The pre-2017 carbureted engines have no cradle — they lift straight up on mounts below the engine, so the couplings have to come off first. They also carry two parts JetSurf later deleted: a crankcase drain valve and a vacuum bilge pump. This is the whole job, out and back in, running.
Which engine this is — 0:51
0:56 — Older fuel tank + breather (breather on the front of the tank, not a valve in the back).
1:02 — No engine cradle — small mounts below the engine; it lifts straight up.
1:16 — These engines ran to ~2017, then the longer cradle, then ~2019 fuel injection.
Remove the fuel tank — 1:28
1:35 — Remove the front breather, the fuel line, and the Velcro strap.
1:50 — Lift the tank and twist it out around the engine-hood bracket (use the cavity to clear the bracket).
Undo the couplings — 2:08
2:30 — Undo the little clamp on the back (two-piece — it sits against the coupling), then the coupling itself.
2:58 — Turn the coupling round and spread it with a screwdriver so it slides off the shaft. Pop the screwdriver back out.
3:16 — Under there are the drive-shaft cush drives / buffers — inspect them off the board later.
Disconnect the wiring — 3:28
3:48 — Disconnect the starter-motor plug — hook a finger under (push it in first if needed). If it's really tight, ease it with a screwdriver behind the tag — carefully, the tag snaps.
4:23 — Disconnect the timing-sensor plug below it (same clip). Take the key off; put the little screws back in their holes for next time.
4:58 — Take the other coupling off. Tip: when refitting couplings with the longer screws, make sure they can't touch the gears underneath — that's catastrophic.
5:42 — Slip the bilge-pump wire clear. Pull the exhaust cooling line off.
Cooling & telltale lines — 6:02
6:06 — The jet-pump cooling line has a snap-ring fitting — pull the ring back with two fingers and slide the tube out.
6:33 — Same for the telltale tube — push the ring back, pull it out.
Engine mounts — including the slotted one — 6:45
6:47 — Undo the engine mounts — 8 mm bolts.
7:13 — One mount has a little earth wire — newer models don't, but leave it (it's there for a reason). Remove the earth lead.
7:34 — The awkward one is the mount bolt under the exhaust port — a small 8 mm ratchet spanner, worked from the other side.
8:11 — That bolt doesn't have to come right out — the bracket has a slot, so once loose it slides up the exhaust port and the engine lifts free of it.
Make room & the old-school extras — 8:34
8:41 — Roll the engine on its side and remove the spark plug for clearance (it's a tight squeeze). Check the plug — but fit a new one on any rebuild.
9:08 — Remove the vent tube from the crankcase drain valve (it runs off a nipple on the crank). This valve lets you drain a flooded crankcase — an old jet-ski idea, deleted on new boards. Remember to refit it — off, the engine draws air and runs badly.
9:45 — Note the secondary vacuum bilge pump — a crankcase-pulse diaphragm pump with two one-way valves that pumps water out the second telltale (that's why these boards have two telltales). Deleted on new boards.
Throttle cable & lift out — 10:36
10:58 — Free the throttle cable under its clamp.
11:14 — Squeeze the little ball-and-socket end off with long-nose pliers. The engine is out.
Reinstall — couplings & cooling first — 11:31
11:37 — Clean the engine bay of sand and muck. The coupling drive rubbers were fine — reuse; slide them back on.
11:54 — Hook up the hard-to-reach hose first, then fit the telltale tube — get it tight. Off, it's a massive crankcase air leak and the board runs terribly.
Route the throttle cable — 12:39
13:05 — Route the cable through the board before the engine goes in — it saves a lot of mucking around.
13:12 — Note the two washers on the bottom of the crank — they keep the cable out of the starter gear.
13:34 — Fit the cable to the carb mount, then pull it back through: under the tube, under the two washers, above the cylinder outlet, into the cylinder.
14:07 — Set the free play: adjust for a little free play with full throttle available, smooth operation. Don't overtighten — it pinches and jams the cable (Rod demos this).
New exhaust rubber & engine in — 15:14
15:14 — Fit a new exhaust seal rubber every time the engine's out — the old ones fog out and get oil-contaminated.
15:44 — Spray the rubber, lift the exhaust and engine in. Start all three mount bolts loose — the mount under the exhaust port is last (the others help align it).
16:59 — Before tightening anything, fit the coupling — slide it home; the shaft is what aligns the engine. Then tighten the coupling and collar (two bolts opposed for balance) and the retainer.
18:03 — Tighten the engine mounts. On the loose bolt, put finger pressure on it so the ratchet bites instead of slipping.
Cooling lines, wiring & spark plug — 19:19
19:22 — Cooling lines are the priority — a new engine run without them is an instant meltdown. Push the quick-release couplings home; if you can't pull them out without pressing the ring, they're locked. Tube to the cylinder, tube to the telltale, cable-tie both.
20:39 — Reconnect the wiring — timing sensor + cover, earth lead, breather, starter-motor plug (push until it clicks), starter rest lead.
22:50 — Fit the spark plug. Fit the plug cap, then flip the retaining spring over its end — a new spring is stiff; check the cap seats against the shoulder.
Fuel tank, prime & start — 23:43
23:49 — Fit the fuel tank — keep the back strap in hand or it gets lost inside. Strap it, breather up, seat it, fuel line on.
24:59 — Prime a dry carb: use the syringe that came with older boards (originally the clutch oiler) — draw fuel from the tank and squirt it straight into the carburettor. Repeat 2–3 times.
25:37 — ICU on (red light flashes), key in — it fires. Don't over-prime — too much fuel floods it (it half-catches then dies). A little less than you think.
Tune the carb — 26:52
26:59 — Factory mixture settings for this carb: high speed 1¾ turns out, low speed 1¼ turns out. Set to factory, then adjust on the water.
27:13 — Idle was way too high — special spanner, crack the lock nut, back the idle screw off a touch.
27:38 — Restart with the hose on, set the idle, lock the idle screw off.
Tip: the old-school engine lifts straight up, so the sequence is couplings off → wiring → cooling lines → mounts (slot the exhaust-port one) → drain-valve vent tube → throttle ball end. Reverse it, and always fit the coupling before you torque the mounts — the shaft sets the alignment.
Caution: refit the crankcase-drain vent tube and get the telltale tube tight — either one loose is a crankcase air leak that makes the board run badly. Fit a new exhaust seal rubber and a new spark plug on any rebuild. Never run the engine without the cooling lines connected, even for a second.
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