1976 120hp pressure release.

[roverfj1200]

Hi all

Have a 120 hp chrysler 1976 and it has a seized (plug) cover on the water pressure release valve.

What is the best way to remove it as the valve seems to be stuck open causing over heating at low rev's.

Cheers

Richard

 

[jerryjerry05]

Re: 1976 120hp pressure release.

Find justintide's latest thread.It shows a good cause of overheating.
What have you done to rectify the problem already?The impeller new.?Change/check the thermostat?
One way.The cover is hard to get at.Loosen the lower cowl and use a dent puller.Or get in there with a small pry bar.PB Blaster.Then start tapping it gently with a hammer.More PB,more tap-tap-tap.Let set with PB,start again.Then possibly a hot wrench(torch).J

 

[roverfj1200]

Re: 1976 120hp pressure release.

At idle no water makes it to the thermostat. And the release valve would seem to me to be the cause in that case.

Will practice on a old 135 power head I have first..

Cheers
Richard

 

[jerryjerry05]

Re: 1976 120hp pressure release.

How old is the pump?How about the impeller?
Does it do in in the water too?You sure there is enough water on the hose?
The muffs on right? Duct tape them in place.Tape them when the unit is dry.
More info would be helpfull.Tell us the whole story.J

 

[roverfj1200]

Re: 1976 120hp pressure release.

I have a tattle tail fitted to the thermo housing. I have to rev the motor high on the muffs to get water to run from it.

When motoring out of the harbour at idle steam comes out the tattle tail until I lift the revs some what.

With the lower unit removed and a hose placed on the water intake water runs freely from the exhaust housing before the tattle tail runs.

Cheers Richard..

 

[jerryjerry05]

Re: 1976 120hp pressure release.

What shape is the impeller?The pump housing.Post a few pics.
At idle you should push a lot of water.
If the valve is stuck open or closed.You should still pump enough water to cool the engine at idle.
How much water is comming out the holes on the back of the motor?J

 

[roverfj1200]

Re: 1976 120hp pressure release.

The impeller and housing are new and yes a good amount of water sprays from the exhaust out lets..

will post a pix of set up later..

Thanks