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Add-On Steering Systems

Sterndrive Hydraulic Cylinders

HYDRAULIC CYLINDERS or sometimes called rams are the primary consideration in hydraulic steering systems as they are where the action is! All the hydraulic force of the system is converted to linear motion as the cylinder extends and retracts, moving the sterndrive or outboard. At Latham Marine, we produce high quality, rugged stainless steel thick wall cylinders with incredibly smooth bores using computer controlled precision manufacturing techniques, proven by years of offshore victories and trouble free operation. All cylinders are pressure tested before shipping, to assure you of dependable, trouble free operation.

The Sterndrive Cylinder

THE STERNDRIVE CYLINDER is equipped with a stainless steel transom mount and integral clevis joint which allows pivoting action in two planes. Fluid ports are 1/4″ NPT and four standard stroke lengths are available, with a choice of polished or white powder coat transom mounts. All part numbers are for one cylinder and mount assembly. Some applications require multiple cylinders – consult your sales specialist.

STERNDRIVE CYLINDER PART NUMBERS

Stroke Standard Clevis Joint / Polished Mount Medium Clevis Joint / Polished Mount
7"
KRSD-9384
KRSD-9388
8"
KRSD-9385
RSD-9389
9"
KRSD-9386
KRSD-9390
10"
KRSD-9387
KRSD-9391
Stroke Standard Clevis Joint / White Mount Medium Clevis Joint / White Mount
7"
KRSD-9508
KRSD-9512
8"
KRSD-9509
KRSD-9513
9"
KRSD-9510
KRSD-9514
10"
KRSD-9511
KRSD-9515

Sterndrive Mounting Plates

MANY PERFORMANCE STERNDRIVE INSTALLATIONS require special mounting plates and brackets to connect external steering and tie bars. All LATHAM sterndrive plates are made from 316 stainless, computer machined for accurate fit, and polished for long lasting beauty. Attaching hardware is included unless otherwise noted.

ALPHA® MOUNT

The original MCM I drive has been revised several times; first as the Alpha Drive and now the Generation II. All kits include mounting bolts and spacers.

PLSD-2773
ALPHA, STEERING/TIE BAR PLATE
PLSD-8517
GENERATION II TIE BAR PLATE
PLSD-8518
GENERATION II STEERING AND TIE BAR PLATE

BRAVO® MOUNT

MerCruiser’s Bravo drive has been the standard on virtually every brand of performance boat for almost two decades. The Bravo drive is also available in the Bravo One X® and XR® models for higher power applications and requires a different steering mount. The LATHAM BRAVO BOLT-ON STEERING MOUNTS are bolted directed onto the stock drive requiring no removal of the stock rear cover or drainage of the drive oil. Mounting studs and lock nuts are included for increased strength.

KPLT-7905

MCM BRAVO BOLT-ON MOUNT - 2005+

KPLT-7914

MCM BRAVO X/XR BOLT-ON MOUNT- 2005+

KPLT-7627

MCM BRAVO BOLT-ON MOUNT - PRE 2005

KPLT-7069

MCM BRAVO CENTER TOP PLATE

KPLT-7070

MCM BRAVO CENTER TOP PLATE - REV. ANGLE BRKT.

KPLT-7071

MCM BRAVO X/XR CEN. PLATE - REV. ANGLE BRKT.

KPLT-7409

MCM BRAVO / STELLINGS PLATE - 8" RH

KPLT-7410

MCM BRAVO / STELLINGS PLATE - 9" RH

KPLT-7418

MCM BRAVO / STELLINGS PLATE - 8" LH

KPLT-7419

MCM BRAVO / STELLINGS PLATE - 9" LH

TRS® REAR MOUNT

The TRS drive brought offshore powerboating to the masses in the 1970’s. This tough sterndrive is still on a lot of transoms, and still going fast! LATHAM’S TRS REAR MOUNT attaches over the stock rear cover on studs (studs and lock nuts are included). Fits stock TRS, TR2, and TRS Speedmaster and allows attachment of rams and/or clevis tie bars.

PLSD-2150
MCM TRS REAR MOUNT

MCM III®, IV® and V® WING AND WRAP PLATES

These drives have been used successfully in offshore racing since the ’60’s. Speedmaster became a familiar term if you wanted to stay competitive. All these drive variations share the same bolt pattern for attaching plates to the Merc rear steering cover. The correct combination of plates is primarily determined by application; i.e. hull type, racing or pleasure, etc. Special wing plates are required for drives on extension boxes, and the cylinders must have medium clevis joints. Call your sales consultant for details.

PLSD-2190
WRAP-AROUND PLATE, CENTER
PLSD-2200
WRAP-AROUND PLATE, OUTSIDE
PLSD-2210
ONE WING WRAP-AROUND PLATE

TIE BAR PLATES

TIE BAR PLATES for IV and V drives bolt to back of driveshaft housing above rear anchor pin. Mounting studs and lock nuts are included (machining of housing is required).

