Marine diesel and engine surveys
The engine survey a hull survey leaves out
Most marine surveys report on machinery only as far as it is visible, then refer the engines to a mechanic. I am the mechanic, and I am a mechanical marine surveyor. Compression, load testing and lab analysis, in one written report.
- In business
- Since 2017
- In marine diesel
- 20 years
- Factory certified
- Volvo Penta
- Travel service
- FL to Caicos
Request a survey or service
Tell me about the boat
The fastest route is the phone. Send this and it lands in my inbox, or call (941) 780-1330 and describe the symptom.
What I do
Two jobs, one set of hands
Surveys for people deciding whether to buy a boat, and service and repair for people who already own one. Both draw on the same 20 years inside marine diesels.
Mechanical Marine Surveys
A documented condition report on your propulsion engines and generator, from visual inspection through sea trial.
02 / SurveysPre-Purchase Engine Survey
The engine half of your buyer's due diligence, documented before you sign and priced against the repairs it finds.
03 / RepairDiesel Repair
Engine, transmission and generator service on marine diesels, from routine maintenance through a complete repower.
04 / SystemsMarine Generator Service
Service, repair and load testing for marine generators, the system that keeps air conditioning and power alive at anchor.
05 / RepairEngine Repower
Replacing tired engines with new power, including the mounts, controls, exhaust and propeller match that make it work.
06 / RepairEmergency and Dockside Service
Mobile response to your slip or the yard when the boat will not start, overheats or fails before a trip.
Findings from real surveys
This is what you are actually buying
Every finding gets photographed, coded and explained in the written report. These are from jobs I have done. Not one of them was visible from the dock.
Starboard turbo blades damaged
Compressor wheel damage found on inspection. This is the kind of finding that changes a purchase price, and it is not visible from the dock or in a general hull survey.
Generator exhaust elbow badly rusting
Internal corrosion on a generator exhaust elbow. Left alone, a perforated elbow admits sea water into the unit, which is a far larger bill than the part.
Port engine oil cooler leaking
A leaking oil cooler lets coolant or raw water reach the oil, which damages bearings. Caught on survey, it is a repair. Caught later, it is an engine.
Hose clamp condition noted
Small items get photographed and coded too. A clamp is a few dollars, and a hose that lets go below the waterline is not a few dollars.
A mechanical marine survey from Jon Diesel Marine includes a compression reading on every cylinder, a wide open throttle test, a sea trial under load, and laboratory analysis of engine oil, coolant and transmission fluid, delivered as one photographed written report.
Who turns up
Twenty years, one pair of hands
I was born and raised in the Sarasota and Bradenton area and started on marine diesels at eighteen. Three years at a mobile marine outfit on early model engines, seven years maintaining yachts and their systems, then six years at a Volvo Penta dealer where I got certified and began performing engine surveys.
I started Jon Diesel LLC in 2017 to do that work on my own terms. When you book, I am who arrives. There is no rotating crew and no service writer between you and the person holding the wrench.
Customer review
What one long standing customer said
I have had the pleasure of having Jon service my Formula 400SS with twin Volvo diesel D6 400 HP engines for the last several years and I can tell you first hand Jon is awesome. His work is professional, his character is impeccable, his pricing is reasonable. What more can I say about Jon? He is amazing. 5 big stars all the way. A guy you can always trust and count on.
Where I work
Mobile service across the Suncoast
Based in Myakka City, covering Manatee, Sarasota and Charlotte counties, with travel work throughout Florida and the islands.
Questions people ask before they call
What is the difference between a hull survey and an engine survey?
A general marine survey covers hull, structure, electrical, plumbing and safety gear, and normally reports on machinery only as far as it is visible. An engine survey is the mechanical examination: compression on every cylinder, engine management data, load testing and laboratory fluid analysis. On a diesel powered boat they are two separate jobs, and the engine survey is where the largest hidden numbers turn up.
Do you come to the boat?
Yes. This is a mobile service with no walk in shop. Work happens at your slip, on a private lift or in the yard, across Sarasota and Manatee counties and further when a job calls for it.
How much does a marine engine survey cost?
It depends on the number of engines, their size and accessibility, whether a generator is included and where the boat is lying. Call with those details and you will get a straight figure rather than a range that means nothing.
What engines do you work on?
I am Volvo Penta certified and spent six years at a Volvo dealer, and across 20 years I have worked on nearly every make of marine diesel, from small auxiliaries to yacht propulsion pairs and generators.
How far do you travel?
Sarasota and Manatee counties are the core service area, extending to Charlotte County and St. Petersburg. I have worked throughout Florida and travelled to the Bahamas and Turks and Caicos for jobs that warranted it.
Can you help if my boat has broken down?
Call and describe what happened and what it is doing now. Emergency and dockside calls are taken outside posted hours. Shut down an engine that is overheating or alarming rather than restarting it repeatedly, because that turns small failures into large ones.
Tell me what the engine is doing
Describe the symptom on the phone and most of the time the problem is narrowed before I arrive. Surveys are booked around your sea trial date.