Kew Hobby 88 Pressure Washer Fault Diagnosis

[Sparks]

A pressure washer I used has this same problem, pulsating output.

It was the dump valve (It is supposed to dump the high pressure side back to the low pressure side when you stop the output) but when you open the output agin, the valve is supposed to stay shut; it wasn't staying shut due to some crap in it.

Also, i had the same problem when the lance was partially blocked, the unit ramped up to too higher pressure, the dump valve operated, the pressure then dropped as the output was actually open, and then it just cycles like this. (In my unit, taking off the nozzle at the end resulted in water spraying out of 4 holes in the side, and one in the end - the one in the end was clogged with crap, clearing this cleared the fault.

Sparks...

[Gelf]

I bought this at the car bootie last year. I guess it's a bit long in the tooth, but it seems substantially built. Naturally, it doesn't work properly (always the way!) The pump runs but the water comes out in rapid pulsating spurts and the pressure gauge fluctuates from zero to about 1/4 way round. Any suggestions of likely fault before I strip it down and likelyhood and source of any spares that may be needed? TIA Gelf

[Magician]

Sparks

You are dead right in your diagnosis, although I'd check the nozzle first!

Worth the effort, the KEW 88 is a legend amongst domestic pressure washers.

Spares should be available. KEW is now called Alto and they are in Penrith, Cumbria.

Dave

[Dave Liquorice]

Ooo, useful snippet. Sort of in the market for a pressure washer and was probably going for a karcher if only beacuse of the market penetration and bright colour.

But if Kew/Alto are in Penrith and they are still thought of as a good buy that is a whole new ball game. Penrith is just 20 miles away, lot better than trying to get to Germany...

[Peter Parry]

Quite often caused by insufficient inlet pressure or the presence of a pressure limiting valve on the mains supply side. Try putting a bucket of water about 4ft above the ground and taking a short length of hose from that to the washer. If it works OK it is poor water feed causing the problem.

[Magician]

Hi Peter

a pressure limiting valve on the mains supply side.

Could be. On that point, avoid the hozelock 'auto stop' connectors with pressure cleaners. These have a valve inside so you can disconnect the fitting without turning the water off.

The suction from the pump often causes the valve to operate and restrict the water supply.

Dave

[Magician]

Dave wrote; Ooo, useful snippet

Nilfisk-ALTO Division of Nilfisk-Advance Ltd. Bowerbank Way Gilwilly Industrial Estate UK-Penrith, Cumbria CA 11 9BQ

Tel.: [phone] Fax: [phone] E-mail: [e-mail]

[The Wanderer]

Got the same washer (I think), and yes it's (very) long in the tooth. I'm guessing mine is 20+ years old.

Had exactly this problem, and it still crops up from time to time. It's invariably a smallish bit of grit in the outlet lance, keeps blocking the nozzle. Bit of a pig to clean out, I've found setting the lance to the low pressure setting and 'jet' rather than fan spray so you can dribble some water down through the nozzle, combined with some repeated tapping onto a block of wood (don't damage the pipe & seal at the other end) will dislodge the grit.

Don't try removing the nozzle. I tried it, buggered the 'fan' spray deflectors and finished up buying a new spray lance complete. Quite pricey.

[Magician]

The Wanderer wrote;

invariably a smallish bit of grit in the outlet lance, keeps blocking the nozzle. Bit of a pig to clean out

[Martin Evans]

I hope they have a better policy on spares pricing than they had 10 years ago. Not long out of guarantee a motor burned out on a 340 quid unit. They offered a new motor at 270 quid or a 'reconditioned' pressure washer on exchange with 3 months guarantee at 290 quid.

Needless to say I declined so I ground the weld out and split the motor casing, pulled the armature and had it rewound for 20 quid. A

15 quid weld job later (on stainless) and it was as good as new.

[Gelf]

[op]: thanks for all your helpful replies. It looks like it's worth saving. I think I'll start with the dump valve - it looks favourite for me Gelf

[Daniel]

Hi Martin, I have a Hobby 88 thats only producing 20 bar pressure. Did you take photos of the pump with the casing split open as I will be very interested to see what the innards look like.. Thanks

[Andrew]

17 years later, .....

[Brian Gaff]

Yes it will be in landfill by now. Brian