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2022 Update!

While a lot of what's written on this page covers the process by which Unique Diesel acquired Peninsular's engine line and some basic information about the engines, this page will also provide updates into the current status of this product line.

It doesn't take a lot of understanding of what's going on in the world to understand the state of the world economy and the challenges that a business would be subjected to. We purchased the Peninsular line in 2018 to continue to provide full parts support for the Peninsular engine line. While extremely challenging to establish supply chain and expertise with the product in a short time, we did manage it, including making products available world-wide through this online store you're viewing this message on today. To provide full parts support for this engine has been gradual, as there were areas that required new manufacturing sources to accomplish.

2022 Changes!

Before delving into the changes/limitations moving forward for this product line, it's important to understand the perspective in which these changes are coming from. With the 2020-2021 economic recession business did continue, but you'd be surprised to understand that even with less sales, the work associated with making those sales and business continuity was just as high as previous years. In short, being available and working full time for less.

The following changes will be implemented and in effect in 2022. Some are the results of the situations at play and some are the results of a change of focus and de-prioritization of this product line to allow this business to focus on other divisions to diversify into new areas.

2022 Customer Service

The time for a reply via email will increase from a day to 1-week turnaround for customer service inquires. This is because the business owner will no longer be part of the initial customer service functions, these functions are now handled by another party. This will change the results of customer service inquires from full-service to a non-technical customer service only. The intent will be to encourage customers to utilize the parts manual, and website information to self-service, and paid services if needed on demand. A reduction in customer service functions is necessary to better balance the work vs outcome ratio and allow the owner the much needed time to diversify the business.

2022 Engine Refurbishing Product Suspended

Due to supply chain shortages and unstable pricing for sub-components, the package refurbishing product will be suspended. This product was created to answer the continual questions from customers on how much it costs to rebuild a Peninsular engine. Unfortunately, our very high-quality approach to this (far superior that of the original Peninsular Engines company) wasn't well utilized. The decision to discontinue this is based on inability to guarantee production due to shortages and the non-impact of customer demand for the product. This may change, but refer to the applicable product for additional information.

2022 Manufactured Product Shortages

There are currently products that are on hold due to a lack of support from our previous manufacturing base. Some of our cast and machined products are currently undergoing duress as the long-term machinist discontinued support due to demand and change of business operations. This change has proven to cause tremendous complications. At present we are pursuing remedying this shortage, but will need persistent demands from customers wanting these goods (make customer service requests) and be willing to pre-purchase to invest in this becoming reality.

2022 New Paid Support Options

Technical support will have the option of an annual support program whereby full product support will be offered to customers enrolled in that product. This will enable rapid and continual technical questions to be answered in time of general maintenance and more complicated repairs. There will also be per-incident technical support options available as well as guidance service for selecting the parts needed for a repair. Take advantage of these services, because they also support the longevity of this business division. These services are the result of time is money, and in the past these things have been asked and utilized at the expense of time of the business with little to no compensation. We realize customers seek the manufacturer for information about these engines, but the reality of providing this has proven difficult and exhausting. Our primary focus always has been and will remain to just provide parts support not full engine support. This has been a complicated issue to resolve, and we will attempt to offer more digital services to better bridge this gap.

2018 The Business & The Division:

Unique Diesel - Marine

We are a small business that is greatly involved in the GM 6.2L and 6.5L Diesel engines from an enthusiasts perspective. Unique Diesel has been established as a business since 2007. Our formal resume would include publishing for thousands of enthusiasts posts online, drag racing with a 6.5L diesel, article on main authority "Page" about about most recorded and documented automotive rear wheel HP/TQ produced from a 6.5L that was upheld for years, and finally becoming an OEM in 2018 for a Marine Diesel platform.

Enthusiast -> Business -> Original Equipment Manufacturer (OEM)

In October of 2017 Peninsular Engines Inc. closed for business permanently. In January 2018 Unique Diesel purchased All assets of Peninsular Engines Inc. As of January 2018 Unique Diesel owns all intellectual, branding, and physical property from Peninsular Engines Inc. Unique Diesel took on the task to resume continued manufacturing, development, and parts supply chain for Peninsular Marine 6.2L & 6.5L series engines.

