Pressure washer head stuck on GX390 crank

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rkcarguy
Posts: 1505
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Pressure washer head stuck on GX390 crank

Post by rkcarguy » Sat Feb 15, 2020 4:24 pm

I acquired a GX390 pressure washer that has some issues and the engine is locked up. It has a CAT 66DX pressure washer pump on it that seems to be in good shape but it's also stuck on the crankshaft and I don't want to ruin anything. The bolts that secure the pump to it's bell-housing are of course inside the housing so no access. :roll:

The only thing I can think of is to drill a hole in the bell-housing and then apply some heat with a propane torch to see if I can wiggle things loose, or remove that 4 bolt cover plate and maybe bolt on a plate there with a threaded rod welded into it and try to slide hammer it off of there?

Attached the exploded view of the pump so you can see what I'm dealing with.
Catpump.jpg

John Hasler
Posts: 1600
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Pressure washer head stuck on GX390 crank

Post by John Hasler » Sat Feb 15, 2020 5:21 pm

Are you trying to salvage both the pump and the engine, or just the pump?

rkcarguy
Posts: 1505
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: Pressure washer head stuck on GX390 crank

Post by rkcarguy » Sat Feb 15, 2020 5:44 pm

I'm trying to salvage both if possible. Oil doesn't smell or look bad so I'm thinking the engine may be stuck at the rings from sitting for years.
I just sprayed a bunch of PB blaster into the spark plug hole and I'm going to let it soak until tomorrow and see if I can't crack it loose.
The last one I worked on had a dead pump but good engine, so I sawed through the bell housing with a Port-a-band and then used the torch to heat up the coupler until it slid off the crank.

John Hasler
Posts: 1600
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Pressure washer head stuck on GX390 crank

Post by John Hasler » Sat Feb 15, 2020 9:37 pm

If both valves are closed try compressed air. It will both apply force to the piston and drive whatever lubricant you put in the cylinder down into the rust.

rkcarguy
Posts: 1505
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: Pressure washer head stuck on GX390 crank

Post by rkcarguy » Sat Feb 15, 2020 11:10 pm

The PB blaster broke it loose, it wasn't stuck all that bad. The starter rope was also frayed and was catching inside the starter recoil and then broke, so I rewound it with some west marine sailing cord (1,200# rated and nice and soft, about same size)....and it runs! I didn't run it long because I don't want to damage the pump just a few seconds.
I just need to get it to separate from that pressure washer pump, I'd like to use the engine to repower my Struck mini dozer.

John Hasler
Posts: 1600
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Pressure washer head stuck on GX390 crank

Post by John Hasler » Sun Feb 16, 2020 8:54 am

Do you have a use for the pump?

rkcarguy
Posts: 1505
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: Pressure washer head stuck on GX390 crank

Post by rkcarguy » Sun Feb 16, 2020 4:47 pm

I do not, thought if I could save it though that it could be "offerup'd" as I looked up the pump number online and Northern Tool sells it for $599 new.

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