502 Mag h20 pressure.
 

Gauge reads no pressure but water still coming out of pipes good . Line is not clogged , with fitting out of block , still no water comes out .

Re: 502 Mag h20 pressure.
 

where is this hooked up to on the block? At the bottom block drain? Stick a screwdriver in there and see if you have mud or sand blockage....

Re: 502 Mag h20 pressure.
 

It's threaded into a hole in the left side of the block about halfway to the front , I can't get the engine hotter than about 130 , but the hotspots this could create bothers me .

Re: 502 Mag h20 pressure.
 

Is it possible that someone switched the hole for the knock sensor with the water pressure hole ? Is there water in the hole for the knock sensor ?

Re: 502 Mag h20 pressure.
 

Sounds like sediment inside the block...as Wally said, stick something inside that block drain and get the "gunk" out of it. If your block is full of gunk, typically you would run hotter. perhaps pull both side block drains and make sure they are both clear. I usually only worry about this at winterizing time unless something else goes wrong (burn impeller).

Re: 502 Mag h20 pressure.
 

Are you running this on a hose or in the water????

My h20 pressure guage doesn't move on the hose.

If this is happening in the water, then pull the fitting that goes into the block. Water should come out in steady stream. If it doesn't, it's plugged up. Shove a small screwdriver in the hole to unclog it.

I have to unclog mine a couple times a year.

Re: 502 Mag h20 pressure.
 

no, knock sensor doesnt have water, maybe your right. check it out, that would be an easy fix!!!

Re: 502 Mag h20 pressure.
 

Fixed it last night ..... Pulled the knock sensor and about a gallon came out , swithched the knock and the pressure fitting , now all is well . Reads about 1 psi at idle and about 10 psi at 1200, other side does about the same . thanks.

Re: 502 Mag h20 pressure.
 

guys the best place to run the water press line that Will not get plugged up is the 1/8 npt hole in the pump I now it's intended for draining and priming and all the other things they come up with but we've been plumbing our press there since the 80's and it doesn't cause any problems never gets plugged up and when you want to drain for storage remove the fitting and do so every other place will stop up the hose the fitting or worse damage the gage.