Earlier this year the pump failed to "unload" for some reason since it was working very stellar when I bought this Sears pressure washer in 2012. Got enough free time to try and fix it so I can determine if I need to buy a new pump.
Unbolt the engine from the pump using a 6mm allen head socket and 1/2" wrench. Pull the engine up and the pump will slide out from the shaft.
Use the same 6mm allen to remove the head bolts.
To expose the pistons.
Plastic pieces removed.
Drain/fill plug for the pump oil. Best time to change the pump oil. Manual says it's a "sealed system". The fluid that came out says otherwise.
Oil that came out looked like MoS2 and metal shavings. Flushed crankcase with MMO and cheapo gear oil. Label says to use SAE W90 oil. Used some leftover RP 75W90 instead.
Head and crankcase block separated.
Breather/weep holes in the block.
Head assy:
Disassemble pump to find anything abnormal.
I'm assuming this is the unloader valve. Looks like a pressure adjust/bypass valve. The pin felt sticky moving in and out so it might be deposits. Tried soaking the parts in white vinegar.
Installation is the reversal of removal.
Tested it again and no dice. Taking a closer look at the pump head there are six plastic valves. Three large ones for the pistons the three small ones that are covered by the 14mm bolts. The engine still runs excellent with it's yearly OCI of Mobil 1 5W30 and E10 fuel with a dose of Techron or Regane fuel treatment so a new pump is in order.
...
Saw this earlier at Costco. Subaru powered pressure washer. Now you can have that straight pipe exhaust boxer engine sound to your pressure washer.
So I don't need to be driving around lugging a pickup bed and an additional 6' of chassis. I must've made the wrong vehicle choice then.
Unbolt the engine from the pump using a 6mm allen head socket and 1/2" wrench. Pull the engine up and the pump will slide out from the shaft.
Use the same 6mm allen to remove the head bolts.
To expose the pistons.
Plastic pieces removed.
Drain/fill plug for the pump oil. Best time to change the pump oil. Manual says it's a "sealed system". The fluid that came out says otherwise.
Oil that came out looked like MoS2 and metal shavings. Flushed crankcase with MMO and cheapo gear oil. Label says to use SAE W90 oil. Used some leftover RP 75W90 instead.
Head and crankcase block separated.
Breather/weep holes in the block.
Head assy:
Disassemble pump to find anything abnormal.
I'm assuming this is the unloader valve. Looks like a pressure adjust/bypass valve. The pin felt sticky moving in and out so it might be deposits. Tried soaking the parts in white vinegar.
Installation is the reversal of removal.
Tested it again and no dice. Taking a closer look at the pump head there are six plastic valves. Three large ones for the pistons the three small ones that are covered by the 14mm bolts. The engine still runs excellent with it's yearly OCI of Mobil 1 5W30 and E10 fuel with a dose of Techron or Regane fuel treatment so a new pump is in order.
...
Saw this earlier at Costco. Subaru powered pressure washer. Now you can have that straight pipe exhaust boxer engine sound to your pressure washer.
So I don't need to be driving around lugging a pickup bed and an additional 6' of chassis. I must've made the wrong vehicle choice then.
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