1987 200 HP Water Pump Install Problem

[bigboat606]

I just rebuilt the water pump on my 1897 200hp Evinrude. I have done this several times over the years. This time when I installed the lower unit and started the engine (on hose w/muffs) I had a VERY weak tale-tell stream and a LOT of water pouring from the upper exhaust ports (the ports just below the powerhead). I let it run for two or three minutes and got concerned when the tale-tell stream never pickup to full strength. I did this (ran it) twice. I noted the powerhead and thermostat temps; one side of the 'V-6' was warm, the other cold. Anyone know what installation error I could have made to cause the symptoms of a very weak tale-tell and excessive water flow from the exhaust ports?

 

[j_k_bisson]

Re: 1987 200 HP Water Pump Install Problem

Nope could not tell you what you did wrong.... Not trying to be too much of a smart ***

But seriously, when you are taking it apart, make sure the grommet in the water out port is seated properly along with the copper tube fits properly. Make sure it is there also.

As to the temp difference, that sounds like you have a t-stat sticking open or one staying closed. You will want to open them babies up and see what is going on in there. Also pay attention to the spring lengths in the free state. it does matter that they are the same lengths. +/- 1/8" Also might be time to change out the Verbatum's (spelling).

 

[daselbee]

Re: 1987 200 HP Water Pump Install Problem

You probably missed the water tube to pump outlet mating. Pull it back down about 1.5 inches, and make sure the water tube goes into the top of the water pump outlet.

 

[bigboat606]

Re: 1987 200 HP Water Pump Install Problem

Thanks. I suspect you guys are right...it is a copper tube related problem or seal the tube mates into. I'll try the suggestion of dropping the lower unit 1.5" and peeking in. I THOUGHT I check the tube alignment carefully, but the shift shaft was a bit difficult to align into it's opening in the cowling and I might of lost sight of the final alignment (after an hour of struggling with it). It will be this weekend till I can get to it. Hope I did not damage the copper water tube if it is mis-aligned.

 

[j_k_bisson]

Re: 1987 200 HP Water Pump Install Problem

If it is bent, just use a round rod or pry bar and slowly work the bend out. I've had to do this to mine when I got it. It seams to be a problem with these motors. But I guess you get that when you man handle large heavy a irregular shape and try to line everything up.....

Been there and have the T-shirt. Be happen you did not squash a finger or two. I seam to always be pinching my sausage fingers when doing this type of work!

 

[daselbee]

Re: 1987 200 HP Water Pump Install Problem

Well, I fired that response off pretty quick, because that is the most common mistake (I guess) that is made when putting up a lower unit. But, I have been second guessing myself, wondering why the engine doesn't overheat, instead of running cold.

No pee stream, water out the exhaust ports.....but it should OVERheat too.

It MIGHT be that you are filling the exhaust housing, and then on up into the powerhead with the water pressure from the muffs.
I bet if you put it in a tank, or the river, that it would overheat quickly.

Hmmmmm. Still thinking. If you discover the error, PLEASE post back what the problem was.

 

[bigboat606]

Re: 1987 200 HP Water Pump Install Problem

I dropped the lower unit down a bit tonight but I couldn’t see the tube/pump mating area, so I dropped it further...too far; the tube end fell out from the pump. The tube was in perfect shape though. I'll try to remount the lower unit again tomorrow if weather permits. This time I'll pay MORE attention to the water tube. As far as the overheating goes, as soon as I started the engine last week I was very cautious with how long I let it run with poor water flow. So I agree, it could well have overheated if I let ‘her go long enough or possibly in the water instead of on muffs. Note that I said one side of the engine got warm. That was my signal to shut down. Was 2-3 mintues normal? Maybe someone can straighten me out; how does the water POUR out of the exhaust ports if I missed the water tube mating with the pump? And while water poured vigorously out of the exhaust ports a low stream came out of the pee tube. So some water was flowing in the head. Are the exhaust ports connected directly to the open area of the mid-section so that if the mid section fills to a high enough level the water will over-flow out the exhaust ports? If that is the case how does water flow out of the ports at high speed and not just run down the mid-section toward the lower unit? What directs water to the ports if the ports are open to the entire mid section?

 

[daselbee]

Re: 1987 200 HP Water Pump Install Problem

I can't tell you or predict how the water will flow if it is not flowing up the water tube, under pump pressure, as designed. No way for me to predict how it will flow if not assembled correctly, etc.

I feel that if the pump is outputting water that is under pressure from the hose/muffs, and (for example) the water tube is not in the pump outlet, then the mid is going to fill up and the water will exit somewhere....just haven't ever done it, so I don't really know what will actually happen.

So, anyway, you have the grommet in the top of the water pump outlet? Are you absolutely sure the water tube came OUT of the top of the pump outlet, or did it kinda flip sideways because it was off to the side of the pump outlet and as you lowered the LU, it flipped over toward center.....
You made sure the o-ring is in the top of the pump body, under the impeller cup? Is everything right with the pump assembly so that the pump itself is not leaking pressure off instead of pressurizing the water tube?

Since you have the LU down, here is something you can try. Get an old garden hose, or some clear vinyl tubing with hose fittings installed, and slide the hose directly onto the bottom of the water tube. Clamp it in place, and run the engine. I bet you will see normal water flow, strong pee-er, and correct temps.

 

[bigboat606]

Re: 1987 200 HP Water Pump Install Problem

You are correct that I'm unsure if the water tube was in the pump housing or not. What I meant to say was that I dropped the LU down too far to know if it was once in or not. I have already ran a water hose onto the engine water tube. I always do this with each pump service to flush any debris. I hope to inspect the pump today and if parts are not required I'll reinstall. I'm sure I've just made a dumb error. I've had this motor for decades, put several pumps in it before and never had a problem. I'm mostly curious in trying to understand how the water flows the way it does in this failure mode. If I get enough time today I'll hopefully solve this.

 

[bigboat606]

Re: 1987 200 HP Water Pump Install Problem

To wrap-up this thread here is the final outcome. I re-inspected my pump service work and could find no error. I re-installed the lower unit and the same thing happened; excessive water poured from the exhaust ports and little water from the tell-tale pee hose. (As previously mentioned I always flush the cooling system with a water hose when the lower unit is removed. To do this I remove the thermostats.) So I next re-inpected the thermostats that I had just re-installed. Apparently I somehow did not properly seat/install the thermostats because when I inspected/reinstalled the thermostats and then ran the engine the water pump began to work perfectly. My problem was an error in the thermostat installation all along.