Trojan Boat Forum

Hello again everyone. Started my 1974 f25 with 318 and seems to be running well. water coming out both manifolds . No smoke . Port side manifold is cool , starboard side is running hot and or warm after few minutes of idle . Rest of engine seems to be normal temp . Has anyone come across this and any ideas what could be ? It even stumped my mechanic ,both manifolds were taken out , cleaned out last year before winter and put back on with new gaskets.

I just experience this on my f26. First I read temp with a laser temp guage.
Mine was running about 200 deg. I took off exhaust riser and the other end cap.
I took and old oil dipstick and dug around. It should pass all the way through fwd to aft.
Put end cap back on and run a garden hose to it flush it out of riser side.

WARNING....MAKE SURE YOU PUT A TOWEL IN THE EXHAUST PORT PRIOR TO FLUSH. THAT WILL ENSURE
YOU DO NOT GET ANY WATER INTO THE ENGINE EXHAUST.

I caught the debris on a towel. I was surprised how much came out,

Manifold temp about 90 deg at idle...

There is a copper or brass tube that runs the entire length of the manifold which is inserted and removable. Each one has six quarter inch holes in them which diverts water into the manifold interior and out the exit end, the remainder of the water flow goes on into the riser and out to cool the various hoses and joints. The point is that the holes are small enough to clog with junk. When I installed my engines I put new tubes in. Some say the tubes not needed. I opted for them and manifolds are warm but touchable. I would bet the manifolds would be much cooler without them as water could flow straight through manifold voids at full force. I am a firm believer that usually the original engineers had it right so I kept it original.

Bob a Beacon says he they never use the tubes and he used to work for Trojan.

So a mystery, but tubes or lack of tubes could be causing your issue.