Alpha one lower unit gear ratio

Complete SEI sterndrives do not include the assembly or mounting hardware. Kits are available in our Ebay store. Kit part number K includes all assembly hardware, mounting hardware, O-rings and gaskets for mounting the drive, brass intermediate shift shaft and the guide tube for the water pump. Kit part number K includes all anodes for a Gen 1 drive. The unit is covered for three years for breakage and damage; including failures resulting from lack of oil, fishing line, impact and other abuse.

Please see the image below to verify the yoke length you need. The two styles are not interchangeable. Please see the images below and compare them to your existing sterndrive to determine that you are ordering the correct style replacement sterndrive. Your Mercruiser Sterndrive must have trim and tilt to be able to use our replacement drive.

Ships in two boxes. Please see related items below. To determine if you have a counter rotation unit on your twin engine boat it is easiest to look at the props. If the props are identical orientation, then they are both standards. If the prop blades are opposite, then the port should be a counter rotation. Please refer to the model chart below to find your proper gear ratio.

Rotation Upper All Lower Std. Lower C. See 1 and up 2,4,5,6 1. Inline 4 Cyl. V8 2 Barrel Carb. V8 7. You could substitute a 1.Complete water pump impeller repair kit. Includes Housing, liner, impeller, water tube, and all necessary gaskets, o-rings and seals.

Made in the USA. Complete with and all the necessary seals and o-rings, impeller and all new and improved wear plate with integrated rubber gasket. Water drain fitting for exhaust manifolds, water distribution housings, and drain fittings on Mercruiser engines.

Under the same ownership for over 60 years, we have continued to provide the finest products and service in the industry. Doug Russell Marine maintains one of the most extensive parts department in the world with more thanparts, and over 1, sterndrives and engines in stock!

Backed by these brand names and over 60 years experience, we continue to offer the best brands in the business. Over the years we have acquired the knowledge, experience and inventory second to none. Our profound buying power gives us the ability to offer the best prices in the industry. Nobody comes close. Our factory trained technicians and dedicated sales staff are passionate about their work. We pride ourselves in taking the time to work with each individual, to ensure you are properly matched within your budget and technical needs.

About Us Doug Russell Marine was founded in and is located west of Boston in Worcester, Massachusetts Under the same ownership for over 60 years, we have continued to provide the finest products and service in the industry. All rights reserved.These units are new, not remanufactured, which means it has no wear and tear yet. You may use the chart to determine your gear ratio. You can select the gear ratio from the drop down under 'available options' on this page. We can supply 1.

Replaces most Mercruiser Sterndrives from HP 2. Your Mercruiser Sterndrive must have trim and tilt to be able to use our replacement drive. If your Mercruiser Sterndrive is between you must verify that you have 13 splines on your upper driveshaft. Ships in two boxes. Please see related items below.

To determine if you have a counter rotation unit on your twin engine boat it is easiest to look at the props. If the props are identical orientation, then they are both standards. If the prop blades are opposite, then the port should be a counter rotation 7.

SEI Marine SE106 MerCruiser Alpha One Gen 1 Lower Unit (All Ratios)

Please refer to the model chart below to find your proper Mercruiser Sterndrive Replacement. These are typical applications, it is best to confirm your ratio by counting the teeth in the upper. Although great care was taken in the creation of this guide, SEI cannot guarantee its accuracy. Notes 1. Unit has an 8 spline driveshaft on the lower unit. If your unit is original, you need to purchase a complete. Unit has a short yoke on the upper driveshaft.

Unit must have trim and tilt for our Replacement to work. If it has two trim hoses going to each cylinder, it has trim and tilt. Unit has an eyelet on top cover. Replacement unit will not. Unit has a round cavitation plate on lower unit.

The replacement will not. Gear Ratio must be confirmed. Chart below is typical applications, however there is no guarantee it is correct. To be safe it is best to remove the top cover and count the teeth on the upper gears. SEI does not make this gear ratio. You could substitute a 1. Product Menu. It's a great replacement for the 6E Browse Products. Trolling Motors. Service Manuals.Mercruiser outdrives Alpha 1 lower unit gearcase housing assembly from SEI Marine aftermarket replaces the original Alpha 1 and Mercruiser lower gear housings.

alpha one lower unit gear ratio

For β€” models, serial numbers OD For and up models with metal water pump and impeller housing, serial numbers ODUp. For β€” models, serial numbers to For β€”models with horsepower inline six cylinders, 1. Compatible with,S,5. For β€” up models with four-cylinder motors, 1. For β€” up models with 4. A condition of qualification of these warranties is proof of purchase of the SEI product.

These warranties commence on the shipment date of products to the customer sold by TC Electronics to the purchaser. Your email address will not be published. This site uses Akismet to reduce spam.

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Mercruiser Gear Ratio Chart

I don't like walking on the beach, but I love playing the guitar and geeking out about music. I am also a movie maniac and 6 hours sleeper. Leave a Reply Cancel reply Your email address will not be published.Search the Web:. Posts: Status: First Lieutenant.

