1997 200 Ocean Pro

"The motor has a ton of hours

"The motor has a ton of hours on it but the compression is reasonable and it runs fairly well but needs some work. At first it wouldn’t idle below 1000 rpm and rebuilding the carbs helped but the idle still isn’t as steady as I believe it should be. Perhaps it’s normal but my old 175 hp Black Max would just sit at idle all day long and drone you to sleep and this motor just doesn’t do that.

I took it out the other day and brought it up on plane and ran about 5 miles out when I heard what I could best describe was the sound of the lower unit momentarily dropping out of gear. There way no audible change in the rhythm of the motor, just a sudden shutter like I hit something. I stopped and raised the motor to make sure it wasn’t the prop but found nothing and took off again. I ran remaining 10 miles without further incidence. Left to head back home and it happened once about a mile out but the remaining 14 miles where without incidence.

I checked the LU linkage when I got back and found nothing wrong so I’m now looking at the possibly that a cylinder was dropping out causing the noise. I checked the plugs and they actually looked pretty good. I ran it on the hose at home and it seems to start an intermittent miss at higher rpm 2000 – 2200 rpm (although not noticeable while running in the water) and sends out a cloud of smoke when you first dump the throttle. The smoke clears in a matter of seconds but clears up in a matter of seconds and smokes no more than usual after that.

Compressions is a little low (100 – 105) but constant across all cylinders. I’m giving it one more try it’s off to the pros to diagnosis."

Can You post a photo of Your s

Can You post a photo of Your spark plugs?

The plugs have roughly 30 hour

The plugs have roughly 30 hours on them and generally look like new except the surface has taken on that heated/metallic brown color. They all had a very light fuel/oil coating but plugs #1 and #3 had slight traces of carbon flakes around the rim also. Insulators where split almost right down the electrode with one side being a nice cream color and the other side a dark brown color

I'll take picture and post tomorrow.

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" plugs

"They does not look quite the

"They does not look quite the way I would like. First what is the plug spec? (should be Champion QL78YC)
Secondly I suspect Your engine to be overoiling which normally is caused by a leaking fuelmembrane or valves in the pump housing. The pump gives a certain amount of oil at every pump stroke which is mixed with the fuel in the fuel section of the pump. If the pump draws less fuel on each stroke than intended, the oil mix would be too rich. I think a check of the VRO would be in place.
Your engine may be rather carboned up in the exhaust area, give it a good run with 'engine tuner' (OMC) or similar product to clean it out."

NB: Sorry about the plug spec:

NB: Sorry about the plug spec: QL77JC4 is the recomended ones. Mistook Your engine for a 60 degree.

Thanks for the information.

Thanks for the information.
I keep a new VRO onboard as a spare so I'll swap itout the VRO and rebuild the old one for my spare. The plugs are QL77JC4 so I'm good there.


BTW: Did they make a design change in the gasket matl to accommodate ethanol? I ordered 6 carb kits and some had black gaskets and others a brown gasket.

I had 3 needle valves go the same day I first filled the tank with E10 so I’m left wondering if it’s was a compatibility issue. I have a 10 um filter on the system and the carbs where clean at tear down so now I wonder about the black gaskets in the carbs.

"The old ones used to be '

"The old ones used to be 'black' and the resistant ones 'brown' But a lot of things happened during the 'bankrupcy' priode and parts were obviously taken a bit from here and there! I have even seen aftermarket (non OEM) parts 'black', but oviously alchohol resistant. As for the needle tips, the old ones was as far as I remember red and then turned black, but even there quite a mess. (unused grey, but only a protecting grafit powder for storage)."

"OK, I swapped out the VRO and

"OK, I swapped out the VRO and replaced all the vacuum and fuel hoses back the bulb while I was at it. I’ve oil primed the VRO and will start the motor from a can of premix but how long will I need to run the motor on premix before changing back over to the on-board fuel tanks? Some have suggested that I mix my onboard fuel supply but I have 85 gallons or so of fuel onboard and I don’t particularly want to mix that much fuel if I can help it.

BTW: The old VRO appears to have psat the test but I installed the rebuilt one for good luck. If this isn't it anymore ideas? Will a kinked oil hose cuase a similar problem?"

"When sttarting, do a test on

"When sttarting, do a test on the alarm system at the same time. Start with a 2% mix in a separate tank and pull off the oil hose close to the pump. The alarm should go on. Put the hose back and the alarm will go off (when the VRO takes oil). If this works, You may straight away go back to the original set up. It might be smart to put a piece of tape or mark at the oil tank and monitor the oil consumption. In general the engine should take around 2% oil in average.
A kinked oil line would normally result in less oil/ fouling of plugs, but it would need almost to be completely 'blocked' for that to happend."