Generac Pressure washer, several problems after service.
#1
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Thread Starter
Generac Pressure washer, several problems after service.
I brought my Generac pressure washer in for service simply because the threads on the fitting that connected to the pressure hose were galled for unknown reasons (I am always super careful).
The pressure washer has just about 2 weeks left on the warranty. It has been pretty good to me until I turned it in for service.
I asked Generac to simply send me the fitting but they refused since the item was on the pressure washer itself. They did send me a new pressure hose with no issues.
Below is the pressure washer in question.
http://www.amazon.com/dp/B004T6UFDS/..._M3T1_ST1_dp_1
When I got the pressure washer back from service I started it up. It began to emit blue smoke badly.
I shut it down and checked the oil.
The oil poured profusely out from both dipsticks.
I changed the oil and the level now remains the same, however the idle races up and down very rapidly now. The rods to the carb (move back and forth very quickly now).
The pressure washer is very smooth when I pull the trigger to use it (yes I always run it with water), but the second I let go of the trigger the idle is very fast and unstable.
I am scared to bring it back to these guys. They advise that sometimes things just happen.

I am concerned that someone overfilled the oil or that gas is running into the oil supply and mixing.
I'd figure that Generac doesn't cover seals if that just happens to be part of the problem or the problem. They could have just avoided all of this by sending me the fitting.
Thoughts?
Thanks
The pressure washer has just about 2 weeks left on the warranty. It has been pretty good to me until I turned it in for service.
I asked Generac to simply send me the fitting but they refused since the item was on the pressure washer itself. They did send me a new pressure hose with no issues.
Below is the pressure washer in question.
http://www.amazon.com/dp/B004T6UFDS/..._M3T1_ST1_dp_1
When I got the pressure washer back from service I started it up. It began to emit blue smoke badly.
I shut it down and checked the oil.
The oil poured profusely out from both dipsticks.
I changed the oil and the level now remains the same, however the idle races up and down very rapidly now. The rods to the carb (move back and forth very quickly now).
The pressure washer is very smooth when I pull the trigger to use it (yes I always run it with water), but the second I let go of the trigger the idle is very fast and unstable.
I am scared to bring it back to these guys. They advise that sometimes things just happen.

