DT115 water pump

[dj_movers]

I have a water flow issue with my 1986 DT-115. This thread is similar to Kiwi's thread. The water impeller was recently changed by my mechanic. I also replaced the water flow sensor.

Somewhere during a trip, the water at the tell-tale hole stopped flowing. I figured it just got some salt clogged in the tell-tale line. Cleaning it with a wire did nothing. Since the alarm did not come back on (it works at start-up) I kept going. I ran at top speed for 2 hours. When I got home on the earmuffs I could not see anywater coming out ANY outlet, ie., the water pump does not appear to work at all and the alarm is sounding constantly.

I am confused, because if it was not getting any water, I would guess I would have burned the motor up by running it hard for 2 hours.

Any thoughts?

[Vitamansea]

Impeller

Did you bend the impeller tips in the correct direction? When I lift the zuki powerhead off there is a little cavity at the telltale, a piece of gasket or sealer gets in there and you have no telltale. I usually find a piece of the old impeller stuck in the system somewhere.

If you're overheating and have no telltale a few other conditions could exist;

You have no woodruff key on the shaft for the impeller to lock into.
Your pick up tube is not connected or the gasket is missing.
Your thermostat broke apart and is blocking waterflow.
You have the wrong water pump gasket set installed

I see your mechanic did the work, Im sure you consulted him. Lucky for you it takes 10 minutes to drop the foot and check the waterpump set up.

[dj_movers]

Hope to drop it later this week and have a look. I will post back with the findings.

The thermostadt is known good, however, your other the points are real possibilities.

I am turning the wrenches from now on...

[Solarman]

First off, it is a temp sensor on the dt motor, not a flow sensor.
Second, kiwi's motor and yours may be similar, but each motor is different an often that thought can confuse issues.

Let us know what the impeller looks like, if fragmented/ in pieces, someone probably turned the motor over when dry. Doesn't take but couple seconds to eat an impeller if dry
If in good condition and key still in place, make sure the water tube grommet is in place and good.
Also, look at the mating aluminum webs where the midsection and foot bolt together, if corrosion has eaten the webbing it needs to be repaired. That webbing separates the exhaust chamber from the water pick up chamber. Exhaust pressure can stop water from getting to the water pump. There is a sub-water pick up tube that goes through the exhaust chamber, there are grommets at both ends, what do they look like? They are under the water pump impeller housing, if burned or not sealing, they have to be replaced, the heat shield under the water pump has to protect that grommet under the water pump.

We need to know what you find in all this above, there are other things to check before putting back together/ while taking it apart, no need to do all this twice.

[dj_movers]

OK, thanks! I hope to drop the lower unit later this week. The impeller is probably damaged.

The DT115 does, in fact, use a water flow sensor. It was poorly designed and needs to be replaced about once a year. Suzuki Outboard - 34870-94630 - Cooling Water Sensor

Thanks for the reply!

[dj_movers]

Update time: I have dropped the lower unit and made pictures. Nothing seems wrong to my untrained eye.

1. The woodruff key is in place
2. It is the correct P/N for the kit
3. Sub-water pick-up tube is clean
4. Impeller fins are curved in the correct direction
5. The impeller has a couple of very minor shreads on cover side (see picture)
6. Two of the four impeller cover bolts were only hand tight
7. One of the four bolts was a wrong part, but appeared to be a suitable replacement
8. I have a new kit, but see no reason to use it since the installed one is new and looks OK to me

That's where I am at today. Anything else I should do before reassembly? Thanks!

[artdf175]

good pictures
the parts diagram does not indicate a gasket between the impeller housing and the panel plate
However I don't like the looks of your impeller
it appears to have been run dry which subsquently appears to have burned the upper surface .. jeorodizes the intigraty of the unit
also, the parts picture may be inaccurate, but the fins are not distorted on the diagram where your picture there is a good inflection in the blades
If yours did get damaged in running dry for a short period it may not be pumping very well
also with the bolts not torqued correctly, you could very well be losing a lot of water out the sides.. and would find the right bolt..
one last suggestion.. clean up the surfaces where the gaskets mate
and in my manual for most gaskets, they do not reccomend reusing old gaskets
and understand your comment about turning wrenchs - been there with a local dealer myself
good luck and keep us posted
Art...

