If you are in the market to purchase a used Jetski then it’s important to check over the whole personal watercraft. In this article, we will go over the top 20 things to check before making your purchase. This is to make sure you are not in for some nasty surprises.
There are 3 main manufacturers of PWC out there in the market today and all have similar technologies to provide power and stability to the Jetski. They are:
- Yamaha Waverunners
- BRP Sea-Doo
- Kawasaki Jetski
- There are other older manufacturers like Honda and Polaris but you don’t see them much anymore.
I like the design and reliability of BRP Sea-Doo so most of the instructions here will be for these Jetskis. Although you can apply these checks for all of the watercraft out on the market today.
Table of Contents
Questions to ask when buying a used
- How many runtime hours on the clock?
- Freshwater or saltwater use?
- Is the Jetski registered?
- Is the trailer registered?
- Does the hull number match the registration papers? USA Check Data Tag numbers and paperwork match the name on the documents for the relevant state. For the UK boat owners be sure to check over the registration papers and BSS certificate. (Boat Safety Scheme)
- Are there any repairs or modifications?
- When was the last service? When was the last Jetski oil change done?
- When did you last replace the Jetski spark plugs?
- Who does your servicing?
- Do you have spare keys?
- Is there any safety equipment included in the sale price such as life jackets and an anchor?
- If purchasing from a dealer is there any warranty?
Mechanical Checks to do before purchasing a used Jetski
Always check over the PWC yourself or ask someone with some mechanical knowledge to do it for you. The following points are easy to do yourself to check for common jet ski problems.
1. Ask if you can see or test the ski if purchasing online. Check over the hull for any puncture holes, scratches or marks. Holes in the gel coat can cause osmosis over time which can weaken the fiberglass. Make sure to repair any holes in the hull before use.
2. Take off the seat and look inside the engine compartment for leaks. This may include exhaust cylinder head, exhaust system, fuel system, oil leakages, and water ingress. This is what to look for when buying a used Jet Ski.
A well-maintained engine should have a light anti-rust oil covering on it from a spray can such as
Check the engine oil to see if it is black or dirty. This could also indicate a Jet-Ski engine that was not maintained very well.
3. Look at and check the steering mechanism, it should be smooth and quiet. What is the condition of the handle grips?
4. Is it a premix 2 stroke engine (oil mixed with gas/petrol) or is it a 4 stroke engine? Nowadays most larger 2 and 3 person jetskis have 4 stroke engines which are very reliable.
Older 2 stroke jet skis can be unreliable and parts are getting harder to find. Many repair shops are now refusing to work on them because of the low spare parts issue.
5. If the PWC has been used mostly in saltwater there may be excessive rust present. If yes this will reflect in the overall condition and price.
6. Check the engine mounts to see if any are broken. If some are broken the engine may now be out of alignment.
7. Take it to a repair shop to do a compression test report (unless you have the tools to do this yourself). This will test the piston/bore condition. If a cylinder has low compression it could have worn piston rings and will need to be repaired. Best to walk away unless its a very good deal. The numbers should be within 10% of each other.
8. If it is an ex-rental Jetski it will have a large number of run hours and usually will be in very poor condition. These jet skis will sit in the water all day long and when they are being ridden they will be thrashed around. Usually, they are being sold because of the expense to keep them running is getting expensive. Best to look elsewhere for a used Jet-Ski unless it is a very good deal.
9. Use a torch or a phone camera to look into the water inlet grate. Check the impeller condition and the condition of the pump seal also called the wear ring. There should only be a 1-2mm gap between the impeller and the wear ring seal. Any larger gap and the jet pressure will be lower and cavitation could happen, resulting in low speeds.
10. Check the trailer winch for rust and fraying cables or webbing. To check the wheel bearings grab old of the trailer wheel and rock it from side to site. It shouldn’t wobble. If it does it could indicate worn wheel bearings. If it has a Bearing Buddy system check if it is leaking. You should learn how to grease a bearing buddy and maintain it.
11. If you can, hook the personal watercraft trailer up to a vehicle and check the conditions of the trailer lights and indicators. There shouldn’t be any water in these fittings.
12. Hook the Jetki to a water hosepipe and start the motor. Turn on the hose tap water. Check for excessive smoke from the engine.
Subsequently, if you haven’t started up your jet-ski for a while there may be some initial smoke, but it should clear up within 1 minute.
Look in the engine bay for any water leakage from the cooling system. Most Sea-Doo Jetskis use an internal cooling fluid system to cool the engine. This fluid needs replacing every few years. It’s an easy job to replace this cooling fluid yourself on a Sea-Doo.