I am concerned that someone overfilled the oil or that gas is running into the oil supply and mixing.
I'd figure that Generac doesn't cover seals if that just happens to be part of the problem or the problem. They could have just avoided all of this by sending me the fitting.
Thoughts?
Thanks
#3
Member
With that much overfill, if gas was causing it, you would have a heavy gas smell to the oil. The question is why the oil level is stable now and you're still experiencing the hunting and increased idle speed. Both can be caused by lean idle mixture. In an overflow of the gas from the carb, however, you would be getting a flooded condition.
Their explanation for the problem as well as them not running the washer before sending it back seems a little odd.
Their explanation for the problem as well as them not running the washer before sending it back seems a little odd.
#5
Was the oil thin and gassy smeling? It sounds like there was crud in the carburetor at the bottom, then with the shaking around during transport, the crud got stirred up and got in the needle and seat area, causing the leaking oil into the crankcakse and also it got picked up by the main jet and is causing a restriction (the surging is caused by a fuel restriction).
#6
Member
Thread Starter
All,
I didn't really observe whether or not the oil was thin. My nose is not as good as it used to be, but I think it smelled more like oil.
I am leaning towards it being a temporary slosh around situation that did "permanent" damage...although the oil no longer seems to be overflowing out of the crankcase and it *looks* like regular oil.
As far as any non intrusive remedy for the carb, is there?
Also, what about the idle screw? Anyone know where that is?
Thanks
I didn't really observe whether or not the oil was thin. My nose is not as good as it used to be, but I think it smelled more like oil.
I am leaning towards it being a temporary slosh around situation that did "permanent" damage...although the oil no longer seems to be overflowing out of the crankcase and it *looks* like regular oil.
As far as any non intrusive remedy for the carb, is there?
Also, what about the idle screw? Anyone know where that is?
Thanks
#7
Non intrusive? The only thing that I might suggest is adding seafoam to thegas and run it a while, then let it sit and try it again every few days to see if it dissolved the trash restricting the jet. I would just open the carb and clean it.
#8
I think that's a G19 Honda engine on that unit.
From what I see and is stated in the info is that it is a Generac engine. Now just who make it is another question but also, in the customer reviews, it is mentioned several times that it is NOT a Honda engine.
Having a model No. off the engine might provide some more info. I honestly doubt that it has any carb adjustment.
Normally surging is a sign of a lean mixture most times caused by restriction or vacuum leak. However, in my experience, the symptoms you describe are not untypical of most pressure washers I have worked on or dealt with. I have a theory of why this is but it just that.
As long as it maintains full pressure with the wand triggered, and it stays running without, I would just use it and keep an eye on the oil situation.
#9
Where is the engine made?–
The engines used on the Generac XP and XG Series of portables are manufactured at our Generac Power Systems, Inc. factory in Whitewater, WI. Generac engines are industrial grade engines designed to provide the ultra-quiet, longer-lasting performance required of portable generators. They also run 30-50 degrees cooler, are 5% more fuel-efficient and reduce oil consumption by 25%.
The engines used on the Generac XP and XG Series of portables are manufactured at our Generac Power Systems, Inc. factory in Whitewater, WI. Generac engines are industrial grade engines designed to provide the ultra-quiet, longer-lasting performance required of portable generators. They also run 30-50 degrees cooler, are 5% more fuel-efficient and reduce oil consumption by 25%.
#10
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Oops it was a G160 I was thinking about. My buddy sold the washer and all he remembers it started with a G. Thanks for the correction.
There should be a idle screw on your carb. You might not have an adjustable jet for low speed. The idle screw will be next to the butterfly plate on top if you have one.
There should be a idle screw on your carb. You might not have an adjustable jet for low speed. The idle screw will be next to the butterfly plate on top if you have one.
#11
I doubt that there is an idle screw, since these machines are never meant to idle, Thus, plays into part of my theory of why most of these surge under NO LOAD! but otherwise operate normal.
My Theory:
Since pressure washers need to produce high torque, and be readily available to do so, I would assume the carburetors to have bigger jets. Most that I have seen have no throttle control and there fore run at full throttle. When there is not load, the governor senses the over speed due to more fuel being injected by the full open of the throttle valve. It then senses an overspeed and cuts the opening of the throttle valve to compensate. The rapid response of the governor is what causes the surging IMO and not a restriction of fuel or over induction of air.
This is also indicative of most internal combustion engines that drive hydraulic pumps (yes water is hydraulic) A pressure washer should not be left to run under NO LOAD, any longer than necessary.
Most of the best hydraulic powered equipment use Horizontal shaft engines. The main reason is because they produce more torque with a lower HP rating. Mainly due to the orientation of the engine it is able to provide a longer stroke (like a tractor engine) within the same space. A vertical shaft engine needs more RPM to produce the same torque and is more susceptible to changes in load.

Az
My Theory:
Since pressure washers need to produce high torque, and be readily available to do so, I would assume the carburetors to have bigger jets. Most that I have seen have no throttle control and there fore run at full throttle. When there is not load, the governor senses the over speed due to more fuel being injected by the full open of the throttle valve. It then senses an overspeed and cuts the opening of the throttle valve to compensate. The rapid response of the governor is what causes the surging IMO and not a restriction of fuel or over induction of air.
This is also indicative of most internal combustion engines that drive hydraulic pumps (yes water is hydraulic) A pressure washer should not be left to run under NO LOAD, any longer than necessary.
Most of the best hydraulic powered equipment use Horizontal shaft engines. The main reason is because they produce more torque with a lower HP rating. Mainly due to the orientation of the engine it is able to provide a longer stroke (like a tractor engine) within the same space. A vertical shaft engine needs more RPM to produce the same torque and is more susceptible to changes in load.

