Worn Piston Ring on my Merc 4.3l TKS

[fishrdan]

Re: Worn Piston Ring on my Merc 4.3l TKS

One of the plastic standoffs from my flame arrestor had broken off and lodged itself in one of the barrels.

With finding that plastic part wedged along side the venturi, I'd definitely think that could have caused a lean condition. Disrupted air flow and a lack of fuel pulled through that section of the venturi. How does the location of that obstruction correlate to cyl 3, or, is cyl 3's intake port aligned with the obstruction.

BTW, those MerCarb's are pretty easy to rebuild, just make sure it's completely torn down and soak it in a bucket of carb cleaner, rinse well in hot water and blow it out good. I hit all the passages with spray carb cleaner also, just to make sure everything is clean. Before tearing it apart, lightly seat the idle mixture and idle speed screws, counting the turns it takes to lightly seat the screws. (draw a little picture of where the screw heads are clocked) This will give you a base line setting for getting the carb dialed in again.

Did you have your engine rebuilt yet?

 

[jdwarns]

Re: Worn Piston Ring on my Merc 4.3l TKS

Thanks for the reply, fishrdan.

How does the location of that obstruction correlate to cyl 3, or, is cyl 3's intake port aligned with the obstruction.

The obstruction was on the same side as cyl 3's intake port.
The obstruction was blocking the air passage but not the fuel from the nozzle, which would initially lead me to believe that this would cause a rich condition, however, airflow dynamics are complicated and it's difficult to predict with certainty the impact of altering the normal turbulence.

BTW, those MerCarb's are pretty easy to rebuild, just make sure it's completely torn down and soak it in a bucket of carb cleaner, rinse well in hot water and blow it out good. I hit all the passages with spray carb cleaner also, just to make sure everything is clean. Before tearing it apart, lightly seat the idle mixture and idle speed screws, counting the turns it takes to lightly seat the screws. (draw a little picture of where the screw heads are clocked) This will give you a base line setting for getting the carb dialed in again.

Good stuff... thanks for the advice.

Did you have your engine rebuilt yet?

Carolina Machine Engines turned my engine around for me in two weeks. I'm extremely impressed with the operation they're running. They even included a Fel-Pro gasket set for completing the reassemble. The intake manifold gasket set is the only one I decided to buy separately since the one included in the kit had the passage between the single port and side-by-side ports closed off with metal. From what I understand, I need this passage to be open for my TKS to automatically choke the carb properly. I imagine I could have cut the metal out, but I don't like the idea of altering a gasket. I was tempted to get the gasket set at Michigan Motorz for $35, but decided that this gasket set is important enough to spend the $80 on Quicksilver.