Good morning all.

I recently bought a Kraft Stahl 3800 psi cold water washer with a 5.5. Hp 4 stroke engine and - with a set of exchangeable nozzles it went well for a few weeks. I did look for a source of advice/spares/etc. but it is Chinese and I hoped it would have a long life, - like so many items I have. I do have a very basic sheet, but it was second hand and pretty cheap.

To start it I have to tie a bit of string round the trigger, as it is not possible to pull the cord against a closed tap. I an not happy with this arrangement as the gun, - unless wedged somewhere tends to fly around squirting everything!

I was using it to clean out the troughing on a roof and came down the ladder after wedging it, but the string came undone and for some time it was running against the now-closed trigger. When I tried to continue I found that the pressure was now very low and un-useable. I thought maybe the inlet filter had got blocked as the motor was running fine and did not seem to be labouring, but it was all clean. The compressor is quite small and I am tempted to dismantle it all to see what has gone wrong. There is no chance of any warrantee either.

Has anyone had a similar problem, or got the exploded diagram or some form of manual, before I start undoing all the allen screws to get it apart. There is no sign of any input filter.

Any comments welcome as, apart from a few complaints, it has been a very useful addition to my equipment.

Thanks and regards George.

On 07/08/2013 10:15, George wrote:
Good morning all.

I recently bought a Kraft Stahl 3800 psi cold water washer with a
5.5. Hp 4 stroke engine and - with a set of exchangeable nozzles it
went well for a few weeks. I did look for a source of
advice/spares/etc. but it is Chinese and I hoped it would have a long
life, - like so many items I have. I do have a very basic sheet, but
it was second hand and pretty cheap.

It isn't 3,800 psi with a 5.5hp engine - unless they have found a way to
change the laws of psychics :-)

To start it I have to tie a bit of string round the trigger, as it is
not possible to pull the cord against a closed tap. I an not happy
with this arrangement as the gun, - unless wedged somewhere tends to
fly around squirting everything!

There should be an unloader/bypass valve to enable you to do that. May
be missing on a cheapo.

I was using it to clean out the troughing on a roof and came down the
ladder after wedging it, but the string came undone and for some time
it was running against the now-closed trigger. When I tried to
continue I found that the pressure was now very low and un-useable.

Depending on how long it was running with the trigger closed, it could
have seriously over heated & damaged the pump seals. Any makers name on
the pump? Or a photo?

I thought maybe the inlet filter had got blocked as the motor was
running fine and did not seem to be labouring, but it was all clean.
The compressor is quite small and I am tempted to dismantle it all to
see what has gone wrong. There is no chance of any warrantee either.

Doubt its the inlet, more likely the pump seals.

Has anyone had a similar problem, or got the exploded diagram or some
form of manual, before I start undoing all the allen screws to get it
apart. There is no sign of any input filter.

Any comments welcome as, apart from a few complaints, it has been a
very useful addition to my equipment.

Thanks and regards George.

Just looked online. The thing with the spring, above the inlet is the
bypass valve. Does that move in/out when the trigger is opened/closed?

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On 07/08/2013 18:46, The Medway Handyman wrote:

It isn't 3,800 psi with a 5.5hp engine - unless they have found a way to
change the laws of psychics :-)

Laws of psychics eh? If you concentrate hard enough it will work

But more seriously no reason why there needs to be a relationship
between power and pressure. If you think of the old simile that
pressure=voltage and flow=current - it's actually correct here.

1 volt at 1 coulomb per second (1 amp) equals 1 watt.

1 pascal at 1 cubic metre per second also equals one watt.

Of course 3800PSI is about 26 MILLION pascals, and 5.5HP is about 4Kw,
so you end up with a flow of about 1/6 of a litre per second if I have
the arithmetic right.

Andy

On 09/08/2013 00:29, Vir Campestris wrote:
On 07/08/2013 18:46, The Medway Handyman wrote:

It isn't 3,800 psi with a 5.5hp engine - unless they have found a way to
change the laws of psychics :-)

Laws of psychics eh? If you concentrate hard enough it will work

But more seriously no reason why there needs to be a relationship
between power and pressure. If you think of the old simile that
pressure=voltage and flow=current - it's actually correct here.

1 volt at 1 coulomb per second (1 amp) equals 1 watt.

1 pascal at 1 cubic metre per second also equals one watt.

Of course 3800PSI is about 26 MILLION pascals, and 5.5HP is about 4Kw,
so you end up with a flow of about 1/6 of a litre per second if I have
the arithmetic right.

Andy

In the trade, they use a simple calculation to compare the cleaning
effect of different machines;

Cleaning Effect = Pressure (bar) x Flow (litres/min) / 600

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On Wednesday, 7 August 2013 10:15:41 UTC+1, George wrote:
Good morning all.



I recently bought a Kraft Stahl 3800 psi cold water washer with a 5.5. Hp 4 stroke engine and - with a set of exchangeable nozzles it went well for a few weeks. I did look for a source of advice/spares/etc. but it is Chinese and I hoped it would have a long life, - like so many items I have. I do have a very basic sheet, but it was second hand and pretty cheap.



To start it I have to tie a bit of string round the trigger, as it is not possible to pull the cord against a closed tap. I an not happy with this arrangement as the gun, - unless wedged somewhere tends to fly around squirting everything!



