Sierra
OMC GM Small Block V8 (1979-89) Sterndrive/Cobra Exhaust Manifold Exploded View
OMC Sterndrive/Cobra Exhaust Manifold Exploded View Diagram and Parts
Fits GM Small Block V8 305-350 cu. In.
1979-1989
Figure #DescriptionO.E.M. #Sierra #
1MANIFOLD (STARBOARD)912441 18-1902
2MANIFOLD (PORT)912442 18-1903
3ELBOW GASKET (Included in 18-8534 mounting kit. )909786 18-0943
4MANIFOLD ELBOW909863 18-1921
5MOUNTING BOLT (Included in 18-8534 mounting kit. )N/ANSS
6MANIFOLD GASKET (18-1903. Included in 18-8502 )96306 18-2949
7MOUNTING STUD (Included in 18-8502 mounting kit. )N/ANSS
8MOUNTING KIT (Includes 18-2949 manifold gasket. )N/A 18-8502 or 18-8550
9MOUNTING KIT (Includes 18-0943 elbow gasket. )N/A 18-8534
10HARDWARE KIT (Hardware only for Elbow 18-1921. )N/A 18-8553
11MANIFOLD ELBOWN/A 18-1909
12MOUNTING KITN/A 18-8507
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Manifold Perfect
by Richard from West Chester, Pennsylvania on August 01, 2017
Both exhaust manifolds were exact in every detail. Very nicely done in terms of price, shipping etc. Thank You.
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Q:
Is this for both sides?
A:
This is only one gasket to mount so there is only one side.


Q:
Will this fit my 1989 chevy 5 litter port side?
A:
This fits most GM V-8 small blocks with end riser. So it will depend on your engine type. If you have model number we should be able to cross reference if you need more assistance.


Q:
I have a 5.7GSPLKD the riser gaskets are bad and I would like to replace them. I would also like to replace the exhaust flapper and bushings. Volvo no longer sells them- Obsolete. Would also like 2 fuel and 2 water seperator filters.?
A:
For the gasket you need 18-4431-9 or OEM number 3863191. As for the flapper we do not offer it, OEM number is 3855517. As for the fuel/water separator filters, you need either part number 18-7989 or OEM number 3862228.


Q:
Do you have a Exhaust-Manifold-Elbow for a Volvo penta 7.5 GL??
A:
Unfortunately we will need to know the full model number to your engine to match up elbow. We do not list a 7.5GL, but we have different 7.4GL models. Please confirm.


Q:
Can I purchase the long?
A:
We will need to know engine application to see if we can match up manifold gasket.


Q:
The Volvo OEM part?
A:
Replaces Volvo OEM #'s: 835966 & 856034.


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Price: $18.43
Save: $8.56
(31% Off $26.99)
Part # 18-8507
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
Hurry! Only 1 left in stock
No Reviews
Replaces OEM part #
  • OMC 3856444
For:
  • OMC/Volvo GM Small Block V8 305-350 cu.in.

Used With:
  • Riser: 18-1909
Price: $10.81
Save: $5.17
(32% Off $15.98)
Part # 18-0943-1-9
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
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Pkg. of 2
Used with: 18-1909

Replaces OEM part #
  • OMC 909786
  • OMC 3850496
Price: $21.87
Save: $6.11
(21% Off $27.98)
Part # 18-2949-9
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
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Pkg of 2
Replaces OEM part #
  • CRUSADER 96306
  • BARR CHV-47-000
  • VOLVO 835966-3
  • VOLVO 856034-4
  • MERCURY MARINE 27-33395
  • MERCURY MARINE 27-33395B

Use with:
  • 18-1931-1: Manifold
  • 18-1986-1: Manifold
  • 18-1997-1: Manifold
  • 18-1902: Manifold
  • 18-1903: Manifold
  • 18-1904: Manifold
  • 18-1914: Manifold
  • 18-1925: Manifold
  • 18-1926: Manifold
  • 18-1950-1: Manifold
  • 18-1951-1: Manifold
  • 18-1953-2: Manifold
For:
  • AQ200, 225, 260, 271, 290, 311, V-8

