Cooling water restriction
 

Could someone post some pictures and or a diagram of the fitting on the inside of the transom assembly that the cooling water from the drive comes through and corrodes .This causes a problem with water flow .It is a bravo drive.

http://www.mercruiserparts.com/Show_...c=BELL+HOUSING

The bellhousing can corrode and swell where the hose is inserted and squeeze the hose. The problem occurs where the insert is located (part number 4). I fixed mine vs replace by getting in there with a needlegun and getting out all of the corroded aluminum and filling it back in with JB weld. Haven't had any more problems with it. The other option would be to replace the bellhousing.

Rene

I was under the impression that the problem area was inside the boat and i thought in another thread someone said something about some sort of wedges or some thing of the like.Again not sure just trying to gather information

There is a delrin (plastic) neck inside on your transom assy, follow the intake hose to it. It is right under your steering assist,two 1/4" bolts hold it to the t/a, remove it and you should see the restricted/collapsed hose.

Just wamted to bring this thread back up trying to locate pictures of what exactly this looks like both places inside the boat and outside with the drive pulled off

Still trying to gather information, I removed the two bolts on the water neck inside of the transom very hard to work on due to the engine coupler. I removed the water neck and whatever is swelled or collapsed the hole is reduced to about 1/4 inch it would definitely reduce water to the engine. does anyone know what this is and how it comes apart .Pictures would be nice or 1st hand info . I think this problem could be overlooked for anyone with a boat with any age if they were having a oil orwater temp problem.

The part where the water neck (plastic) bolts to is the transom assembly. I had the restriction occur on the drive bellhousing. I repaired mine with JB weld by hitting it with a needle gun to remove the oxidized aluminum and casting a new "hole" with the JB weld. The same could be done on the transom assembly but it would be pretty difficult while it's on the boat.

Rene

Oldandtired thanks for your response I cant tell how the hose or tube is hooked up to the water neck but something is not right I hope someone on here has some more input.

Can you test/diagnose this restriction by putting the flush attachment on the lower unit and pulling the inlet hose off the raw water pump? I know the flush attachment doesn't seal perfectly so you might have to have someone hold it on there?

by removing the water neck I can see the restriction only about 1/4 inch hole under the water neck

Check the hose that goes over the top of the drive unit and then back into the boat for a kink. I cooked an engine a few years ago. The boat was stored for he winter with the drive unit crancked all to one direction. Sitting like this all winter caused a kink inthe water inlet hose. I did not find out until I cooked the engine!

hope that helps

It appears the restriction is directly under the water neck in parts diagrams it looks like a water tube comes through the trsnsom and somehow connects to the part of the transom assembly where the water neck bolts to.the transom assembly and drive are 1989 so they have some age on them, iappreciate the info from whoever. Thanks guys

I seem to recall that the hose goes through the gimble housing (transom) and is secured with the nylon insert. The parts diagram that I was looking at shows only one insert on the bellhousing side. I'll look at my service manual this afternoon.

Rene

I just went through the service manual and there is an insert that secures the hose on the section where the water neck is. There is no "fitting" that the hose attaches to. It simply goes through a hole in the gimbal housing casting and is held in place with the nylon insert which is screwed into the hose thereby expanding the hose and holding it tight. The water neck just bolts to the flat surface where that hose comes through. The reason that there is a constriction is that the aluminum gimbal housing is corroding there and subsequently swells. The swelling is forcing the hose to collapse. Your only options are to repair the gimbal housing or replace it. My repair on the bell housing is about two years old and has not shown any sign of recurrence so I consider my repair method a success. And Yes, I have had the drive off to check it. The swelling aluminum is exactly the same problem in both locations. Unfortunately, it is going to be very difficult, if not impossible, to do the repair with the engine in the boat. Replacement is also near impossible with the engine in the boat. There is always the option of capping the water neck off and going to a through hull pickup.

Good luck,

Rene

Am working on maching it out and inserting a bronze pipe as a bushing. this should keep it from collapsing. Either that taping it and a threaded insert. Corossion will eventually get behind the JB and expand it out. BBB

try this one for more info:

http://www.offshoreonly.com/forums/s...d.php?t=122072

see attachment where #14 is the water hose.

Old and tired you are right on , i found out that the fitting i was talking about is the plastic screw in insert. It was hard to tell what or how it went together because it was so distorted from the corrosion .I went to a shop and they showed me the new parts and how it goes together. I have been chasing this problem for 3 years ,it was never enough to put me completely out of service but i knew something was not right .Members with temp. problems that have checked everything else should check here especially if your boat has any age on it. I am deciding to either try to repair which is veryhard to get to or go to a transom mounted water pick up . What are some of the members thoughts on this.

Codered,
HOw were you able to replace this without puling your engine?

Were you able to get to it by removing the drive unit on the outside of the boat?

Is your drive a Bravo 1?

I didnt replace anything yet all i did was pull the water neck off and i could see the restriction , Yes it is a bravo . The mechanic i talked to gave me the long and the short way of repairing and i am still looking into putting a transom mounted pickup on it you should be able to see the water neck without pulling the engine or the drive . Pm me your phone # and i can call you about it Dirt head

I had the same problem X 2. On one of them (stb) I was able to remove the hose, clean out the corrosion with a dremil tool, paint with green oxide, silicone and a new hose n' insert with the engine in the boat.
The other engine, well, it had to be pulled to rebuild because the problem went too long. Good luck

641-919-3406

Thanks

Adrian