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Mercury MerCruiser Quicksilver TKS Carburetor Idle Mixture Adjusting Tool 866201

Original price $12.74 - Original price $12.74
Original price $12.74
$12.74
$12.74 - $12.74
Current price $12.74
Availability:
Only 2 left!
In stock items ship same or next day.

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Mercury / MerCruiser TKS Carburetor Idle Mixture Adjusting Tool

Part Number: 866201 | Specialty Tool Reference: 91-866201
Brand: Mercury Marine | GTIN: 745061662438

Genuine Mercury OEM specialty service tool for adjusting the idle mixture screw on TKS MerCarb carburetors. The TKS MerCarb uses a capped idle-mixture screw that requires this dedicated tool — a conventional screwdriver or socket will not work.

What This Tool Does

Use this tool to perform approved idle-mixture adjustments on TKS MerCarb carburetors. Mercury service procedure specifies that idle-mixture adjustment must be performed only after the engine is fully warmed up and the TKS enrichment circuit has shut off. Always follow the applicable Mercury MerCruiser service manual.

Compatible Applications

  • MerCruiser 3.0L engines equipped with TKS MerCarb carburetor
  • MerCruiser V6 engines equipped with TKS MerCarb carburetor
  • MerCruiser V8 engines equipped with TKS MerCarb carburetor

Confirm your engine uses a TKS MerCarb and that Mercury service information specifies tool 91-866201 for the adjustment procedure before ordering.

Important Fitment Notice

This is a specialty service tool — not a replacement carburetor component. It is designed exclusively for TKS MerCarb carburetors. Do not confuse with Mercury 86197, which is the idle-mixture socket used on Rochester 4-barrel carburetors. These are two different tools for two different carburetor families.

Kit Contents

  • 1 × Mercury 866201 TKS idle mixture adjusting tool

Alternate Part Numbers

  • Mercury OEM: 866201
  • Specialty Tool Reference: 91-866201
  • GTIN: 745061662438

Parts Desk Insights

The key identifier when selecting this tool is TKS MerCarb. Customers servicing Rochester 4-barrel carburetors need a different tool entirely. If a customer is unsure which carburetor system their engine uses, have them check the carburetor casting or cross-reference the engine serial number with the Mercury parts catalog before ordering.

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 1-3 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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