Price: $209.94
Save: $60.05
(22% Off $269.99)
Part # 18-1909-1
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
Hurry! Only 1 left in stock
No Reviews
OMC Riser, 4" outlet 7 degrees. Fits many GM & Ford center rise manifolds
Use with:
  • Manifold: 18-1986
  • Riser Gasket: 18-0943
  • Mounting Kit: 18-8507


Replaces OEM part #
  • OMC 913784
  • OMC 3857944
  • OMC 3855270
  • OMC 3850456
  • VOLVO 3857944-7
  • VOLVO 3855270-9
  • VOLVO 3850456
Price: $196.49
Save: $91.50
(31% Off $287.99)
Part # 18-1902
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
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V-8 Starboard Side
Fits most GM V-8 small blocks with end riser
Use with: Mounting Kit 18-8502

Replaces OEM part #
  • OMC 912441
Price: $39.31
Save: $18.18
(31% Off $57.49)
Part # 18-8502
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
No Reviews
Fits:
  • OMC Gm Small Block V8 305-350 cu. in.
    ( 1979-89 ) OMC/Volvo GM Small Block 305-350 cu. in.

  • Use with: Manifolds 18-1931-1, 18-1902 & 18-1903, 18-1986. Includes mounting studs and hardware

Price: $156.19
Save: $63.80
(29% Off $219.99)
Part # 18-1921
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
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Fits most GM V-8 small blocks
Use with:
Manifold: 18-1902, 18-1903
Elbow Gasket: 18-0943
Mounting Kit: 18-8534

Replaces OEM part #
  • OMC 909863
Price: $196.49
Save: $91.50
(31% Off $287.99)
Part # 18-1903
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
Replaces OEM part #
  • OMC 912442 V-8 Port side
    Fist most GM V-8 small blocks with end riser
    Use with: mounting Kit: 18-8502
Price: $15.85
Save: $0.64
(3% Off $16.49)
Part # 18-8553
2nd Day Air for $2.99 More Eligible
No Reviews
Used with: Exhaust Elbow 18-1921
Price: $10.48
Save: $4.51
(30% Off $14.99)
Part # 18-8534
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
No Reviews
OMC GM Small Block V8 305-350 cu. in.
( 1979-1989 ) and multiple application
Ford and GM Risers
Used with: Riser 18-1921
Price: $192.99
Save: $56.89
(22% Off $249.88)
Part # 9-40911
2nd Day Air for $2.99 More Eligible
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
No Reviews
Riser
4" Exhaust outlet 7° down angle
Use 9-40672 mounting kit
OEM 913784, 3855270, 3850456, 3855270-9
Price: $201.99
Save: $68.01
(25% Off $270.00)
Part # 9-40601
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
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Manifold, Port
Fits 305 - 350 CID V-8
Includes hose and clamp
Use 9-40671 mounting kit
OEM 910144, 909279, 912442
Price: $201.99
Save: $73.69
(26% Off $275.68)
Part # 9-40602
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
No Reviews
Manifold, Starboard
Fits 305 - 350 CID V-8
Includes hose and clamp
Use 9-40671 mounting kit
OEM 909280, 912441
Price: $134.46
Save: $135.54
(50% Off $270.00)
Part # T-20903
SHIPS TODAY!* if ordered in 11 hrs 29 mins.
No Reviews

OMC Manifold, port


Replaces OEM #:

  • OMC 909312
  • OMC 908488

Engine Type:
GM Small Block V8 305-350 cu.in.


Engine Model Years:
1979 to 1989

Price: $212.87
(Out of stock)
Save: $146.13
(40% Off $359.00)
Part # T-20905
No Reviews

Mercruiser Elbow/Reservoir


Replaces OEM #:

  • Mercruiser 90880
Cap included.

Fits Mercruiser cast iron manifold #99908. Fitting not included.


Engine Type:
Mercruiser 3.7L engines


Engine Model:
165, 170, 180, 190, 470 and 3.7L

(Out Of Stock)