2018 Marked a very challenging year, timing was critical in securing the assets both in negotiation and symantecs of moving items and equipment from Michigan to Texas. We had just two-weeks to secure travel, package all contents and then prepare a full truck load (didn't even get it all) for safe travel to Texas before the rest of the remaining assets were destroyed. I hope the rest of the stuff doesn't mind living in the desert - joke.

Here is a 53' FTL trailer positioned in Michigan awaiting transport

After two weeks of personal strength and determination challenge with just a team of two we managed to secure many precious and irreplaceable items for transport to their new home in Texas. After just 3 weeks from signing business documents with the owner of Peninsular Engines we were presented with our next challenge, arrival of our new freight and future challenges and opportunities.

After arrival of the freight this determined business went public online to inform Peninsular customers seeking components that help was on the way. Taking on a nearly foreign product line is a challenge we won't ever forget and the hardships and victories we experienced in 2018-2019. Unique Diesel has worked hard to educate itself on the function, application, and repair of a Marine power plant in 2018. I always knew of this "marine" engine Peninsular had, but never took the time to study it before it was in my own hands, both interesting and intimidating at the same time, less of the latter now days. Talk about a crash course in things that float, with the only tires involved now are those on the trailer the delivers and sometimes retrieves the vessel. We still like 6.2 and 6.5 trucks though too.

Now it's 2020

The launch of is finally here, after manually quoting, selling, shipping and searching for parts by sourcing items we have finally documented enough components to provide these direct to the customer via an online store.

Many customers have had to endure some changes in getting components due to communication changes (phone to electronic email) and no online ordering website for numerous components, which has posed as a challenge. This was necessary due to the many things an OEM has to do with fixed resources to provide the very ambitious goals of supply.

Peninsular Marine Diesel Engine Serial Number Location

Peninsular Marine Diesel engines have been in production since 1984 through 2017 sold through Peninsular Diesel Inc. and Peninsular Engines Inc. Engines sold from 1984 - 1993 were 6.2L engines and were setup from 160HP NA and up to primarily 270 HP Turbo when turbocharged and aftercooled, with varying HP offerings in between. Engines sold from 1994 and on were 6.5L engines and were setup from 160HP NA up to 340 HP Turbo, with varying HP offerings in between.

Engine serial numbers are stamped near a bolt mounting pad on the left-hand side (starboard) of an engine when you are looking at the front of the engine (belts and crank pulley side). Like below.

The serial number pictured above is an example and this is the serial number you will need to refer to on your engine to decide what year model the engine is. This will not determine what the HP level of the engine is, because that information is usually stamped on the air intake adapter (90 degree aluminum adapter on intake manifold).

See our Tech section once logged-in as a verified customer for an information on decoding your serial number for determining the year of manufacture.

About Peninsular Marine Diesel Engines Durability

We often get asked about engine durability and repair-ability from those looking at a used boat. While this is a hard position to put us in asking this kind of question the information below should help some.

The first thing to keep in mind is that the Peninsular Diesel engine was engine based on a GM light duty diesel engine primarily used in vehicles for fuel economy. This engine was designed to be light in weight and fit into places where a SB Chevy or BB Chevy gasoline engine may. The 6.2 and 6.5L engines while very economical (both in price and fuel economy) are still light duty engines. Peninsular took this economical platform and made internal changes to the engine not found in other production versions of this engine that allowed it to be durable in increased power levels beyond the original engine's design limits. This was possible both because of internal modifications and external modifications for strength and that it was being run in marine with a great improvement in cooling capacity (automotive is greatly limited in this situation).

Average life span of one of these engines is 2500 Hrs, many greatly more with care. Which is double the life of the gas engines they replace. Many of the later edition versions of these engines 2001 and later were the most durable containing the updated blocks, and the latest versions in the last 7 or so years of production containing forged crankshafts.

Parts availability is good through Unique Diesel - Marine, care should be taken to acquire components listed here vs potentially compatible elsewhere as durable parts are not easily attainable in the aftermarket for this specific engine platform.

