoke? on startup?  after it gets warm? or all the time?

All the time.

[Gwbarm]

If its smoking that much it sounds like you may have a broken ring, im surprized it runs, have you checked the compression.

[Brad1968]

I pulled the head and jog off last Friday & Saturday. When I pulled the long head bolts, one of them was dripping oil. Does the 2 in most bolts serve a the oil ports?

The cylinder has not noticeable wear and the top of the piston and the head has very little carbon. I'm going to mic the piston to see if it is over sized.

[Gwbarm]

 It sounds like it may have been rebuilt recently.I would also check the piston ring end gap it should be between .0020 and .0024 thousands.

[Brad1968]

On 8/11/2024 at 7:54 PM, Gwbarm said:

If its been sitting for a while the rings may be stuck, it may come around a little the more you run it but if its smoking as much as you say its provbably a badly worn engine. Is it smoking from around the head.

I installed the new cylinder, piston & rings.  Runs great no smoke. I found a small rust spot in the cylinder. That was where the oil was getting by the rings. Thanks for your help.

[Gwbarm]

You have been busy glad it worked out, i suspected that was your problem.