# 21663837 Shim | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta D6 and D7 Cylinder-Liner Spacer-Ring Shim, selective intermediate thickness - Part Number: 21663837 A selective spacer-ring shim used during D6 and D7 cylinder-liner service to establish the specified liner protrusion above the cylinder-block deck.

## ⚙️ Key Features

-   Nominal selection: selective intermediate thickness
-   Cylinder-liner protrusion adjustment
-   Precision-ground hardened steel
-   Selected only after liner-height measurement
-   Used during cylinder-block and liner repair

## 🔌 Function

The shim raises the cylinder liner by a controlled amount so the head gasket is clamped correctly and combustion pressure remains sealed.

## ⚠️ Common Signs of Failure

-   Incorrect liner protrusion
-   Repeated cylinder-head gasket failure
-   Coolant pressurisation
-   Shim compressed, corroded or damaged during removal

## 🛠️ Service Notes

-   Shims are supplied in graded thicknesses and exist to bring a setting into specification, so measure with a micrometer and select the thickness the setting procedure for your engine calls for rather than matching one by eye
-   Note which shim came from which position on removal and keep them identified — once an assembly has bedded in, shims are not interchangeable between positions
-   Check both faces are clean, flat and free of burrs, corrosion and old sealant before fitting; dirt trapped under a shim shifts the setting as surely as the wrong thickness does
-   Discard any shim that is dished, cracked, pitted or fretted rather than reusing it, and make sure no old shim has been left behind in the recess
-   Recheck the clearance or setting after the assembly is tightened down, because clamping load can change the measurement you took loose

## 🔄 Supersession & Cross Reference

### OEM / Related Numbers

-   21663836-21663840 - Selective spacer-ring shim family

## 📦 Condition

-   Genuine Volvo Penta part
-   Brand new
-   Supplied in original or equivalent packaging

## Details

- **Price:** 88.02 AUD
- **Vendor:** Volvo Penta
- **Type:** Fasteners & Fixings
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 88.02 AUD | In stock |

## Images

- 21663837 Shim | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/21663837-shim-genuine-volvo-penta)
> Updated: 2026-10-10