What is the telltail??

[robsd]

I know a dumb question but I'm new to this boat thing. I have a Mercury 110 9.8 and it has one. I haven't gotten it out on the river yet but running in a barrel I get nothing coming out of it. It looks like something has come out of it. I also believe I checked once while it was running and warm air was sort of blowing from it.<br /><br />Thanks,<br />Rob

 

[Pursuit2150]

Re: What is the telltail??

There is normally a steady stream of water coming from the telltail, once the thermo opens, it is sort of a warning sign when no water is visible,there is potential troble.STOP ENGINE. Sometimes they are clogged.

 

[ICEMAN]

Re: What is the telltail??

HIm, If warm air seems to be coming out of it, I would suspect a water flow problem, When was the water pump impeller changed last?

 

[robsd]

Re: What is the telltail??

I just replaced the impeller the other day and haven't run it yet. The impeller had "set" from sitting so long. If I put the shaft in about 20" of water it would pump out of the water line on the side of the engine but nothing from the telltail(before new impeller). I'll try and run it this weekend in the barrel again to see what I get. <br /><br />If still nothing what's my next move? Last time I ran it in a deep barrel the motor ran fine. I ran it for about 10 minutes in gear at half throttle. didn't seem to be overheating. Where does this hole actually go? Water jackets?<br /><br />Thanks for the replies,<br />Rob

 

[almost retired again]

Re: What is the telltail??

Hi Rob,<br />It's quite common for the tell/tell to get cloged. In my part of the country dirt dobbers will clog them at the drop of a hat. Try running a small piece of wire up through the hole if that don't work blow pressurized air through it, you will hear it comming out the exaust. If at htis point you still don't have water comming out of it I would expect water pump problems.<br />Lots of luck

 

[12Footer]

Re: What is the telltail??

A.R.A. has run into the same problem I have in Sunny SW Florida..Those mudawbers will ruin your day LOL<br />Run the pipe cleaner up the telltale, and it should pick up. Do not run it longer than 2 minutes with no flow. You want to make sure the thermostat is opening, but you should get flow by 2 minutes.

 

[skier]

Re: What is the telltail??

Guys, the model he has doesn't have a thermostat. Ther eshould be water after about 30-45 seconds if not sooner.<br /><br />Hope the new pump works and that no damageg was done from the old pump.<br /><br />Craig

 

[12Footer]

Re: What is the telltail??

Merc140, does the 7.5HP have one? I've noticed the clip-on housing for one (looks like a car's master cylinder lid). But it is thermostat-less on my baby merc too.<br />And the symptoms that show-up first on mine, that it's time for an impeller are, it will pump fine at higher throttle settings, but dribble or nothin at idle. And the impeller allways looks just fine. Trust me, change it anyway.

 

[fishhunter]

Re: What is the telltail??

I also have question about my pump... i have a 1979 200hp merc,just bought recently and my first big motor. I noticed when just idling water from tell-tail only spitting a little but at higher rpms a steady stream comes out. Is this normal or could it be a sign of impeller going out? i was warned about the mud dobbers when i store my boat i put a small nail in the hole,if i forget to take it out it will blow out when the pump starts.

 

[skier]

Re: What is the telltail??

12Footer:<br /><br />That depends on what year the 7.5 is. I have a 79 140 and I know there is no thermastat on that model and I doubt that there is on an older one.<br /><br />Craig

 

[Franki]

Re: What is the telltail??

I am curious,,<br />my 100ESL72 100HP Johnson has no teltail..<br />the clostest thing I get is a mist spitting out the exhaust reliefs at the back of the leg..<br />I'd love to have a telltail to give visual verfication of the cooling system function..<br /><br />is there anyway to add one?<br /><br />I can drill a hole in the back of the leg. say a 1/8th hole, and run a host back to one of the hoses running between the thermo housing and the banks of heads (V4) would that work?? would the teltail stream significantly reduce the water pressure ? if so then it would be a bad idea, but if it didn't make alot of difference, being able to see a teltail stream out the back would give me great piece of mind..<br /><br />is it feasable?<br /><br /><br />rgds<br /><br />Frank

 

[robsd]

Re: What is the telltail??

Ok I dropped the engine in a bucket last night with water just over the cav. plate. Water started comming out of the water pump hose in a second so the impeller change out went fine. The only thing comming out of the telltail is exhaust. It just looks like it's open to the lower unit. <br /><br />Is water coolant supposed to come out of 2 places on this thing?<br /><br />Thanks,<br />Rob<br /><br /><br />On Edit: It's not running hot. Ran it for about 4 minutes.