Is a Bravo Drive Better Than an Alpha Drive

Gallery Images: 0. Thanks: 0. Send Medic a Private Message. How do I find my gear ratio?? I have a 28' Z with a 7. I am going to bite the bullet and replace the lower unit due to corrosion. I am having trouble finding the gear ratio. There was a stamped serial number on the upper unit which has since fallen off.

Does anyone have a similar setup to advise me the proper gear ratio?

alpha one lower unit gear ratio

Thanks in advance. Posts: 2, My Year: Gallery Images: Thanks: 3. Send WetWilly: a Private Message. Re: How do I find my gear ratio?? Hi Medic, found this info and since you're taking off the outdrive, " B " should work. Hope this helps and would you mind letting me know if this info was correct? Thanks, WetWilly Here is the slightly "edited" version. Drive Unit Gear Ratio Identification All Bravo drive unit gear ratios are identified on each drive in two places: A The first place to look is on the decal on the port side of the drive housing.

It will have a number such as 1. B The second place to look will be on the universal joint splined yoke. It will be identified with a letter such as F. This method is explained in the following chart and is true for new or un-tampered with drive units.

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A drive unit could have had the gear ratio changed for high altitude, which would void out any application of the following chart. The gear ratio then would have to be determined by counting the teeth on the drive gear and the driven gear in the drive shaft housing and using the following chart for reference.

Last edited by WetWilly; at PM. Thank you WetWilly for this useful post!Read More since Since day one PPT has always been committed to providing our customers with the level of Technical Support they receive when shopping locally.

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alpha one lower unit gear ratio

These units differed greatly from previous years not only in design but also in that the flywheel housing on the engine changed at this point. This creates one of the big break points customers should be familiar with when inquiring about re-powering older boats.

Since the flywheel housing changed from toyou cannot couple a new engine to a pre sterndrive unit as the rear engine mount spacing differs on the new engine and therefore will not match to the old style inner transom plate. The other difficulty is that the newer 14 inch flywheel utilize a larger coupler that prevents re-using the old flywheel housing on the new engine. The Alpha Generation 2 models have been broken into several different Serial Number Ranges as follows:.

A very common question raised when replacing the Mercruiser Alpha sterndrives involves the gear ratio. NOTE: Mercruiser made the following gear ratio changes to the Alpha Model Sterndrives several years ago in effort to develop s stronger gear combination that would offer customers better overall Sterndrive durability. Be aware that these New Gear Ratios are a direct replacement for the older gear ratios.

There is no noticeable difference in performance. What was a 1. In Mercruiser introduced the 2. The Gen 2 drive has a substantially wider mounting dimension than the Gen 1. Figure 4 illustrates the overall size difference between the upper driveshaft housing. Although the mounting flange between the two drives will match the above mentioned difference prevent the two drives from being interchanged.

Other changes between the two include. The Alpha Gen II upper and lower housings are fastened together with two through bolts on either side of the drive along with the front and rear bolts, while the Gen 1 drives use one stud visible on either side.

Alpha Ones have two studs under the ventilation plate just above the prop. We are open and working our normal schedule. Mercruiser Alpha Generation 1 Vs. Mercruiser Alpha Generation 2 Sterndrive Comparison.

Other changes between the two include; The Alpha Gen II upper and lower housings are fastened together with two through bolts on either side of the drive along with the front and rear bolts, while the Gen 1 drives use one stud visible on either side. Buy the products and parts you need Buy Parts and Products.Even though our prices are the cheapest you will find, know that our products are not rebuilt!

They are aftermarket quality parts. With any Upper and Lower purchase, Sterndrive Replacement lets you benefit from our 3 year warranty, providing you with 3 years of full coverage. Only at Sterndrive Replacement. This Mercruiser sterndrives alpha one generation 1 unit is a replacement for HP and up from Standard Rotation 1. This is a replacement for Mercruiser sterndrives alpha one generation 1. Outdrive from HP. Sterndrive from HP. Mercruiser Sterndrive HP.

Replaces most Mercruiser sterndrives HP from Your Mercruiser sterndrive must have trim and tilt to be able to use our replacement drive. To determine if you have a counter rotation unit on your twin engine boat, it is easiest to look at the propellers. If your propellers are identical orientation, they are both standard rotation.

alpha one lower unit gear ratio

If the propeller blades are opposite, then the port side should be counter rotation. This applies to all inline 4-cylinders and inline 6-cylinders engines, up to and including Unit must have trim and tilt for replacement to work. If it has two trim hoses going to each cylinder, it has trim and tilt. Unit has an eyelet on top cover; replacement cover utilizes the new style flat top. Unit has a round cavitation plate on lower unit; replacement unit utilizes the newer style shift.

The replacement will be square. Gear ratio must be confirmed.

SEI Marine SE106 MerCruiser Alpha One Gen 1 Lower Unit (All Ratios)

To be safe, it is best to remove the top cover and count the teeth on the upper gears. Install Kit or Anode Kit not included. NO warranty over HP. Additional information Weight Related Products. Select options. Add to cart. Choose an option Standard Rotation 1.