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Water impeller play

was it pumping normally before

was it pumping normally before?

are there any visible cracks in the wp housing?

i hope its not busted inside and you have to replace the whole inner ex tube.
 
"It was pumping before. I see

"It was pumping before. I see no cracks in the housing. how hard is it to pull the exhaust housing? here is something I just found out that may be a clue to you experts. I have the gearcase removed. when I blow in the pee tube and seal the hole at the bottom of the exhaust housing where the water pump grommet goes, I still hear air escaping somehwere. is this supposed to be a sealed passagway to the pee hole. I wouldn't think so, because the water has to get to the engine. just a thought that maybe would give a clue."
 
well if it was pumping before

well if it was pumping before it blows a hole in that theory.

i think it should be sealed unless you have a stuck thermostat.
 
"does this look like what you

"does this look like what you have,the tube with the arrow fits into the engine when its all bolted up, if you missed it there will be no water
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hey is that for sale?!.......l

hey is that for sale?!.......looks just like mine......i wish!----i would really like to have it though.

isnt that arrow on the driveshaft?!......and the wp pick up tube goes in just below the arrow?!

have you looked up his motor diagram?.......i looked it up on shopevinrude.com and couldnt find a pick up tube.
his inner exhaust housing is a lot larger than the older models........looks like maybe the water pick up is integrated on his.
 
I don't have that tube tha

I don't have that tube that is just below the arrow in the pic. mine has a rubber connector that is made with a cone shape on top. this pushes into the exhaust housing hole.
 
"I think the question that nee

"I think the question that needs to be addressed is this. with the gearcase off, I can blow in the pee tube and hear air coming out the bottom of the exhaust housing at the hole that the water pump outlet grommet goes in. but when I block this hole with my finger and blow in the pee hole, I still hear air somewhere. it sounds like I hear it coming out the exhaust tube at the bottom of the exhaust housing. is this normal? I guess one of you experts that know the water system in this engine will have to answer this."
 
"If I understand this discussi

"If I understand this discussion correctly, Dan's question partly has to do with the flow of water in the cooling system.
The water system has one inlet; the water pump supplying water pressure to cool the engine. But, the water outlet occurs in multiple places. One outlet is the pee hole. Also, water from the block outlets in the junction of the exhaust adapter plate. This water eventually exits thru the prop.
So, simply blocking the pee hole, and pressurizing the water inlet at the bottom of the exhaust housing will NOT give you a sealed system to test for leaks with.
Air will flow all thru the block, exhaust adapter, and on out into the void between the inner and outer exhaust adapters, basically it will blow everywhere.
That exhaust adapter is a myriad of passages and bypass holes, etc.

Dan, is that the answer to your question? Other than you get no water flow when the L/U is installed?

I had the same issue on a 96' 200. I tore it down and found that I missed aligning the outlet of the water pump with the water pick up tube.
Re-installed, just like David Real says, with a long screwdriver to poke and push the tube into position...and then I was good to go.

It sounds like you do not have a good connection from the water pump outlet to the mating piece in your exhaust housing. (Since you seem to not have a water tube.)
I would concentrate on that, and put aside other unlikely ideas, like a bad inner exhaust housing, etc. Way too unlikely.

Re-measure to make sure your water pump housing outlet in not too short, for instance. Or, that you have not installed a grommet somewhere....

Another possibility is that UNDER the water pump, in the L/U, you have installed that base gasket incorrectly and the pump is NOT ABLE to pick up water on it's inlet side. Something of that sort.
Put the muffs on the L/U with the L/U off the motor. Water should come out the top of the water pump outlet from the hose pressure.

And when you do find the answer, please post it. I am very interested in how it comes out.

Good luck."
 
"thanks a lot doug, and yes, m

"thanks a lot doug, and yes, my question was if i could have a crack in the exhaust housing area. from what you're saying, I believe I don't. I don't think my problem is a missing water tube. I don't think my model has one. the coned rubber grommet that mounts on the water outlet on top of the impeller housing pushes tightly into the coned hole that is in the exhaust housing. I will check the other things you mentioned.
sorry guys.. I'm sure this is something simple, and your help is very much appreciated"
 
"Dan,
One other thing I have


"Dan,
One other thing I have done is run the engine with NO lower unit installed.
This is easy on engines with water tubes. You simply hose clamp a 5/8" ID hose to the water tube (where the water pump would normally connect), and connect the other end to the hose you would use with the ear muffs.
Maybe you could rig up some sort of device to press against that conical grommet under there and at least give the motor pressurized water.
Or simply hold the hose tightly against that grommet.
With this pressurized water input, the whole upper part of the motor, block, etc., should fill up with water, and water will definitely exit out the pee hole. If it doesn't...woah. Real problems.

You could temporarily remove the thermostat cover.
Water should gush out of that.

That will tell you if you have a blockage above the waterpump."
 
