Thermostat Housing Sleeve 23-806922 8M0214947 17495 805532 for MerCruiser Mercury V6 V8 4.3 5.0 5.7 7.4 8.2 L
Thermostat Housing Sleeve 23-806922 8M0214947 17495 805532 for MerCruiser Mercury V6 V8 4.3 5.0 5.7 7.4 8.2 L
Product Overview
Thermostat housing sleeve for MerCruiser V6 and V8 sterndrive engines, the stainless retainer that holds the thermostat in the housing on 3.7 L, 4.3 L, 5.0 L, 5.7 L, 7.4 L and 8.2 L GM blocks. It replaces 23-806922 and the later 8M0214947 number and crosses to 17495, 174951 and 805532. One sleeve is supplied.
This is not the thermostat and not the gasket. It is the thin stainless ring that sits between the thermostat flange and the housing bore, and it is the part that goes missing when a thermostat is changed on the dock and the old sleeve is left out.
Without it the thermostat cocks in the bore, the housing will not seal and the engine runs cold or leaks from the housing joint. The sleeve is only a few tenths of a millimetre thick, so check the housing bore for corrosion before fitting a new one.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Thermostat housing sleeve, retainer ring |
| Material | Stainless steel |
| Fits | MerCruiser 4-cylinder and V6 V8 GM based engines |
| Net Weight | 60 g including packaging |
| Pack Size | 15 x 18 x 1 cm |
| Quantity | 1 sleeve |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| MerCruiser / Quicksilver | 23-806922, 806922 |
| MerCruiser, later number | 23-8M0214947, 8M0214947 |
| Cross reference | 17495, 174951, 805532 |
Compatible Engines
| Engine Family | Displacement | Housing |
|---|---|---|
| 4-cylinder GM | 2.5 L, 3.0 L | Single thermostat housing, one sleeve |
| 4-cylinder GM 3.7 L | 224 cu in, 470 and 488 | Aluminium housing, check the bore |
| V6 GM | 4.3 L | Same sleeve as the V8 housing |
| V8 GM | 5.0 L, 5.7 L | Single thermostat, one sleeve |
| V8 GM big block | 7.4 L | Same sleeve, wider housing flange |
| V8 GM 502 | 8.2 L | Same sleeve, check the housing part number |
What's Included
| Component | Reference | Qty |
|---|---|---|
| Stainless thermostat housing sleeve | 23-806922 pattern | 1 |
| Thermostat | Not included, order separately | 0 |
| Housing gasket | Not included, order separately | 0 |
Symptoms of a Missing or Rusted Sleeve
| What You See | What It Means | What To Do |
|---|---|---|
| Coolant weeps at the housing joint | Thermostat not sitting square in the bore | Fit the sleeve, then a new gasket |
| Engine runs cold at cruise | Thermostat cocked open by the bore | Check the sleeve and the thermostat flange |
| Housing bolts will not pull down | Sleeve missing, thermostat standing proud | Fit the sleeve before torqueing |
| Rust ring on the old thermostat | Sleeve corroded away | Renew the sleeve with the thermostat |
| Overheat straight after a service | Sleeve fitted on the wrong side | Strip and refit with the ring under the flange |
| Fresh water cooled motor | Heat exchanger housing, same sleeve | Check the housing number first |
Thermostat Housing Sequence
| Position | Component | Note |
|---|---|---|
| 1 | Housing lower half | Clean the bore, no old gasket left behind |
| 2 | Thermostat, spring down | Jiggle pin at the top if the thermostat has one |
| 3 | Stainless sleeve | This part, sits over the thermostat flange |
| 4 | Housing gasket | Dry fit, no sealant on a rubber gasket |
| 5 | Housing cover | Torque evenly in a cross pattern |
| 6 | Coolant refill and bleed | Run to temperature and check for leaks |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the number on the old sleeve, 23-806922 and 8M0214947 are the same part |
| 2 | Drain the coolant below the housing before opening it |
| 3 | Clean the housing bore with a Scotch pad, corrosion pushes the sleeve off square |
| 4 | Check the thermostat flange for a rust ring, that is where the sleeve sat |
| 5 | Fit the sleeve over the thermostat flange, not under it |
| 6 | Fit a new gasket and torque the housing bolts evenly |
| 7 | Refill and bleed the cooling system before the engine is loaded |
| 8 | Run to temperature and check the housing joint for weeping |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Check the number on the old sleeve, 23-806922 and 8M0214947 interchange
- Fits MerCruiser 2.5 L, 3.0 L, 3.7 L, 4.3 L, 5.0 L, 5.7 L, 7.4 L and 8.2 L
- This is the stainless sleeve only, thermostat and gasket are not included
- Clean the housing bore before fitting, corrosion distorts the seal
- Fit the sleeve over the thermostat flange, not under it
- Refill and bleed the cooling system after the job
- 30-Day Easy Returns
- Ships from our warehouse with tracking
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Before You Buy
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