4hp johnson running hot

[sambrigman]

I have replaced with complete water pump replacement, Still running hot. Removed cylinder head, water coming from all holes on bottom cyl. none from top cylinder. Any ideas? thanks guys

 

[racerone]

model # is ?

 

[Calebwitdafro]

When you say you removed the cylinder head, do you mean the cylinder cover plate, or the plate and cylinder head? Did you have water coming out the tell tale?

 

[Crosbyman]

when you installed a new impeller did it have all it's vanes or some broken ??

some bits may have been circulated up the engine

try blowing out the water passage holes at the rear of the water jacket


one supplies water the other is likely an exit so don't expect water from both ..

 

[sambrigman]

The old impeller looked fine, i had the new one so i replaced it.i blow thru all the holes and only 1 hole blows air out the exaust holes. Is it possible that only 1 hole is intake?

 

[Crosbyman]

see picture...... water comes from the top drains at the bottom


i would think that air should pass freely in or out of the water jacket flow route

try fishing a weed wacker string in both water supply and exit routes of the jacket ... keep probing


Colonoscopy.... if nothing works you could try lifting the power head of it's base and work from the bottom up

 

[oldboat1]

With the lower end removed, push hose water up the tube (engine off) to flush. Note exit as you have been doing. Flush downward as well if the heads are off. Water should exit into the leg. The end of a hose quick release can work to reduce the circumference of the hose outlet.

 

[racerone]

The exhaust cover is not fully water cooled and can get quite hot.

 

[Crosbyman]

you should the archives here nad utube lots of info

 

[sambrigman]

the top cylinder is getting to hot to touch, all the exhaust holes are showing exhaust, almost no water

 

[racerone]

Water pump impeller MUST be fully submerged in water to work.---Water must be 8" above the impeller.

 

[Crosbyman]

back to basics..... if you force air or water up the water tube (with the l.u. removed ) does the air/water seem obstructed if not clean the water pathway remove the PH of the base it need be !

if all seems ok ..... then the water pump or inlet to the pump is not working properly

did you inspect the water inlet to the pump

when you worked on the pump housing did you clean out the small purge hole in the top casing it is hard to see but clean it out

 

[Crosbyman]

see text

 

[Crosbyman]

see pics