"let me first say I bought thi

"let me first say I bought this boat last summer and knew I would be working on it this winter. It has been a great learning experience, and I'm not upset at all about what I'm doing. I will try to keep this as short as I can and still fill you in on everything. please respond if you have any input. I was reminded by a friend of mine who drove the boat last summer. I had forgotten that at an idle while in the marina the temp gage would climb some, not dangerously high, but would climb. when I would get in open water and open it up, the temp would drop. clue # 1 that maybe this problem was starting last year.
OK... I still am not sure what is going on, but I do have more info. I used a hose hooked to the bottom of the exhaust housing and water came out the pee tube when I gave it a lot of water. when I only opened the hose a little bit, no water came out. when I looked up from the bottom I could see water coming down from around the outside of the inner exhaust housing. I thought I had a major problem at this point, but found out there is a hole at about the middle of the inner exhaust housing that water comes out of.
I removed the power section then removed the exhaust housing from the boat. one of the eight bolts that hold the power and exhaust together was very tight. I thought I was going to break it, but finally it came loose. It was the bolt that is next to the water hole that goes from the exhaust to the powerhead. this bolt is not sealed and doesn't have o-rings so I thought the inner exhaust housing was corroded away at this point. It doesn't look that way though, because the hole is too clean looks like it is part of the machining. can someone that works on this exact engine verify that. remember this is a 1995 50hp E50TLEOD. I can't believe they circulate water around this bolt, but the hole is too clean for corrosion.
one last thing we found that may be part of my problem. The gasket between the powerhead and exhaust was leaking several places. It didn't look like it was leaking around this water hole I was talking about, but it may have been. also... it was leaking between the exhaust port and other ports in this area. I may have been leaking water here somewhere. This gasket was definately bad. there is exhaust/oil all over this area of the exhaust housing. Has anybody seen this and do you think this may have been cutting down my water flow to the engine. I checked compression before I tore it down... both around 120.
we sealed the bottom of the water tube in the inner exhaust housing and also the little hole about halfway up and filled the water tube up with water, it held the water, so I am convinced I don't have an internal leak in the inner exhaust housing.
do I need special sealer ( like gel-seal II) or is this something I would have in my shop. is there anything special about OMC gasket seal or OMC lock nut, or can I just use mercruiser or other stuff I have here"
 
"Dan,
You have really got her


"Dan,
You have really got her torn down now, huh?
You see what I mean about all the water passages and relief holes, etc. in that exhaust adapter? Water goes everywhere after it leaves that pump outlet.

So, you have verified that the water tube is integrated into the actual inner exhaust housing?
You have NO separate water tube like we all were expecting?

I asked my local 'rude mechanic...the only real help he gave was that he stated that "those three blade impellers really pump the water, don't they?" So, if that is true, you should really be getting mucho water pressure when this is working right. That takes me to the subject of the gasket leaks you found...
The leaking gasket would really have to be wide open for you to lose water pressure enough for the pee hole to not shoot water. See what I mean?
I don't think a leaking gasket would allow enough water thru the leak to reduce your water pressure to the point that you are experiencing.

About the only thing you can do is reassemble ensuring that there are no gasket leaks and see what happens. No much help now huh?

But, OMC Gasket Sealing Compound = Permatex Aviation Gasket Sealer in the bottle P/N 80019, and OMC GelSeal II = Permatex Anaerobic Gasket Maker P/N 51817 (small tube). Both are readily available at your favorite auto parts store. (I hope). JWB, Loctite 518 is now Permatex 51817.

http://www.neverseezproducts.com/permatex1.htm"
 
"doug... thanks for your help.

"doug... thanks for your help. I really appreciate it. I don't know what to do other than put it back together. I have measured on the gearcase and the exhaust housing, and the cone rubber grommet is all that is used on top of the water pump. It is compressed as it is assembled. the opening on the bottom of the exhaust housing is tapered just like the rubber grommet so they come together to make a tight fit.
I am still questioning why water can get to the one bolt at the top of the exhaust housing. can anyone help with that one?"
 
"Maybe the problem is not in t

"Maybe the problem is not in the water outlet circuit...maybe it is in the water inlet circuit.
Maybe the pump cannot pull water for some reason.
Are you sure you have the o-rings installed in the WP housing correctly? The water plate gasket sealed? Put the muffs on the lower unit while it is off the motor and see if water comes out of the WP outlet hole.

Basically, if you put the muffs on, engine off, when everything is assembled, the hose water pressure should fill up the whole system and the pee hole should shoot water.

I would think also that if you took off the thermostat cover, water would come out there too, under hose pressure.

There is an open chamber under the WP where the pump draws from when submerged. I had a piece of gasket fall down there once, and immediately when started, it sucked up against the underside of the WP right at the WP pickup hole. Effectively blocked the input to the pump.

And that impeller is not loose on the driveshaft, i.e. slipping and not turning at the same RPM as the shaft? Is the impeller on upside down? Mine has a top and a bottom. O-Ring (#67 on drawing) is in the groove, etc?

Marine water pressure gauges range from 0-30 psi. So that is the type of pressure you should be seeing...probably around 15 psi. Mine is lower, about 8psi at idle. Rises dramatically as RPM increases.

