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Oil gushing out of the exhaust ports

Benc65753
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Posts: 3
Joined: Mon Jul 10, 2006 1:15 pm

Oil gushing out of the exhaust ports

Post by Benc65753 » Mon Jul 10, 2006 3:31 pm

I coaxed my '68 CL77 back to life after 22 years of sitting in the barn. After getting it started, I observed raw oil gushing out of both exhaust ports. Thinking that I'd trashed my rings, I pulled the spark plugs expecting to see evidence of oil on them. They were clean and dry. I don't remember these 305's having valve stem seals. Do they? Does anyone have an idea where the oil might be coming from? I haven't removed the engine from the frame yet so I'm wondering if somehow the oil drain passages back to the sump became plugged. However, I don't have any oil coming out of the breather tube attached to the top coverplate. Is there anyone out there that might point me in a direction so I don't end up chasing dead-ends? Thanks.

Ben
Ben

LOUD MOUSE
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Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Re: Oil gushing out of the exhaust ports

Post by LOUD MOUSE » Tue Jul 11, 2006 7:07 am

How long did ya run the engine?
Any chance this is actually gas and is mixing with the carbon in the pipes?
If the plugs are not oily then the oil isn't comong through the combustion area. As the pipes are connected directly to the head at the exhaust port and the plugs are dry is it possable the OIL? may be just in the pipes and not coming out of the engine?
Heck I don't know!!!!!!!!!!!!!. ........lm
Benc65753 wrote:I coaxed my '68 CL77 back to life after 22 years of sitting in the barn. After getting it started, I observed raw oil gushing out of both exhaust ports. Thinking that I'd trashed my rings, I pulled the spark plugs expecting to see evidence of oil on them. They were clean and dry. I don't remember these 305's having valve stem seals. Do they? Does anyone have an idea where the oil might be coming from? I haven't removed the engine from the frame yet so I'm wondering if somehow the oil drain passages back to the sump became plugged. However, I don't have any oil coming out of the breather tube attached to the top coverplate. Is there anyone out there that might point me in a direction so I don't end up chasing dead-ends? Thanks.

Ben

Benc65753
honda305.com Member
Posts: 3
Joined: Mon Jul 10, 2006 1:15 pm

Re: Oil gushing out of the exhaust ports

Post by Benc65753 » Tue Jul 11, 2006 8:23 am

It gets wierder. I had put on the exhaust pipes because I'm afraid of the potential of exposing hot exhaust valves to ambient air, possibly warping them. (Something from my wayback past). After initially starting the bike, everything was fine. After running the bike around my pasture for ten to fifteen minutes, I noticed oil droplets being blown out the exhaust. I rode the bike back into the barn where I took out the plugs to look at them. Because they were clean I took off the exhaust pipes and restarted the engine. At this time I could see the oil dripping out of the exhaust ports. I didn't run the engine very much longer due to concerns of pumping the oil sump dry onto the floor. This problem runs counter to anything I've ever encountered with this 305 in the past. I'm stumped. I had it overhauled in 1973 and parked it due to being in the Navy. In 1984 I tried to start it but found the centrifical flyweights on the cam (spark advance) would stick in the advanced position. I got that straightened out and then had to park it again until just recently. The engine has less than 2 - 3 miles on it since overhaul but I suspect that I should probably disassemble it and inspect the engine from the cylinders up. I hesitate doing this because the gaskets are relatively new gaskets.
Ben

Hahnda
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Joined: Wed Nov 02, 2005 2:36 pm
Location: Cameron, WI

Post by Hahnda » Tue Jul 11, 2006 8:43 am

Was the bike smoking bad or just blowing oil?


I have a CA95 that smokes pretty bad but when I run a leakdown test I get pretty good numbers. Only about 5-6% leakage. When I do the test the valves are closed and pistons are TDC. My guess is that I am leaking oil past the guides.

Unlike you Ben I am getting oil into the combustion chamber so I assume my intake guides leak and your exhaust guides leak???????


Hey EMO, you have any thoughts on this???

LOUD MOUSE
honda305.com Member
Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Re: Oil gushing out of the exhaust ports

Post by LOUD MOUSE » Tue Jul 11, 2006 9:10 am

May I suggest you do remove the pipes and start the engine and get a better idea of what's what at the exhaust ports.
If you are concerned about warping the exhaust valves you can stuff a dry rag in the ports. ........lm
Benc65753 wrote:It gets wierder. I had put on the exhaust pipes because I'm afraid of the potential of exposing hot exhaust valves to ambient air, possibly warping them. (Something from my wayback past). After initially starting the bike, everything was fine. After running the bike around my pasture for ten to fifteen minutes, I noticed oil droplets being blown out the exhaust. I rode the bike back into the barn where I took out the plugs to look at them. Because they were clean I took off the exhaust pipes and restarted the engine. At this time I could see the oil dripping out of the exhaust ports. I didn't run the engine very much longer due to concerns of pumping the oil sump dry onto the floor. This problem runs counter to anything I've ever encountered with this 305 in the past. I'm stumped. I had it overhauled in 1973 and parked it due to being in the Navy. In 1984 I tried to start it but found the centrifical flyweights on the cam (spark advance) would stick in the advanced position. I got that straightened out and then had to park it again until just recently. The engine has less than 2 - 3 miles on it since overhaul but I suspect that I should probably disassemble it and inspect the engine from the cylinders up. I hesitate doing this because the gaskets are relatively new gaskets.

Benc65753
honda305.com Member
Posts: 3
Joined: Mon Jul 10, 2006 1:15 pm

Re: Oil gushing out of the exhaust ports

Post by Benc65753 » Wed Jul 12, 2006 7:21 am

With the pipes removed and with the engine started, I can see the oil dripping out of the exhaust ports. It's as if the oil is coming from the exhaust guide area or near there. The volume of oil worries me because I don't think it'd take long to drain the sump. As soon as I could stand the heat, rags got stuffed into the exhaust ports and are still there. The mud daubers around here are notorious for building nests in places you don't want them.
Ben

DieselsRcool
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Posts: 2
Joined: Mon Jul 03, 2006 2:24 pm
Location: Gig Harbor, WA. USA. Los Barriles, Baja Mexico

Post by DieselsRcool » Wed Jul 12, 2006 9:35 am

Pull the tappet caps and see if the oil is pooling above the valves. If so then you need to figure out why. Wrong head gasket? Mud dobber nest?

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