PLSD-2240
MCM V TIE BAR PLATE FOR LRG. CLEVIS

MERCRUISER VI® & 6A® TIE BAR MOUNTS

MERCRUISER VI® & 6A® TIE BAR MOUNTS provide solid mounting points for a clevis tie bar. Built of 316 stainless steel, they attach to the four studs built into the VI drive, or to the top of the 6A drive. Bolt kits to attach tie bar clevis joints to mounts are included.

KPLT-7139

MCM 6A MOUNT, LRG. CLVS, EAR BELOW

KPLT-7661

MCM 6A MOUNT, LRG. CLVS, EAR ABOVE

KPLT-8575

MCM 6A MOUNT, XLG. CLVS, EAR ABOVE

PLSD-9100

MCM VI MOUNT FOR VEE HULLS

PLSD-8507

MCM VI MOUNT FOR CATAMARANS

KONRAD 540 HP STERNDRIVE® STEERING / TIE BAR PLATE

KONRAD 540 HP STERNDRIVE® STEERING / TIE BAR PLATE is designed to bolt directly to the 4 bolt holes on the rear cover without any modification to the drive. It is a universal design allowing attachment of either single or dual rams and a tie bar attaching hole on the drive center allowing smooth synchronization of multiple drives.

KPLT-7974
KONRAD DRIVE STEERING MOUNT KIT

Mercruiser Alpha, Bravo One, Bravo One XR, Bravo One XZ,TRS, III, IV, V, VI & 6A are all registered trademarks of the Brunswick Corporation. Konrad 540 HP Sterndrive is a registered trademark of Konrad Marine.

Sterndrive Tie Bars Assemblies

ALL MULTIPLE DRIVE INSTALLATIONS require one or more tie bars to keep the drives parallel and equalize loading. Boats running 65 mph or more with multiple sterndrives should use an external tie bar assembly; either in addition to an internal tie bar or by itself, if used in conjunction with Latham external steering. Using only an external clevis bar will allow the driver greater latitude for independent trimming and tilting without damage to tie bar or drive components. The same principles apply to outboards with front and rear tie bars.

LATHAM MARINE INC. TIE BARS are constructed from 316 stainless steel and satin finished for maximum corrosion resistance. Solid bars are used up to 36″ long. And tubular construction is utilized for longer bars.

CLEVIS JOINT BARS

CLEVIS JOINT BARS are available with four sizes of clevis joints in solid or tubular bars. Special bolt kits MUST be used with clevis joints.

