June is the month when your phone shouldn’t stop ringing. Quotes coming in faster than you can write them, customers asking if you can get there by the weekend, crews running ten hour days. It’s also the month a stuck unloader or a milky pump turns what was supposed to be a $1,200 day into a card charge and a half-day shop visit... no one wants that.
If you’ve been running the same rig since March without giving it a real once-over, this week is the one. You’ve got a few quiet days before the calendar fills up. Here are the five checks worth doing now — what to look at, what it costs you when it fails mid-job, and what to swap if you find something.
1. Pump oil
First and least glamorous. Pull the dipstick or look through the sight glass on the pump. You’re looking for two things: the level, and the color.
Clean pump oil is honey-colored. Milky, coffee-with-cream oil means water got past a seal and the oil is emulsified. Run it like that and you’re looking at scored pistons inside of a season. Dark and gritty means it’s just past due.
Industry baseline: change pump oil after the first 50 hours, then every 100 hours or every 3 months — whichever comes first. If you store the rig wet over winter, pretend it’s been 3 months even if the hour meter says otherwise.
If the oil is milky, replace the seals before you swap the oil — otherwise you’ll be doing this again in two weeks. Most contractors can pull seals in 30–40 minutes once they’ve done it twice.
Have a spare quart of pump oil and a seal kit on the trailer all summer. The seal kit lives in the toolbox for $25 and saves a $400 service call.
2. Unloader valve
If your gauge is bouncing, your trigger has a delay, or pressure surges when you shoot the wand, the unloader is talking to you. Ignore it now and you’ll be standing in someone’s driveway with a customer watching you not clean their concrete.
Pull the unloader, inspect the seat, and check the spring. Mineral buildup on the seat shows up as a chalky ring — clean it with a soft brass brush. A weak spring shows up as inconsistent pressure with no obvious cause. Spring kits and rebuild kits run $20–$60 depending on the brand.
If you’ve been swapping tips constantly to chase the right pressure, that’s an unloader issue, not a tip issue. Fix the valve, not the symptom.
3. Burner system (hot water units)
If you run a hot-water rig, the burner is the part that breaks the most and gets ignored the most. A burner that won’t light at 9 a.m. on a Monday is a half-day lost.
Three quick checks:
- Fuel filter — install a water-separating fuel filter (RACOR or equivalent) in the burner line if you don’t already have one, and check it daily once you’re in season. Diesel from a gas station pump picks up water sitting in the bottom of a tank — water in the burner line is the single most common cause of a no-light call.
- Burner nozzle — pull it, hold it up to a light, and inspect the orifice. Carbon buildup or a worn orifice changes your spray pattern, and a bad pattern means uneven heat and soot. Replace at the first sign of wear. Nozzles run $8–$15.
- Electrodes — check the gap (usually 1/8″) and the position relative to the nozzle. A misaligned electrode is a no-start that looks like a fuel problem until you’ve spent an hour chasing it.
Burner repairs on the side of the road run $300–$500 plus a lost afternoon. The whole pre-season burner check takes 20 minutes in the shop.
4. Hoses, fittings, and swivels
Walk the length of every pressure hose with the trigger open at low pressure. Pinhole leaks show up as a mist. Soft spots, kinks, and weeping fittings show up by feel.
A pressure hose that fails on a job site is more than the cost of the hose — it’s the cleanup, the explanation to the customer, the lost time. And a hose whipping under 4,000 PSI is a serious injury risk for whoever’s holding the wand.
Check your QC plugs and sockets for sticky seats. Replace any O-ring that won’t seat clean. A $2 O-ring is the difference between a tight connection and a constant drip that wastes water and chemical all day.
If the hose has been on the rig more than two seasons and shows any cover damage, replace it. Reels chew hoses faster than most contractors realize.
5. Trailer — tires, lights, brakes
The most ignored part of the rig is the part underneath it. Tires that looked fine in March may have weather-cracked sidewalls by May. A 525-gallon water tank on top of a soft tire blows out in July traffic and ruins your week.
Pre-season trailer check:
- Tires — check pressure cold against the sidewall rating, inspect sidewalls for cracking, look at tread depth. Tires older than 5 years come off the trailer regardless of how they look.
- Bearings — spin each wheel. Grinding, drag, or play means re-pack or replace before the first long haul of the season.
- Brakes — if you have surge or electric brakes, test them in an empty lot before you put 4,500 lbs of water on the deck.
- Lights and wiring — all four corners, including the brake light. Cops in your service area will pull a contractor trailer for a dead light, and the ticket is the small problem; the delay is the big one.
- Tongue, coupler, safety chains, breakaway — five-minute walk-around. Do it now, not on the side of I-95 in July.
What this is worth on your June calendar
A full pre-season check takes a contractor in a clean shop about two to three hours. Parts to fix what you’ll typically find — pump oil, a seal kit, a unloader rebuild, a burner nozzle, a couple of O-rings, maybe a hose — run somewhere between $80 and $300 depending on what’s worn.
The cost of skipping it: one cancelled job because the burner won’t light, one half-day at a service shop in June, one tow because a trailer tire let go on the way to a commercial account. Any of those wipes out a week of margin.
Do the check this week. Your customers are about to see the difference — when you show up on time, finish faster, and leave their property looking better than they expected. That’s what gets the call back in August, and the recommendation to the neighbor in September.
Get what you need on the trailer by Friday
PowerWash.com stocks every part on this checklist — pump oil and seal kits, unloader rebuild kits, burner nozzles and fuel filters, replacement hoses and QC fittings, trailer tires and bearings. Real contractor-grade parts, not whatever the box store happens to carry that week.
Backed by 50+ years in the trade. Orders ship Ground and typically arrive within 5 business days — order today and you’re ready before the first June booking lands.
