Name: Recmar MerCruiser 4.3 5.0 5.7L Lower Thermostat Housing 87290A4
Brand: RECAMBIOS
SKU: REC87290A4
Price: 343.14 GBP
Availability: InStock

Recmar MerCruiser 4.3 5.0 5.7L Lower Thermostat Housing 87290A4

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Our stock levels are dynamic and can change frequently. If a product appears to be in stock, it may have already sold out. Please contact us if you have any questions about availability. Thank you for your understanding.

£343.14

Tax included.

Recmar MerCruiser Lower Thermostat Housing

4.3L / 5.0L / 5.7L Center-Riser | 87290A4

Lower thermostat housing for selected MerCruiser GM 4.3L V6 and 5.0/5.7L small-block V8 engines with center-riser exhaust and the two-hose-bib upper-cover arrangement.

FITMENT CHECK: Match the lower-body casting, center-riser hose routing, upper cover and tee-ball port. Similar engines with flat-cap, dry-joint or closed-cooling housings use different parts.

Key Features

Lower thermostat housing body
For selected 4.3L, 5.0L and 5.7L GM engines
Center-riser / two-bib cover arrangement
Aftermarket Recmar; not genuine Mercury
Housing and fitted components supplied as pictured

Technical Specs

Part type	Lower thermostat housing
Engine family	GM V6 / small-block V8
Typical era	1983 and later where specified
Upper cover style	Two hose bibs / 47441A1 family
4Boats SKU	REC87290A4

Compatibility / Fitment Guide

Engine / system	Application	Required check
MerCruiser 4.3L V6	Selected center-riser engines	Parts diagram must list 87290A4/861006A1
MerCruiser 5.0L / 305 V8	Selected center-riser standard-cooling engines	Confirm tee-ball and upper-cover layout
MerCruiser 5.7L / 350 V8	Selected center-riser standard-cooling engines	Match casting, ports and serial diagram
Housing service	Systems using 47441A1 upper cover and tee-ball valve	Use 18-1989K-type service components where applicable

Not for flat-cap 17494A1, dry-joint exhaust or closed-cooling housing 55131A5. This is not the full 87290A23 conversion kit unless all conversion components are shown.

Part Number Cross Reference

Mercury / MerCruiser	87290A4; 861006A1; 8M0061381
Sierra	18-1989
Service kit reference	18-1989K
Barr Marine	MC-29-87290
GLM	13230
Recmar / 4Boats SKU	REC87290A4

Cross-reference numbers identify the housing design; verify the complete cooling-system diagram before ordering.

Frequently Asked Questions

Will it fit every 5.7L?
No. The engine must use the center-riser, two-bib/tee-ball housing design.

Is this the complete conversion kit?
No. See 87290A23 for the multi-piece conversion application.

Does it include the upper cover?
Only if shown; the lower housing is the specified part.

Will it fit closed cooling?
Not unless the exact parts diagram calls for this housing; 55131A5 is a common closed-cooling design.

Before ordering: match the lower casting, center-riser configuration and 87290A4/861006A1 reference.

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

Free delivery for most items over £150.

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Recmar MerCruiser 4.3 5.0 5.7L Lower Thermostat Housing 87290A4