Make sure #57 is there, and I understand that #62 and #63 you do not have. That is plain weird though.

I am running out of ideas...this has to be much simpler than we are making it!!!

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"Hmm.....interesting.
Here is


"Hmm.....interesting.
Here is the pic of the 1994 Water pump. Seems like you have some sort of year mis-match. Looks like a 1994 L/U on a 1995 engine. There are major differences in the 1994 pic and the 1995 pic.

This pic more closely represents what you have, right? #60 is the conical grommet you are referring to? You know, that really is quite different than anything I have seen....

How did you order the WP kit? Did you specify 1995 50 hp, or did you take the old parts in, and the guy matched the up?

I think you might have the wrong kit. It is very different.

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Scratch what I just said about

Scratch what I just said about different years...etc...I picked the wrong model when looking up the 1995 parts pic. Sorry.

The parts pic is like my second post with the 1994 pic.....for the 1995 model.



Very sorry if I confused anyone.
 
"Three blade impeller is a low

"Three blade impeller is a low pressure impeller and the five blade is high pressure, OMC fitted the three blade impeller to lower the pressure from blowing the thermo off its seat at low speed which caused low engine temps.

Stick the outboard in a tub of water and remove the thermo...run the engine and you should have good water flow if not it could be the water tube grommet closed over in the adaptor plate.
Exhaust pressure also overcomes water pressure"
 
"thanks guys, I wasn't aro

"thanks guys, I wasn't around my computer yesterday, so I couldn't respond. Yes doug, mine looks like the second pic. jamie, if you could, go into a little more detail about where you are referring to the water tube grommet and adapter plate. also... if I had leaks around the gasket (between the powerhead and exhaust housing)I referred to earlier.. could that be an exhaust leak that would stop water flow? also.. does anyone have any input about the bolt that is getting water around it? I referred to this earlier. it is the bolt next to the water passage in the upper exhaust housing."
 
"Jamie...VERY interesting post

"Jamie...VERY interesting post, I am very happy to know about the three blade pressure issue, as well as the "exhaust pressure overcomes water pressure" statement.

Read his story again so far...he has disassembled the whole thing...it has it's foot off, midsection disassembled and powerhead off. This inner exhaust housing apparently has an integrated water tube. NO separate copper tube like I am very used to seeing.
There is not a water tube grommet like we are used to in the water pump outlet. Are you referring to the top of the integrated water tube where it mates with the water plate/exhaust adapter? If so, he has that apart and it should be readily inspectable for the folded over grommet issue.

Ya know, it just hit me...if you had an exhaust leak into the water jacket at the exhaust adapter, and if "exhaust pressure overcomes water pressure", then you could be blowing exhaust into the water system creating exhaust bubbles and air pockets up in the head.

Have you begun assembly yet, Dan?"
 
the crazy thing is that it was

the crazy thing is that it was pumping water before he took it apart............i already was thinking of that on feb 10......its a ways toward the top but he did say it was pumping prior.

im wondering about the wp fit----do you have to fold the impeller to get it into the wp housing? or does it jut fit over the top easily?.........or even the water intake as stated in the above responses.
 
"I have just ordered parts, so

"I have just ordered parts, so I have not started assembly. The inner exhaust housing does have an integrated water galley. the only sealing is that coned grommet that is between the exhaust housing and water pump housing. they fit tightly. at the top of the exhaust housing, the water galley is over at the port side, close to the edge, then goes up into powerhead. the only thing sealing this area is the gasket between the exhaust and powerhead. I have all the blades of the impeller sweeping, as JWB indicates. It is a tight fit. I have to turn the impeller as I insert it into the cup. I was using Lubriplate assembly grease, and thought maybe this is too slippery. what are your thoughts on that?
david... earlier in this thread, I said maybe I had a problem starting last summer. I think I did and this winter started showing up more.
I still would like jamie to give us more input about the grommet and adapter plate. is this the one at the water pump outlet? I had an exhaust leak at the upper gasket also... jamie also referred to an exhaust leak... interesting.
Maybe this is different from what you guys have seen, but I still would love to know why they circulate water around one of the bolts that attach the exhaust and powerhead. the water galley runs right next to this bolt hole and the machining has opened up into this bolt hole. the bolt was almost impossible to get out. the odd thing... there was no sealing anywhere on this bolt to keep water in... but I don't think it was leaking externally.
thanks again for all your inputs... you guys have no idea how helpful all this is. you guys are great."
 
"Make sure part #79 on the dia

"Make sure part #79 on the diagram got installed as shown. Could be upside down.

I had this problem on an old Yammy and after 3 tear downs and reassemblies, I replaced the "cup" and the "housing" although they seemed fine. Worked."
 
thanks.. brandon.... the shape

thanks.. brandon.... the shape of the plate and bolt hole pattern prevents installing mine wrong. one bolt hole is offset.
 
doug... I will receive all the

doug... I will receive all the gaskets tomorrow and will start putting it together. I have everything cleaned and ready to go together..... so no answer yet. I will let you know what I find.
 
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