[dj_movers]

Art,

Thanks for your reply. Here is a picture of the actual impeller fin distortion. The service manual does not have a picture to compare.

David

[Solarman]

dt115, water pump issues

You mention the sub water pick up is clean? Did you inspect the grommet under the housing? From your pic it looks like someone has used epoxy on the housing eatery passage? How does the webbing of the mating surfaces look? Can you post a couple pics of the exhaust side of the pump?
Keep us posted.

[dj_movers]

OK, here are some additional pictures I took today. The patch is more like a silicone sealant. I am guessing someone did that to enhance a worn grommet. Whatever it is needs to be redone. Regards,

[Solarman]

dt115, 1986, water pump flow problems

Ok DJ, the silicone sealant does nothing where it's at. Under the sealant should be a stainless plate (heat shield) that protects the grommet around that stainless tube (sub water pipe). If you shine a flashlight into the passage where water comes up to the pump, you can see the end of the sub water pipe with the grommet around it. If it looks shriveled, or burned and loose then it should be replaced. Before taking anything apart you need to clean the silicon off. See if any reason for the silicon (plate damaged, our missing?).
If you need to remove that plate, get the parts you need first. There should be an oring for the bearing housing, and the grommet for the pipe end, and you might need the screws for the bearing housing (under the stainless plate where the impeller goes). There is also a grommet on the other end of the sub water pipe. Be careful loosening the screws, it is an older unit, don't need to break any off. If the 4 screws holding the bearing housing are tight use an impact (w/proper bit) to loosen. Don't want to break any either. If all loosen ok, and in good shape, no need to replace them.
If you don't need to remove it let us know. If you do let us know, once you have parts needed. The bearing housing has a drive shaft seal (replace if need to remove). This housing seals the lower unit, do not remove unless ready.
Also, show us a pic of the midsection where the lower unit mounts. Need to see the webbing.
Good luck let us know.

[dj_movers]

OK Solar, here are some more pictures. I do not know what is meant by webbing. Thanks!

[Solarman]

The webbing is the aluminum surfaces that go from side to side. Each one of those sections is a separate chamber. The exhaust is the section with the large round hole in it. The water pump chamber is next one towards the front of the motor. The webbing has to match tightly to the webbing on the lower unit when bolted together to prevent exhaust gases under pressure from interfering with the water pump trying to pull up water in the next chamber over. The sub water pick up helps to force more water into the water chamber during higher speeds. So if the exhaust is leaking enough through those grommets it will push water back out and prevent water flowing into the water pump, so the water pump pulls the exhaust, not water.
Your webbing looks pretty good, may be one small place in the middle, can't tell if corroded away, could be discolored aluminum. If it is eaten away, a little 5 min aluminum suitable jb weld will fix it. Put a little masking tape on the smooth surface of the webbing, mix a dab of epoxy together till warm (have edge surface speedy cleaned good), smear a good coat to fill it in, wait 5 mins, remove tape. If you did a good job the mating surface should be clean/ fine, and could last another number of years.
Let me know if any questions.
And let me know before proceeding with removal of bearing housing if needed. You need wisdom before attempting.
Let us know what's up.

[Solarman]

dt115, water flow problems

Haven't heard from you. Everything still in limbo? Have you done anything?
Post what's up.

[dj_movers]

Hi Solarman,

Thanks for asking. Here is an update. I have been on hold while the lower unit is in the shop to have an unrelated crack welded. I was supposed to get it back Friday, but did not because the guy's welder is broken. Hopefully, I will get it Monday.

I ordered a new water pump cover bolt to replace an incorrect part. It arrived Friday. I am going to clean the old bolts today so they will be ready.

The dark spot you saw on the webbing is actually a U-shaped slot between the chambers. Right now, I am not planning further disassembly. Probably next step is to clean, reassembly and test in water not earmuffs. I really don't see any problems. I am not sure whether or not to use the new water pump kit since this one only has 2 hours on it.

I started a big stink on another blog about whether to use grease or anti-seize compound on the lower unit bolts. The majority voted for grease...

Regard,

David