I was using it to clean out the troughing on a roof and came down the ladder after wedging it, but the string came undone and for some time it was running against the now-closed trigger. When I tried to continue I found that the pressure was now very low and un-useable. I thought maybe the inlet filter had got blocked as the motor was running fine and did not seem to be labouring, but it was all clean. The compressor is quite small and I am tempted to dismantle it all to see what has gone wrong. There is no chance of any warrantee either.



Has anyone had a similar problem, or got the exploded diagram or some form of manual, before I start undoing all the allen screws to get it apart. There is no sign of any input filter.



Any comments welcome as, apart from a few complaints, it has been a very useful addition to my equipment.



Thanks and regards George.

Thanks Dave, I have taken some photos of it, but it will take a day or so to post them on my website, can I put them here? If so I don't know how. You do mention that you looked it up on the web. That is what I was trying to do! I could not find it however. If you can show me where it is, I would be most grateful. It was not pushing against the closed tap for more than a minute or two and it was not labouring or overheating as far as I could see.

Regards George.

On 11/08/2013 20:51, George wrote:
On Wednesday, 7 August 2013 10:15:41 UTC+1, George wrote:
Good morning all.



I recently bought a Kraft Stahl 3800 psi cold water washer with a 5.5. Hp 4 stroke engine and - with a set of exchangeable nozzles it went well for a few weeks. I did look for a source of advice/spares/etc. but it is Chinese and I hoped it would have a long life, - like so many items I have. I do have a very basic sheet, but it was second hand and pretty cheap.



To start it I have to tie a bit of string round the trigger, as it is not possible to pull the cord against a closed tap. I an not happy with this arrangement as the gun, - unless wedged somewhere tends to fly around squirting everything!



I was using it to clean out the troughing on a roof and came down the ladder after wedging it, but the string came undone and for some time it was running against the now-closed trigger. When I tried to continue I found that the pressure was now very low and un-useable. I thought maybe the inlet filter had got blocked as the motor was running fine and did not seem to be labouring, but it was all clean. The compressor is quite small and I am tempted to dismantle it all to see what has gone wrong. There is no chance of any warrantee either.



Has anyone had a similar problem, or got the exploded diagram or some form of manual, before I start undoing all the allen screws to get it apart. There is no sign of any input filter.



Any comments welcome as, apart from a few complaints, it has been a very useful addition to my equipment.



Thanks and regards George.

Thanks Dave, I have taken some photos of it, but it will take a day or so to post them on my website, can I put them here? If so I don't know how. You do mention that you looked it up on the web. That is what I was trying to do! I could not find it however. If you can show me where it is, I would be most grateful. It was not pushing against the closed tap for more than a minute or two and it was not labouring or overheating as far as I could see.

Regards George.

They sell them on flea bay, only saw a picture.



--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On Monday, 12 August 2013 18:35:36 UTC+1, The Medway Handyman wrote:
On 11/08/2013 20:51, George wrote:

On Wednesday, 7 August 2013 10:15:41 UTC+1, George wrote:

Good morning all.






I recently bought a Kraft Stahl 3800 psi cold water washer with a 5.5.. Hp 4 stroke engine and - with a set of exchangeable nozzles it went well for a few weeks. I did look for a source of advice/spares/etc. but it is Chinese and I hoped it would have a long life, - like so many items I have. I do have a very basic sheet, but it was second hand and pretty cheap.







To start it I have to tie a bit of string round the trigger, as it is not possible to pull the cord against a closed tap. I an not happy with this arrangement as the gun, - unless wedged somewhere tends to fly around squirting everything!







I was using it to clean out the troughing on a roof and came down the ladder after wedging it, but the string came undone and for some time it was running against the now-closed trigger. When I tried to continue I found that the pressure was now very low and un-useable. I thought maybe the inlet filter had got blocked as the motor was running fine and did not seem to be labouring, but it was all clean. The compressor is quite small and I am tempted to dismantle it all to see what has gone wrong. There is no chance of any warrantee either.







Has anyone had a similar problem, or got the exploded diagram or some form of manual, before I start undoing all the allen screws to get it apart.. There is no sign of any input filter.







Any comments welcome as, apart from a few complaints, it has been a very useful addition to my equipment.







Thanks and regards George.



Thanks Dave, I have taken some photos of it, but it will take a day or so to post them on my website, can I put them here? If so I don't know how. You do mention that you looked it up on the web. That is what I was trying to do! I could not find it however. If you can show me where it is, I would be most grateful. It was not pushing against the closed tap for more than a minute or two and it was not labouring or overheating as far as I could see.



Regards George.



They sell them on flea bay, only saw a picture.







--

Dave - The Medway Handyman www.medwayhandyman.co.uk

Well I took the top off the end of the pump leaving the swash plate pistons behind and in the valve cover I found that one of the incredibly delicate plastic assemblies, - sprung loaded, had broken up, - the one nearest the inlet pipe. It will be impossible to repair this without the correct kit as they are tiny and look quite unsuitable for the job. It may have been the vibration of bubbles going through the pump that caused this disintegration. Unless I can contact Kraft Stahl, I think it is a write off. What a shame. No identity or anything on the pump, at all.

Regards George.