Name: Recmar MerCruiser GM 305 350 V8 Lower Thermostat Housing 78984A08
Brand: RECAMBIOS
SKU: REC78984A08
Price: 325.61 GBP
Availability: OutOfStock

Recmar MerCruiser GM 305 350 V8 Lower Thermostat Housing 78984A08

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£325.61

Tax included.

MerCruiser GM V8 Lower Thermostat Housing

305 / 350 Small-Block | Type 1 Housing

Aftermarket lower thermostat housing for legacy MerCruiser GM 305 and 350 small-block V8 cooling systems using the 78984A08 / 861493 family.

FITMENT CHECK: The previous description incorrectly called this a Bombardier part. Fitment is MerCruiser; confirm Type 1/legacy log-style cooling layout and engine serial range.

Key Features

Lower thermostat housing
For GM 305 / 350 small-block V8
Legacy MerCruiser Type 1/log-style cooling system
Replaces 78984A08 and 861493 supersessions
Recmar aftermarket replacement

Technical Specs

Part type	Lower thermostat housing
Engine	GM small-block V8
Displacement	5.0L / 5.7L (305 / 350 cu in)
Cooling layout	Legacy Type 1 / log-style
SKU	REC78984A08

Compatibility / Fitment Guide

Engine / model	Verified application	Fitment checks
250 2-barrel / GM 350	Selected legacy 350 V8 models using 78984A08	Confirm serial-number parts diagram.
280 TRS GM 350	1975–1976 family, including serial range 4176250–4770199 where catalogued	Verify exact engine designation.
Other GM 305/350	Only installations using 78984A08 / 861493A3/A07	Later centre-riser housings differ.
Exclusion	OMC/Bombardier outboards; Ford V8; MerCruiser big-block	Incorrect brand/architecture.

Compare casting, hose-port arrangement, upper/lower interface and engine serial-number parts diagram.

Part Number Cross Reference

MerCruiser	78984A08; 78984A1; 78967; 78459A1
MerCruiser supersession	861493A3; 861493A07
Sierra	18-1993; 18-1910
GLM	13530
4Boats SKU	REC78984A08

Aftermarket replacement; manufacturer references are used for identification only.

Frequently Asked Questions

Is this an OMC/Bombardier part?
No. The verified application is MerCruiser GM V8.

Does it fit every 5.7L?
No. It is for the legacy housing system using 78984A08.

Is the upper cover included?
No; this listing is for the lower housing shown.

Installation note: Clean mating faces, replace gaskets/O-rings and confirm unobstructed coolant flow before running the engine.

For the products under £150 the shipping is £6.99.

Free delivery for most items over £150.

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Recmar MerCruiser GM 305 350 V8 Lower Thermostat Housing 78984A08