Are you tired of a dead turn of the key when you are ready to hit the water? I compared these two ignition replacements using buyer feedback to see which one actually delivers. In my view, matching your exact factory specifications matters more than saving a few dollars. Let us look at how they rank before you buy.
| Best For | Product | Name | Score | |
|---|---|---|---|---|
| Exact Mercury Replacements |  |
87-88107A5 Boat Ignition Switch with 2 Keys 6 Wire Connectors Compatible with Mercury Outboard Motor Key Push Choke Ignition Replace# 87-88107, 87-88107A5, 7-1155 | 9.8/10 | View on Amazon |
| General Sierra Compatibility |  |
MP41000 Marine Ignition Switch Fit for Most Mercucy Sierra Models | 8.2/10 | View on Amazon |
1. 87-88107A5 Boat Ignition Switch with 2 Keys 6 Wire Connectors Compatible with Mercury Outboard Motor Key Push Choke Ignition Replace# 87-88107, 87-88107A5, 7-1155
This unit earned the top spot in my ranking because of its direct six-wire configuration. It replaces factory parts without forcing you to cut or splice your existing wiring.
I would point most boat owners straight to this option for its push-choke functionality. The construction feels solid enough to resist the usual marine corrosion.
You might occasionally find the mounting bezel a bit tight during initial installation. Still, I think the factory-matched fit justifies minor installation patience.
Buyers frequently mention that the wire colors match the original harness perfectly.
Several users note that the push-choke mechanism operates smoothly right out of the box.
Reviewers appreciate the inclusion of two fresh keys with the assembly.
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2. MP41000 Marine Ignition Switch Fit for Most Mercucy Sierra Models
This switch is best for boaters who need a dependable spare for Sierra-compatible setups. It targets users looking for a budget-friendly alternative to branded OEM parts.
I consider this a decent backup plan for general marine repairs. The universal design fits a broad range of older dashes.
The main drawback is that you may need to verify terminal positions before final wiring. I would double-check your specific console layout to avoid any wiring confusion.
Users report that it fits standard dashboard cutouts without major modifications.
Some buyers point out that terminal markings require careful reading during setup.
Reviewers note it functions reliably as an emergency replacement part.
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Choosing Between Them
I recommend the 87-88107A5 ignition switch for your primary setup because its exact factory compatibility saves you from wiring headaches. If you just need a general backup for Sierra models, the MP41000 serves that purpose adequately.
Always verify your outboard wiring harness before turning the key for the first time. Electrical quirks on older boats can quickly ruin a weekend on the water.
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