CLEVIS JOINT BARS

TBAR-4560

1-1/8" BAR WITH STANDARD CLEVIS

TBAR-4570

1-1/4" BAR WITH LARGE CLEVIS JOINTS

TBAR-4490

1-1/4" BAR WITH LARGE CLEVIS JOINTS

TBAR-8508

1-1/4" BAR WITH LARGE SCISSORS CLEVIS

TUBULAR BARS

TBAR-4730

1-3/8" BAR WITH MEDIUM CLEVIS JOINTS

TBAR-4770

1-5/8" BAR WITH MEDIUM CLEVIS JOINTS

TBAR-4780

1-5/8" BAR WITH LARGE CLEVIS JOINTS

TBAR-4280

2" SUPER BAR WITH X-LARGE CLEVIS JOINTS

CLEVIS JOINT TIE BAR ASSEMBLIES

KTBR-8485

MCM I®/ ALPHA® ASSEMBLY W/STANDARD CLEVIS

KTBR-8581

ALPHA GENERATION II® ASSEMBLY W/STD. CLEVIS

KTBR-4702

BRAVO® ASSEMBLY With Standard Clevis

KTBR-1585

TRS® ASSEMBLY WITH STANDARD CLEVIS

KTBR-4662

TRS HD® ASSEMBLY WITH STANDARD CLEVIS

KTBR-8453

MCM III® ASSEMBLY WITH LARGE CLEVIS *

KTBR-8454

MCM IIIA® ASSEMBLY WITH LARGE CLEVIS *

KTBR-4870

MCM VI® TIE BAR KIT FOR VEE HULLS - LARGE CLEVIS

KTBR-4880

MCM VI® TIE BAR KIT FOR CATS - X-LARGE CLEVIS

KTBR-4970

MCM 6A® TIE BAR KIT - VEE - EAR ABOVE - LRG CLEVIS

KTBR-4975

MCM 6A® TIE BAR KIT - VEE - EAR BELOW - LRG CLEVIS

KTBR-4980

MCM 6A® TIE BAR KIT - CAT - X-LARGE CLEVIS

KTBR-7415

VOLVO SX®/DPS® ASSEMBLY WITH STANDARD CLEVIS

KTBR-7438

VOLVO DPX® ASSEMBLY WITH STANDARD CLEVIS

* Long Anchor Pins Required

ROD END TIE BAR ASSEMBLIES

KTBR-4601

MCM I® ASSEMBLY WITH 1/2" AHT ROD ENDS

KTBR-4610

MCM I® ASSEMBLY WITH 5/8" AHT ROD ENDS

KTBR-4702

BRAVO® ASSEMBLY With Standard Clevis

BRAVO® MOUNT

TIE BAR SADDLES can be purchased separately as replacement items. All tie bar saddles are made from 316 stainless and mirror polished, and can be ordered for rod ends or clevis joints. Heavy duty saddles for MCM TRS, III, IV and V drives require long anchor pins (sold separately). IV & V drives cannot use saddles with 1″ drive spacers.

SADL-4800

MCM I SADDLE FOR 1/2" ROD END

SADL-4820

MCM I SADDLE FOR 5/8" ROD END

SADL-8353

MCM I SADDLE FOR STANDARD CLEVIS

SADL-4860

BRAVO SADDLE FOR 3/4" ROD END

SADL-1540

BRAVO SADDLE FOR STANDARD CLEVIS

SADL-1543

BRAVO SADDLE FOR STD. CLEVIS W /SPACER - '05+

SADL-4810

TRS SADDLE FOR 3/4" ROD END

SADL-4282

TRS HD SADDLE FOR 3/4" ROD END*

SADL-1550

TRS SADDLE FOR STANDARD CLEVIS

SADL-4283

MCM III SADDLE FOR 3/4" ROD END*

SADL-4286

MCM III SADDLE FOR LARGE CLEVIS*

SADL-4290

MCM IIIA SADDLE FOR LARGE CLEVIS*

SADL-2260

MCM IV SADDLE FOR LARGE CLEVIS*

SADL-7415

VOLVO SX/DPS SADDLE FOR STANDARD CLEVIS

PINS-3318

TRS LONG ANCHOR PIN

PINS-3320

MCM III LONG ANCHOR PIN

PINS-3321

MCM IIIA LONG ANCHOR PIN

WARNING: WHEN USING TIE BARS, DRIVES MUST BE TRIMMED AND TILTED TOGETHER TO AVOID DAMAGE TO TIE BARS OR DRIVES

LATHAM MARINE CLEVIS JOINTS

LATHAM MARINE CLEVIS JOINTS allow sterndrives or outboards to be trimmed and tilted independently to a much greater extent than typical spherical rod ends. Constructed of stainless steel to exacting tolerances, clevis joints must be used with special bolt kits to provide the proper fit on the clevis poly bushings. Four sizes of male clevis joints are available depending on duty level, and clevis joints are supplied as an integral part of the steering cylinders. Scissors clevis joints are used on triple applications where two tie bars meet at a center point, and allow both bars to attach right on the drive’s centerline.

CLVS-1075

STANDARD, MALE 3/4-16 THREADS

CLVS-1076

STANDARD, FEMALE 5/8-18 THREADS

CLVS-1077

MEDIUM, MALE 3/4-16 THREADS

CLVS-1078

MEDIUM, FEMALE 5/8-18 THREADS

CLVS-1079

LARGE, MALE 7/8-14 THREADS

CLVS-1080

X-LARGE, MALE 1-1/4-12 THREADS

CLVS-4999

MEDIUM SCISSORS CLEVIS

CLVS-5000

LARGE SCISSORS CLEVIS

WARNING: WHEN USING TIE BARS, DRIVES MUST BE TRIMMED AND TILTED TOGETHER TO AVOID DAMAGE TO TIE BARS OR DRIVES

LATHAM MARINE ROD ENDS

LATHAM MARINE stocks a large supply of stainless steel, Teflon lined spherical rod ends. These are available in standard AHT SERIES or heavy duty ART SERIES, and are made from several different grades of stainless. Thread size and hole size are the same, and all threads are National Fine Thread.