Parts Availability

Many vessels are equipped with the Engine Components Manual which is a manual that outlines and diagrams all the parts that can be ordered for an engine. To ensure you have the most current offering of part numbers we would recommend the purchase of the current manual, completely re-written for 2020. The older Engine Components Manuals from the 80's and 90's contain some obsolete part numbers (numbers that you won't find on the store, but actual parts that you will).

What if I have a part number that I cannot find in the store?

Start off with the 2020 Edition Engine Components Manual, use those numbers and part descriptions as keywords. Search the store by part number, then search by a normal name for the item, also look through the categories. If it's not available, contact us and provide the part number from the current manual, then we can point you to the right part. Other times it's because the part is not yet available on the store and we can make it available. Not all components in the manual are currently listed on the store. Many fasteners, clamps, and small accessories are not yet listed. Requests for these components makes them worth being listed, and we are happy to do so if needed. In conclusion, we have the parts, even if not listed on the store and can provide them. Another point of interest, there will be parts, tools, and documentation provided on the online store that will not be contained in the manual, so both the manual and this website will be your "tools" for repair, upgrade, and replacement of Peninsular Engines.

Engine Marinization Kits for 6.2L - 6.5L Diesels?

We do not sell a kit of parts to turn a regular 6.2 or 6.5 engine into a marine engine. There are a tremendous amount of components that are part of the marine engine assembly beyond the base longblock. Pricing the parts individually is also not an option. Using some used truck engine or non-marine longblock (yes, our base engine is very different) will certainly yield in an unreliable engine that will fail with short hours. We do not want our name (Or Peninsular's) name on some random custom crafted or economy build. Eventually the vessel that the engine combination is in will sell to someone else, who will then likely have a lot of problems and will assume it's our engine (a Peninsular), which is not good for the product reputation.

Another point, we are not capable of educating you how to assemble these parts onto an engine (and modify the engine). It's not an easy task and there are variations, for which someone attempting this would certainly have a lot of questions on how to do it. We are not interested and unwilling to guide this process. Just because we can do this ourselves does not mean we can or want to teach others. Obviously we cannot police parts sold, so parts purchased towards the goal of a kit will be completely unsupported, on your own.

Parts included on this website are for the repair of existing Peninsular engines only.

If new engine assemblies are unavailable, we recommend seeking out a used engine or pair real of Peninsular engines, at that point we could assist with parts for genuine serialized engines. We then also strongly recommend sending units back to us (the manufacturer) for refurbish and rebuilding as it's a complicated process involving techniques and steps and proper testing of components to make a reliable engine again. Owners and mechanics are strongly recommended at not attempting extensive rebuilding themselves.

Service Work

Finding mechanics that are familiar and work on these engines is not very common. Consider this in your evaluation of this engine. The engine is only as good as it's support. Current Diesel mechanics are only familiar with engines produced in the last 10 to 20 years maximum, this is due to the wear and tear these professionals face in working in boats. Working on marine engines is TWICE if not THREE times more difficult than working on Automotive engines.

The same can be said for gasoline engines produced during the time this engine was at it's peak production.

Bottom line, the support for parts from Unique Diesel - Marine is very good, extremely good when compared to other platforms this old. Many components are available, many that are backwards compatible with former generations of engines. The 6.2 marine and 6.5L marine engines are interchangeable in that a 6.2L marine engine can be replaced with a 6.5L marine engine with minimal changes. The same can be said for earlier 6.5L marine engines to current production 6.5L marine engine components.

We are working on programs and training for certified marine mechanics who are interested in working and helping us support this platform. If you are a certified marine mechanic, contact us to see the benefits we can offer to you for professionally supporting our engine.

Light Technical information found on TECH section:

There are some answers to frequently asked questions and some technical information present once you are logged into the store (does not show up when not logged in) under our TECH tab in the menu bar. Tech section contains information on decoding your engine serial number for manufacture date, among other details that will be updated as the needs arise. We are also working on creating documents for purchase that will illustrate types of repairs.

Technical Questions and Non-Sales information:

Being that all the engines in service were sold by Peninsular we (as a completely different business) we cannot provide free technical support and answer trouble shooting questions for owners. We do provide very basic product support for items we have sold. We do answer questions on a specific part's application if not clear on the store. We can also provide basic directly related information on how to install parts that you have purchased from Unique Diesel, but not prior to purchase.