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Raw water flow issue

D

doubleg

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i'm looking for possible a

i'm looking for possible answers as to why the port side water flow coming out of the exhaust is noticeably less than the flow coming out of the starboard side exhaust. This is causing the engine to run at about 195 degrees too hot for my liking. I have traced the water flow from the intake into the v drive up into the water pump then into the heat exchanger coming out of the heat exchanger it splits with a t going to both elbows. I have replaced the impeller. Since I have a good flow coming out of the starboard side exhaust I thought that the only other possibility for the reduced flow on the port side was from a bad elbow. I replaced the port elbow the flow increased however it is still noticeabley less than the starboard side and the engine temp is still hovering close to 195. I cant seem to fiqure it out. Any ideas would be greatly appreciated. Oh yeah this is a 350 cid.
 
"Gary,

Pull the hoses off o

"Gary,

Pull the hoses off of the elbows and start the engine. See if you have comparable flow from both hoses. If you do not, based on the description of your system, the problem can only be the tee or the hose feeding the riser from the tee. It is possible there is a blockage or the hose has delaminated internally. If you don't have one, go buy a Lasar pyrometer. Compare the temp at the temp sender to the reading on the gage, you may not have a temp issue at all, it could be a gauge issue.

Also, take engine surface temps at different points on the engine, compare temps between both elbows. This will verify if this water flow issue is actually causing your increased operating temp.

Goods luck
Rick"
 
"Rick, Thank you for your repl

"Rick, Thank you for your reply I didnt think of pulling off the hoses at the elbows. Unfortunately I found this web site too late and am out of the water now. The gauge being wrong is also a good possibility its 30 years old. One other thing I thought of might be a possible obstruction in the muffler. I am hoping that a faulty gauge and a muffler obstruction might be the problem. Once I am in the water I will check the hoses and try the laser pyrometer as you suggested. Thank you once again for the help.

Gary"
 
"in an attempet to correct thi

"in an attempet to correct this water flow issue, i deciced to replace the entire cooling system. upon removing the sherwood circulator pump on the port engine the water intake was on the right side of the pump with the outflow going to the oil cooler on the left side. when i removed the starboard engine's sherwood circulator pump the water intake was on the left side of the pump and the outflow going to the oil cooler was on the right side. knowing that both engines are left hand rotation, i immediately thought the waterflow issue on the port motor was caused by having the intake hose on the wrong side of the circulator pump. to verify this i took the covers off of both circulator pumps expecting to find the same rotation on the impellor. much to my disbelief the rotations on the impellors were opposite of each other. my question now is how is this possible when both engines are left hand rotations. the engines are out of the boat so i can not turn them over to double check the rotation however on both intake manifolds the firing order reads 18436572 which is the correct firing order for a left hand rotation engine. the sherwood stamped circulator pumps have no numbers on them distinquishing any difference they appear to be sherwood 35 circulating pumps. how is it possible that left hand rotation engines that turn the circulating pump in the same direction have different intake and outflow on said circulating pumps. i think i am going crazy any help would be greatly appreciated."
 
sounds crazy but I had the sam

sounds crazy but I had the same issue. I had growth just inside the thru hull by the seacock. had to remove the seacock and clean out. all is well.
 
"In the rear of risers are a s

"In the rear of risers are a series of small holes the water shoots out of to join the exhaust. These holes are easy to plug up--that's why silicone should not be used on manifold gaskets. I suggest you remove the riser on the side that's running hot and stick a hose in it (where the water enters). If you don't see water shooting out those little holes, then you'll have to rod them out.

Jeff"
 
"just for thought.....On my la

"just for thought.....On my last summer trip of all times I saw my temperature climbing up and shut the boat down to check.As Rick said,with a laser pyrometer I determined an impeller going down.Took the time to replace it while anchored off shore at a bad location called Turkey Point in the heat.Jeff...you know this place well I am sure.Upon leaving temp stayed at 195.After 10 minutes I shut down again,anchored, took pump apart again to find that when putting new impeller in, the woodriff key pushed out of the slot allowng water to travel when running, but not near enough as pump was not working properly.Perhaps this happened to you also.I now carry a new pump as a spare....easier to replace on the water and can rebuild at next destination."
 
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