DT40 tell tale issue

[aussiesuzuki]

Hi everyone i recently bought a boat. Its got a dt40 2 stroke probably around the mid 80s. There was no water running from the tell tale, i changed the impeller and still no water. The tell tale was blocked with what looks like white chalky corrosion type stuff, iv cleared it as much as i can and it looks like metal at the end of the hole and i cant clear it out anymore. Could there be a bit of metal stuck in there or is that just how they are. Next time i start it its gonna be in a big tub of water instead of muffs so ill see how that goes.

[Solarman]

Try a piece of thick monofilament line, shove it up the tell tale while running in bucket, or on muffs. If you can get the water to start coming out it should clear itself out. I keep a piece of monofilament handy for all my motors, and use it often.

If still can't get the tell tale going, try running some salt away, or other corrosion flush solution with the foot in a tub, deep enough to cover water pump completely. Run that solution through for a good hour if able. Some times you have to let solution cool if it gets too warm. It might clear the rest of blockage. Make sure each cylinder is cooling down enough, if blockage is not breaking up, you may have to clean out manually, by removing the water jacket cover?

Good luck, let us know how it's going.

[aussiesuzuki]

I started it yesterday in the tub and then with muffs on but still nothing coming from the tell tale. I have been trying to clear it with a piece of wire and even a small screw driver. Is the channel straight or does it curve around at all, (can a screw driver or drill clean it out or do i need something flexible to follow the hole around). Ill try again tonight when I get home but I'm thinking i may have to get some of the corrosion cleaning stuff that you mentioned. I got the boat off my grandfather and it has been sitting in his shed for 3.5 years so this could be why its all blocked up

[Solarman]

No, it is not straight. If it is that blocked up, try a corrosion flush. Otherwise, you'll have to open it up, and manually clean it out. Do you have a good air compressor, you might try using air to blow the blockage clear?

Good luck.

[aussiesuzuki]

I have flushed it three times now with salt-away. I have an attachment that fits onto the muffs. I flushed it for about 5 minutes each time and it still hasn't cleared. I'm going to try and borrow my mates compressor to try and clear the blockage that way. How do clean it out manually? Take the engine apart I'm guessing?

[Moonlighter]

I have flushed it three times now with salt-away. I have an attachment that fits onto the muffs. I flushed it for about 5 minutes each time and it still hasn't cleared. I'm going to try and borrow my mates compressor to try and clear the blockage that way. How do clean it out manually? Take the engine apart I'm guessing?

15 minutes is nowhere near long enough. That is just long enough for a normal flush on a good motor!

I would suggest you get a tub or bin to run the motor in, and either use a concentrated dose of salt away or vinegar diluted 2 water to one vinegar, and run it as long as you can until the water in the tub is quite warm or you think it's too hot. Then allow it to cool, and do that over again 2 or 3 times in the same brew. Run for at least a couple of hours in total. You should end up with noticeable white residue in the bottom of the drum when it settles. Then thoroughly flush with clean fresh water once you are finished.

There is a good article on doing this vinegar flush on The Hull Truth website, Google "Hull Truth vinegar flush outboard" or something like that and you should find it. It was a thread started by THM member MrDemenear. Very comprehensive details there. Has worked well for many people.

Edit: I googled it for you. Here's the link:

http://www.thehulltruth.com/boating-...vinegar.html#b

[aussiesuzuki]

The compressor is already organised so im going to give that a shot tomorrow. The reason iv only ran the engine with muffs and in the tub for 5 minutes or so is because i didnt want to overheat it. Even after running it for 5-10 minutes the motor would be too hot to touch. If the compressor doesnt fix it then ill give the vinegar a go. Salt-away is expensive! $50 for 1 litre! (in australia) and $65 for the bottle that fits onto the muffs.

[Solarman]

I would use vinegar, in a deep tub that goes half way up the mid section, with 6 gals - 8 liters of vinegar (what's available), rest water. Try to run for at least 1.5 hrs (combined time), for add long as you can each time. But it sounds like you have some major blockage inside the channels.

Use the same solution over and over. Can add more vinegar and water if need to keep level up high enough.

Good luck.

[Moonlighter]

It would also definitely be worth checking the thermostat. It it is stuck closed water won't be circulating properly and may be contributing to the propensity for the engine to overheat.

Where are you located in Aus? I'm in Qld, cleveland, just outside Brisbane.

[aussiesuzuki]

Ok an update. I just pulled the leg off and squirted a hose up the water pipe into the motor and voila! Water came straight out of the tell tale. A couple of questions,, if the housing over the impeller is not sealed properly (gasket) could it then not be making enough pressure for the water to circulate properly. I didnt think there was a gasket in it when i changed the impeller out, i could do a silicone gasket on it? And also where is the thermostat located? Iv tried to find it before but i couldnt see it, do these motors even have thermostat? And im located in Perth WA

[aussiesuzuki]

Iv figured out where it was blocked. In between the water inlet and where it comes through to the impeller. I put the muffs on the leg and no water was coming up through to the impeller, when i squeazed the muffs on hard only a little bit would come through. I poured some salt away down it and flushed some through it a few times and got it flowing a lot better. I bolted it all back up, put it in the tub and ran it but still no water coming through. Im going to try it with muffs on tomorrow and see if thats any better. If not ill either continue to flush it in the tub with salt away or ill use the vinegar method.

Thanks for your help guys ill let you know when shes all sweet

[Solarman]

If you had the lower unit off, why didn't you connect the hose directly to the water tube that goes up? You could have run the motor that way also.

Hope you get it flowing.

[aussiesuzuki]

I did connect the hose to that tube and water flowed through straight away. I dont think that it is the problem, it was blocked up in between the water intake and where it comes through to the impeller

[Moonlighter]

If water was blocked from getting to the impeller, and you've run the engine when that was the situation, it may have burned the tips of the new impeller due to being run with no water? Worth a look.