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epatti1062
11-01-2009, 01:28 PM
To it out today for trial run WOW. I a few problems exhaust rise getting hotter than the other pulled the hose off the theromastat housing ran water hose to it flows great. Please help Tim

cutwater
11-01-2009, 01:40 PM
To it out today for trial run WOW. I a few problems exhaust rise getting hotter than the other pulled the hose off the theromastat housing ran water hose to it flows great. Please help Tim

How much hotter? Some temperature variation is normal, my boat does the same thing. Both should be somewhat warm, but not burning hot. I.E., you should be able to leave your hand on the riser for at least a few seconds without burning yourself.

What exhaust do you have? Stock Mercruiser? How old are they, and do you see any rust on them? The water passages could be restricted by rust and iron scale if they are old.

epatti1062
11-01-2009, 03:00 PM
How much hotter? Some temperature variation is normal, my boat does the same thing. Both should be somewhat warm, but not burning hot. I.E., you should be able to leave your hand on the riser for at least a few seconds without burning yourself.

What exhaust do you have? Stock Mercruiser? How old are they, and do you see any rust on them? The water passages could be restricted by rust and iron scale if they are old.

new motor etc. aluminum manifolds and riser. i can leave my hand on one all day and the other for a few seconds
thanks tim

mrfixxall
11-01-2009, 04:15 PM
Put a hose clamp on the hose and tighten to restrict the flow of water and see if the hot one cools down..

MOP
11-01-2009, 06:20 PM
Is it the thermostat housing with the nylon balls on the rod with the springs, If it is the balls wear and stick, if they have not already been turned on the rod so the good round side it toward the housing do it. If both sides of the balls are worn you are better off swapping to a late style with out the ball, if that is the case PM me I have one.

Phil

MOP
11-01-2009, 06:22 PM
Put a hose clamp on the hose and tighten to restrict the flow of water and see if the hot one cools down..

Mike if it has the ball style it will fool you clamping one hose down, yes it will flow more until the ball sticks again!

FISHIN SUCKS
11-01-2009, 07:09 PM
If all other tests mentioned above check out okay, do you recall disintegrating a water pump impeller? I had that happen the end of last year and thought I had removed all the rubber blades......turns out I still had one rubber blade blocking water to one of my manifolds (starboard side) up in the thermostat housing. Good luck in your endeavor,
tom

epatti1062
11-01-2009, 07:13 PM
If all other tests mentioned above check out okay, do you recall disintegrating a water pump impeller? I had that happen the end of last year and thought I had removed all the rubber blades......turns out I still had one rubber blade blocking water to one of my manifolds (starboard side) up in the thermostat housing. Good luck in your endeavor,
tom
new inpeller, engine, manifolds, risers, water pump, thermostat housing is used it had some rot bead blasted water ran through with no problem. thanks tim

miike
11-01-2009, 08:58 PM
you can always have the manifold pulled and checked. just a couple hours labor and gaskets.

MOP
11-02-2009, 07:13 PM
As you said in in the initial post on a hose the manifold flowed well, so the problem should be before the manifold.

epatti1062
11-05-2009, 06:54 PM
To it out today for trial run WOW. I a few problems exhaust rise getting hotter than the other pulled the hose off the theromastat housing ran water hose to it flows great. Please help Tim

Today i check water flow out of the thermostat manifold and was the same on both sides. Temp at the top of the riser @ idle i had 110 and 122. @ 2000rpms i had 115 and 140
Please advise Tim

MOP
11-05-2009, 07:04 PM
You rarely see any setup where the manifolds are match in temp, my stbd. riser is always hotter than the port.

Question do you or do you not have the thermostat housing with the nylon balls on a brass rod in the outlets to the risers????

epatti1062
11-05-2009, 07:57 PM
You rarely see any setup where the manifolds are match in temp, my stbd. riser is always hotter than the port.

