What kinda oil does the Landa PG4-3500 take

Check out the trigger mechanism. Water should come out at any time, even when you do not have the unit started.

http://engines.honda.com/company/faq Both of your questions and many more are answered by Honda here
People usually use synthetic oil in cars to be able to go more miles between changes. Honda says to keep the same change intervals even with synthetic oil. Seems like pouring money down the drain to me.

to get this answer it is simple , google landa pressure washers then look for your model number and that shall tell you the exact oil you need

check inlet strainer for restriction also check valve may be obstructed there r 6 total behind the hex plug on pump head

The Honda engine will use standard 30W. the pump will use 30W non-detergent.

Sincerely,
Aron Kerr
Landa Northwest
www.landanw.com

The engine will use standard 30W motor oil. The pump will use 30W non-detergent oil.

Sincerely,
Aron Kerr
Landa Northwest
www.landanw.com

A loss of pressure on this type of washer is normally caused by failing water seals and check valves in the pump. You will need to replace both of these using a pump rebuild kit that will be available by contacting the manufacturer of your machine. The pump oil used will be 30W non-detergent.

Sincerely,
Aron Kerr
Landa Northwest
www.landanw.com

you can use sae 30 in the motor and hydraulic oil or gear oil in the pump.
just note that there may be two oil filler holes on the motor.

Landa does not have a model HMP so I am not sure which machine you have. If you can provide a full model and serial off of the model tag on the machine I can provide you with a digital copy of the manual you are looking for.

Sincerely,
Aron Kerr
Landa Northwest
www.landanw.com
800.247.8103
503.255.6508

send them an email at [email protected] or contact them directly at 800-526-3248 for more info specific to your model which was not listed above. hope this helps you