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Spark Plug Gap

DubsVA

New member
Hi all

Stupid question I know and I think I know the answer already but I wanted to see what people would think

I have a 2008 Tahoe with a Mercruiser Alpha One 4.3L TKS engine (6 cylinder). The engine book that came with the boat and the flame arrester sticker say the spark pulgs should be gapped at .060 in. A new SELOC manual I bought for the engine says .045. What should I gap these at?

Why I ask: Last year I was out on a small lake and could not get the boat to refire at all and had to be towed back. When I took it to the local mechanic they told me that the spark plugs were gapped wrong (so I double checked the book because I had a a hard time believing this). They regapped the plugs to whatver they thought they needed to be gapped at and the boat ran the rest of the summer without any issues.

Earlier this year I had the boat color restored by someone locally and they mentioned I should probably consider changing the distributor, wires and I went ahead and did the rotor and plugs as well. the boat fires fine gapped at .060 but am worried about not being able to get it started again this summer after what happened last summer and the conflict between the two manuals.

Appreciate any advise.
 
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What is the spark plug numbers,

.060" is typically for Platnium
.045" for standard type

So the part number is key from the manuals you are using.
 
The spark plugs I bought were MR43LTS which is what the Mercruiser book said to get for my engine with that gap (.060). THe SELOC manual specifies the exact same spark plug but with a .045 gap, thus my confusion
 
Your boat is carbed (TKS) and NOT EFI
Then .045" is the correct gap for that spark plug
 
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