13. On Sea-Doo Jetskis check the carbon seal by lifting up the rubber flap. This seal should be clean and not have any stress fractures on it. Look for excessive or uneven wear. Excess carbon dust in the hull could indicate a problem. A small line of carbon dust on the inside base of the hull will be fine and is normal.
14. How old is the PWC battery? Most Jetski batteries will only last 3-4 years due to all the pounding they take. Therefore, if the battery is 4 years or more old, then factor in a replacement cost of around $100 plus labor. It is an easy procedure to replace your Sea-Doo battery so you can do this yourself.
15. Check the condition of the feet floor mats. If they are badly worn they will have to be replaced for the safety of the rider. You can replace these Jetski floor mats yourself by following this procedure.
16. Check the tow hitch condition if it has been stretched or pulled out of the fiberglass.
17. If there is a bilge pump check that it is working by using the override switch.
18. Some high-end personal watercraft have added superchargers so be sure to factor in servicing on these parts every 100 hours or so. A bad supercharger can destroy an engine if it fails. Be aware that some Sea-doo PWC may still have the old ceramic washers in the superchargers. If this is the case, get them changed out to new metal ones as soon as possible.
Sea-doo superchargers came with ceramic clutch washers from 2004 up to 2007.
If the ceramic washers fail, they will fill your motor up with ceramic particles. Not good.
19. Operate the revere drop down gate. On Yamaha’s, this will be a manual pull leaver whereas Sea-doo uses an electric motor. Both should move fast and without jamming or binding. They can be damaged if the PWC reverses into a solid object. Many people fail to check the reverse lever when buying their first Jet-Ski.
20. Open the front compartment and look for cracks on the hinge. How clean is the front compartment? Look for signs of damage from a metal anchor that could have been bouncing around in there.
21. Is there a Jet ski automatic bilge pump fitted? If there is, test it out with the manual bilge test switch. If it is an automatic bilge pump only remove the pump from the base of the Jet ski and put it in a bucket of water to see if it starts.
Jetski test ride checks
If you get a chance to have a test ride before buying a Jet-ski it is important to check a few items out for your peace of mind.
On your first run take it nice and slow and check out the steering and acceleration. It all should be smooth at various speeds. Acceleration should be instant at the touch of the throttle.
Be aware that newer Sea-Doos have different user modes of riding such as Normal, Sports, Eco and Learner. That is to say, each of these modes will have different acceleration curves with the learner mode also restricting the top end speed.
You will be able to select between the three different modes by pressing the ECO/Sports button for a few seconds.
Run the Jet-Ski up to full speed and make sure there is no unusual noises or excessive smoke. Some personal watercraft will travel nice and level at top speeds whereas some will constantly bounce around. This is normal.
Come to a complete stop and try the reverse feature. Some Jet-skis will have a handle to pull like the Yamaha’s, whereas the Sea-Doo’s will have an electronic activated motor. The left-hand trigger on the handlebars will put the PWC into reverse.
Best time to buy a jet-ski
Usually, the end of the
Winter also means the new models will be coming out for the following year so you can often pick up some real bargains on demonstration models. Don’t be afraid to ask for a better deal as there is often a lot of wiggle room in MSRP prices (Manufacturer’s Suggested Retail Price)
If you find something wrong with a used Jet-ski ask for a discount to get it repaired. If they don’t want to budge then move on for a better deal. There will be a better offer just around the corner.
What to do after purchasing a used Jetski
After purchasing a used jet-ski from a dealer or privately be sure to change over the user registration details on the PWC and the trailer as soon as possible. However, if you need to replace the hull numbers and decals be sure to use some heat so the numbers come off easy.
I like to also give the Jet-Ski a full service just so I know where I am at with the servicing. This means an oil change, new oil filter, coolant flush, and a new set of spark plugs. Get yourself a good repair manual so you can save some money and do all the servicing and repairs yourself.
The only way to remove the oil from a Sea-Doo is to suck it out using a hand vacuum pump using the dipstick hole. It is a handy item to own as you can also change other fluids in your car as well.
If you follow these tips you will have all the basic knowledge on what to look for when buying a used jet ski. Most importantly, you won’t get ripped off and you can make informed decisions on a very expensive but fun watercraft.
4 Stroke jet skis are very reliable but when they fail it can be very expensive to repair. As long as you have them serviced yearly or at the regular service intervals, you should have trouble free running.
Take the time to read over your user manual and be familiar with how to winterize your Sea-Doo or Yamaha Jetski.
Let me know in the comments below wha to look for when purchasing a used Jet-ski.
I am a qualified Industrial Electrician for the past 20 years and I love to share my knowledge on home repair jobs.
I love fast toys like Motorcycles, Cars, Jetskis, and Boats so writing about them is easy.
To keeps costs down I do all my own mods, repairs, and servicing. These skills I want to share with everyone. DIY is a skill everyone can learn.