 

[Waco]

Re: What is the telltail??

I would like to hear some comments about Franki-ESL10072's question. Is this possible?

 

[Franki]

Re: What is the telltail??

yeah, me too <br /><br />I have added a temp guage, and fixed the warning horn, but I can't help thinking that if I had a visual stream to watch, I could react instantly if it stops.<br /><br />rgds<br /><br />Frank

 

[butlp]

Re: What is the telltail??

Franki-ESL10072 and Waco,<br />Instead of drilling holes to install a telltail, why not install a water pressure gauge in your dash. There is lots of information about installation on this forum. <br />This saves you getting a stiff neck from constantly turning round to see if you have any water coming out of the telltail.

 

[Franki]

Re: What is the telltail??

putting a peehole in would be far easier and cheaper then installing a guage..<br /><br />Also, I have just added a temp guage.. and it was a pain to run a new wire all the way along the boat and still have it look factory.. and its even worse with the pressure guages I have seen as they require that you run a plastic tube all the way forward to the dash, and the air in that tube is what determines the pressure, the tube on an outboard can't be considered that reliable since they were designed to be in a stationary situation (like in a car) an outboard moving with steering is hardly stationary..<br /><br />I just wanted to know if anyone has tried it.<br />(and if it worked.)<br /><br />rgds<br /><br />Frank

 

[tajones]

Re: What is the telltail??

Franki-ESL10072, Most tell/tells are at the top or very end of the circulation. In other words, I think you idea will work, but make sure you are at the end of the circulation and that all engine areas have recieved water for cooling before the it comes out the pee hole. I'm not sure why you need pressure if water is pumped to the engine form the shaft pump, so your idea should work. But I'm no expert,<br />Jabo

 

[butlp]

Re: What is the telltail??

Franki-ESL10072,<br />You do not have to use a bourden tube type of pressure gauge even though they are the most common and the plastic tube will last as long as the wiring harness on your outboard.<br />An electronic gauge and sender unit can be installed and you only need to run one wire as long as you have a good ground at the dash. You can buy them from most gauge manufactures and auto supply stores.<br />My concern with the telltail is you have to be watching it all the time to be really sure you everthing is OK.<br />I purchased a boat with a blown 235 OMC that had picked up a plastic bag at WOT. When I rebuilt the motor I installed cyl. head temp gauges on each bank, water pressure gauge and also a low water pressure switch connected to the control horn. As soon as water flow stopped the horn went off and it saved the motor a couple of times. If I had relied on the telltail, I think I would have been rebuilding the motor again. This was offshore Dubai where there seemed to be a lot of garbage and plastic in the water.<br />Hope this helps.

 

[Franki]

Re: What is the telltail??

my cheapness often brings out the Maciver in me...<br /><br />I wanted to add a thin cylinder to the front of the cover, with one end blocked, and the other running to a tee piece in the cooling system,, then put a close fitting red ball in the tube and a spring behind it..<br /><br />the idea being that water pressure would push the ball up to the top, compressing the spring. and if the ball wasn't at the top, then the pressure wasn't good.. (course you'd have to play with spring tension)<br /><br />I didn't care if the indicator is on the dash or on the outboard cos I spend most of my time stressing about the motor and watching it..<br /><br />If I added a peehole, I'd try to make it shoot up into the air behind the boat, so a glance back would see it easily without running to the back of the boat and trying to see water coming from the relief holes.<br /><br />I was just toying with possible answers, but if a water pressure guage is whats needed, then I guess I'll have to go and price one.\<br />(the electric temp guage I just installed cost me about 70 dollars, (VDO),, hoping the water pressure will be less, but I doubt it.<br /><br /><br />rgds<br /><br />Frank

 

[Franki]

Re: What is the telltail??

Actually, I just had an idea on the peehole idea.. <br /><br />on modern cars the window squirters have tiny adjustable heads, and they have a tube fitting on the inside.. <br />put one of those facing up on the back of your leg and direct the outlets backwards..<br /><br />you'd have to fine jets of water spraying slightly up and backwards of the boat, easy to see, and if you decide you want it pointing down later, you can just spin it around..<br /><br />its an interesting idea.. and it appeals to my "unique ideas" preference. <br /><br />I am going to try it,, even with a water pressure guage, I'd still like it.. I never really entirely trust guages over what I can actually see myself.<br /><br /><br />rgds<br /><br />Frank