Az
Last edited by BFHFixit; 11-28-15 at 03:18 PM.
#12
Member
Thread Starter
Thanks everyone, I might just leave it alone. I appreciate the additional information as well!!
Cleaning the carb. Any good links on that? I have grown up with fuel injection!
Non intrusive....seafoam sounds good to me!
Cleaning the carb. Any good links on that? I have grown up with fuel injection!
Non intrusive....seafoam sounds good to me!
#14
Member
Thread Starter
Now the thing isn't putting out any more than the pressure it gets from the garden hose.
Any idea what that can be? I figured I'd just post back to the same thread.
Thanks
Any idea what that can be? I figured I'd just post back to the same thread.
Thanks
#18
Member
Thread Starter
Thanks for the thoughts. I am mechanically inclined enough, it's just a matter of being able to find time.

#19
Member
Thread Starter
Back from the grave. Might as well use this thread since all the info is here already. The no building pressure was the result of a kinked hose. It went on to run fine for another few months. I turned it on today without water. I was tired and forgot to turn on the hose valve. I realized this after about a minute as I witnessed water shooting out of the wand fitting. I forgot to connect the wand as well.
After shutting it down, connecting the wand hose, and opening the hose valve I noticed that it was not building pressure.
Over the past few months I have had this problem come and go as the result of a kinked hose.
I removed the diverter valve, cleaned it up, lubricated it with quality grease and put it back together.
The issue persists.
Have I burnt up my pump? I don't think it makes sense to buy a new diverter valve that I can't return just to try it. I should have just taken a nap instead.
Any ideas?
Thanks
After shutting it down, connecting the wand hose, and opening the hose valve I noticed that it was not building pressure.
Over the past few months I have had this problem come and go as the result of a kinked hose.
I removed the diverter valve, cleaned it up, lubricated it with quality grease and put it back together.
The issue persists.
Have I burnt up my pump? I don't think it makes sense to buy a new diverter valve that I can't return just to try it. I should have just taken a nap instead.

Any ideas?
Thanks
#21
About all you can do is dissect until you find the problem. Maybe a couple of check valves are stuck open or ???.
#22
Member
Thread Starter
Would check valves be in this assembly?
3000 PSI PRESSURE WASHER PUMP FOR GENERAC 6024 60240 6412 6436 | eBay
Sorry I don't know much about small engines.
I mean, If the unit runs but doesn't build pressure would replacing that part which includes the pump be sufficient or are there other parts that could cause that problem?
I mean it's half the price of a new unit (on sale) which is ALOT IMO, but if that would rule everything out I'd consider it.
Thanks!
3000 PSI PRESSURE WASHER PUMP FOR GENERAC 6024 60240 6412 6436 | eBay
Sorry I don't know much about small engines.
I mean, If the unit runs but doesn't build pressure would replacing that part which includes the pump be sufficient or are there other parts that could cause that problem?
I mean it's half the price of a new unit (on sale) which is ALOT IMO, but if that would rule everything out I'd consider it.
Thanks!
#23
Yes, the check valves and all parts related to the making of pressure would be in that assembly. Replacing the entire pump assembly would fix your pressure problem. As long as the engine runs good and this pump fits, it is a viable option.
#24
Member
Thread Starter
Thank you.
One weird thing this pressure washer does is not want to shut off when I hit the off switch. It stutters and keeps running for about a minute. I have to shut the fuel supply lever to get it to cut off completely. Kind of like an automotive engine "dieseling"
Ever hear of that? That is the only thing that would make me think twice about making the plunge on that assembly.
One weird thing this pressure washer does is not want to shut off when I hit the off switch. It stutters and keeps running for about a minute. I have to shut the fuel supply lever to get it to cut off completely. Kind of like an automotive engine "dieseling"
Ever hear of that? That is the only thing that would make me think twice about making the plunge on that assembly.
#25
I think you need to take the pump apart, I think you will find the original valves were made of plastic and have gotten overheated and are distorted, a kit to replace them is about $20. Been there done that. Have a good one. Geo
#26
The shut down problem could be a bad switch or bad connection to the coil from the switch, both easy cheap fixes.