Question do you or do you not have the thermostat housing with the nylon balls on a brass rod in the outlets to the risers????
No i have the newer style no balls. My next questions is how hot is too hot? I have a 160 thermostat. Thanks Tim

MOP
11-05-2009, 08:28 PM
I would drain the manifold and take that riser off, if it appears clean and not showing of much corrosion buy a gasket and put it back on. I the riser looks cruddy inside and before you knock any junk loose, post at least one straight on shot to judge deterioration is good, make sure it is clear.

Phil

mrfixxall
11-05-2009, 08:37 PM
No i have the newer style no balls. My next questions is how hot is too hot? I have a 160 thermostat. Thanks Tim


you should have a 140 t-stat in it..

epatti1062
11-05-2009, 09:28 PM
I would drain the manifold and take that riser off, if it appears clean and not showing of much corrosion buy a gasket and put it back on. I the riser looks cruddy inside and before you knock any junk loose, post at least one straight on shot to judge deterioration is good, make sure it is clear.

Phil
New aluminum maniforlds and risers installed with new motor.
Thanks, Tim

robertbj
11-05-2009, 10:00 PM
If your engine is set-up like mine, the port manifold gets direct cold lake water from the sea pump. The starboard manifold gets cold water if the thermostat is closed, but when it opens, all the hot water from the engine go’s out the port side making that manifold quite warm.
Bob

epatti1062
11-05-2009, 10:26 PM
If your engine is set-up like mine, the port manifold gets direct cold lake water from the sea pump. The starboard manifold gets cold water if the thermostat is closed, but when it opens, all the hot water from the engine go’s out the port side making that manifold quite warm.
Bob

Good info thanks
this is the housing i am using and fresh water supplied from alpha 1 gen 1 impeller

MOP
11-06-2009, 06:19 AM
If your engine is set-up like mine, the port manifold gets direct cold lake water from the sea pump. The starboard manifold gets cold water if the thermostat is closed, but when it opens, all the hot water from the engine go’s out the port side making that manifold quite warm.
Bob

Retrace your hoses the way you describe your set up the hoses are routed wrong, both feeds for the risers/manifolds are fed from the thermostat housing. They are fed from a common chamber, in a raw cooled system they are initially fed by a by pass hole in the housing until the Tstat opens.

I would like to see a heat gun reading at higher speeds, what is the actual temp they do on every setup get pretty hot. Maybe you are just spooked and the temps are within the norm range. I have aluminum headers they feel quite hot especially the stbd side, believe me I have more then enough water flow.

epatti1062
11-06-2009, 06:51 AM
Retrace your hoses the way you describe your set up the hoses are routed wrong, both feeds for the risers/manifolds are fed from the thermostat housing. They are fed from a common chamber, in a raw cooled system they are initially fed by a by pass hole in the housing until the Tstat opens.

I would like to see a heat gun reading at higher speeds, what is the actual temp they do on every setup get pretty hot. Maybe you are just spooked and the temps are within the norm range. I have aluminum headers they feel quite hot especially the stbd side, believe me I have more then enough water flow.
today i will do a run test and get speed temps. thanks tim

TBroccoli
11-06-2009, 11:11 AM
My risers are different temps. Mercruiser stated that is normal. My stbd side is the hotter of the two. I initially pulled everything apart. It all looked clear so I put it back together. The boat ran great all season. I have a 160 degree t stat. Engine temp runs between 165 and 175.

epatti1062
11-07-2009, 08:22 PM
My risers are different temps. Mercruiser stated that is normal. My stbd side is the hotter of the two. I initially pulled everything apart. It all looked clear so I put it back together. The boat ran great all season. I have a 160 degree t stat. Engine temp runs between 165 and 175.
Took the minx out friday temps were 143 on the port side and 165 starboard. got about 45 min. of riding then water in the fuel. Time to drain the tank Thanks Tim

MOP
11-07-2009, 09:23 PM
Manifolds are fine, they will always be hotter then the engine.

IMO take the fuel gauge sender out and suck out the water from the bottom of the tank.