STANDARD SERIES

RDEN-6010

AHFT3 10-32 FEMALE RH 303

RDEN-6011

AHMT6 3/8-24 MALE RH 303

RDEN-6021

AHMT8 1/2-20 MALE RH 316

RDEN-6022

AHMTL8 1/2-20 MALE LH 316

RDEN-6015

AHMT10 5/8-18 MALE RH 303

RDEN-6016

AHMTL10 5 / 8-18 MALE LH 303

RDEN-6026

AHFT10 5/8-18 FEMALE RH 316

RDEN-6018

AHMT12 3/4-16 MALE RH 303

RDEN-6019

AHMTL12 3/4-16 MALE LH 303

RDEN-6020

AHFT12 3/4-16 FEMALE RH 303

ART SERIES - HEAVY DUTY

RDEN-6030

ART6-ECR 3/8-24 MALE RH 17-4PH

RDEN-6008

ART8-ECR 1/2-20 MALE RH 316

RDEN-6033

ART10-ECR 5/8-18 MALE RH 17-4PH

RDEN-8416

ARTL10-ECR 5/8-18 MALE LH 17-4PH

RDEN-6032

ART10CR 5/8-18 FEMALE RH 17-4PH

RDEN-6034

ART12-ECR 3/4-16 MALE RH 17-4PH

RDEN-6037

ARTL12-ECR 3/4-16 MALE LH 17-4PH

* PLEASE NOTE: Jam nuts sold separately.
Mercruiser MCM I, Alpha, Alpha Generation II, Bravo One, Bravo One XR, Bravo One XZ,TRS, III, IV, V, VI & 6A are all registered trademarks of the Brunswick Corporation. Volvo SX, DPS and DPX are all registered trademark of Volvo Penta of the Americas, Inc.

Sterndrive Bolt Kits

ATTACHING HARDWARE

ATTACHING HARDWARE – Steering rams, mounting plates and tie bars require special bolts and spacers to attach them to plates or mounts. Clevis joints require stepped bolts with the exact length to allow proper operation and prevent damage to the clevis bushings.

KBLT-1035

BOLT KIT: 5/8" X 2-3/4" - LINK TO TRANSOM MOUNT

KBLT-1036

BOLT KIT: 5/8" X 3" - RAM TO LINK

KBLT-1523

BOLT KIT: 3/8" X 3-3/4" - Sterndrive Ram Mount Through Transom

KBLT-2750

BOLT KIT: STANDARD CLEVIS BETWEEN EARS

KBLT-2751

BOLT KIT: STANDARD CLEVIS ABOVE EAR, NO RAM

KBLT-2752

BOLT KIT: MEDIUM CLEVIS ABOVE EAR, NO RAM

KBLT-2757

BOLT KIT: STANDARD CLEVIS BELOW EAR, NO RAM

KBLT-2758

BOLT KIT: MED./LRG. CLEVIS BELOW EAR

KBLT-2760

BOLT KIT: Std. Clevis Below Ears And Rod End To Bravo / Trs Mount

KBLT-2763

BOLT KIT: STANDARD CLEVIS TO 3/8" PLATE

KBLT-2767

Bolt Kit: Standard Clevis Below And Between Ears On Bravo/Trs Mount.

KBLT-2768

BOLT KIT: MED./LRG. CLEVIS ABOVE EARS, STANDARD CLEVIS BETWEEN EARS.

KBLT-2770

BOLT KIT: MED./LRG. CLEVIS BELOW, STD.CLEVIS BETWEEN EARS.

KBLT-2893

BOLT KIT: LARGE CLEVIS TO MERC #6 MOUNT

KBLT-1456

BOLT KIT: X-LARGE CLEVIS TO 6-A TOP MOUNT PLT.

KBLT-6030

BOLT KIT: 1/2" X 4" - RAM TO MCM III,IV & V DRIVE

KBLT-6310

BOLT KIT: 1/2" X 4" - WRAP PLATE TO MCM III,IV & V

KBLT-7689

BOLT KIT: MED./LRG. CLEVIS BRAVO XR, BET. EARS

KBLT-7776

BOLT KIT: STANDARD CLEVIS BETWEEN AND BELOW EAR ON B-MAX MOUNT.

KBLT-7438

BOLT KIT: STD. CLEVIS TO VOLVO DPX - TIE BAR

KBLT-7866

BOLT KIT: LINK TO TRANSOM MOUNT

KBLT-7867

BOLT KIT: RAM TO LINK

KBLT-8502

BOLT KIT: MEDIUM CLEVIS TO WING PLATE

KBLT-8700

Bolt Kit: Medium Clevis To Bravo /Stellings Top Plate W/Ear.

Mercury Controller Valve

LATHAM ADD-ON STEERING SYSTEMS

LATHAM ADD-ON STEERING SYSTEMS are a good compromise between and an economical steering system for boats with Mercruiser® sterndrives with factory power steering and the high quality and durability associated with the Latham Full Power Systems. The stock steering cable and helm diverts the hydraulic flow through the Mercury® controller valve on the inner transom plate to the Latham external hydraulic cylinders. These systems include the same steering cylinders, mounting brackets, tie bars and attaching hardware as in the full power systems. Steering effort is low, but there is no valve to lock out propeller torque and the system is not as responsive as the full power system. The stock Mercury® controller valve requires modification by Latham Marine to be used in the ADD-ON configuration.

LATHAM ADD-ON STEERING SYSTEMS

LABR-2000 MODIFICATION TO CONTROLLER VALVE

Mercruiser and Mercury are registered trademarks of the Brunswick Corporation.