Installing a telltale

[Steve D]

There is an 18 horse listed on the local Craigslist that the guy says, "I also installed a water pump weep kit for a visual aid like the newer engines have." You can see he tapped into the front of the thermostat to do it.

I don’t see a big need for this when operating the motor from the back seat. I just developed the habit of looking back at the water output every once in a while. But if I have the motor hooked up with controls and steering up front I do like to just glance back and see if it’s spitting water.

So is this a good, reliable way to do it? If not, is there an acceptable method of installing one of these? How about earlier years without a thermostat. I vaguely remember some comments about tapping into the top of the cylinder head?

free upload pictures

[crosbyman]

if it works dont fix it.

Joining AOMCI has priviledges 🙂

[Tom]

That seems like a simple way to do it, but… Someone went through all of that trouble to send the stream out the back of the motor, just like the existing stream? If I were that concerned, I’d aim it into the boat!

T

[Steve D]

Yeah I agree Tom, if it’s not shooting to the side it doesn’t make much sense. I’m mostly concerned when steering up front to be able to just look back and see. It doesn’t seem like too much trouble to retrofit something to it like the newer motors have.

[keny]

How about just installing an elbow at the outlet? Then you can point it any direction you please. That’s about what I have on my newer 115 hp.

[fleetwin]

I surely agree, why bother with the telltale if it isn’t pointing off to one side….I don’t think I would bother on an older tiller engine, because I am watching it all the time. Can’t hurt on a remote steered engine though….
On the engine pictured, this seems to be the best/easiest location for the telltale…I would not attempt drilling into the exhaust cover or cylinder head on most engines, you never know how thick the material is or what damage you may cause….The worst case scenario on this engine is simply replacing the damaged thermostat cap.
All that being said, it is important to note that just because the telltale is shooting a great stream of water is not a total guarantee the engine is not overheating.

1 user thanked author for this post.

amuller

[Steve D]

Thanks for that fleetwin!

[seakaye12]

I have a related (sort-of) question that I’ve been meaning to start a new thread for. That’s probably better…..but I’ll give it a shot here….

Are all tell-tales equally indicative of whether or not the engine is getting proper cooling? Are some engines (due to the placement of the tell-tale outlet) going to spit water (assuming the pump and plumbing up to the PH is functional) even though there may be a blockage someplace in the block?

All in all….I would think that the best placement for the tell-tale source would be AFTER the water has passed through the block and has done it’s job….but I’m not at all sure that all engines are set up this way.

Case in point: I just finished working on a Mariner (Yamaha) 8HP that spit tell-tale water like a fire-truck….but the engine was running hot. Salt corrosion in the passages was the cause. Someone relying on the tell-tale on that motor would be in trouble 🙁

[dan-in-tn]

Seakaye12 we will start with your post first. The answer to your question is yes. OMC for years (later years anyway) had their telltale only show the water pump was pumping. It did not show you the powerhead was cooling. Some large engines had the hose coming off the powerhead adapter. It would be rare, but water could never even get to the powerhead.
Now back to the motor at hand. I may be wrong, but if the thermostat worked perfectly (they rarely seal perfectly) then you wouldn’t get any water out the overboard telltale while the thermostat is closed? If this engine has a bypass, then the motor will run cold because you have provided a short circuit around the thermostat? Correct me if I am wrong, but that is the way I see it. You have to be careful where you put in a telltale. If you let water out of the powerhead that is not controlled by the thermostat it is just as problematic as not having a thermostat in the first place.
Mercury does theirs differently on the V-6s, but I am not sure how they do the small motors. They have a poppet valve on big motors. That system does show you hot water after it has been through the powerhead. Both systems have positives & negatives to them.

Dan in TN

[Steve D]

Thanks Dan (and amuller), I appreciate all the good info and knowledge that comes off this site.

[Author]

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