How to unplug tattle tale.

[Rayzor]

I bought a Merc 500 50 horse (1967). It starts and runs perfectly but was not throwing any water stream out the tattle tale. So I just replaced the impellar and tried and tried to get the line to blow threw. The old impellar was not in terrible shape and had not come apart inside. I tried flushing water threw the pick up tube and used wire and such to dig at the plastic fitting that comes out of the power head. Could not get compressed air to blow threw. Whats the next step to take, not in a hurry just trying to get it all snuffed up for spring.

 

[Lone Duck]

Re: How to unplug tattle tale.

I bought a Merc 500 50 horse (1967). It starts and runs perfectly but was not throwing any water stream out the tattle tale. So I just replaced the impellar and tried and tried to get the line to blow threw. The old impellar was not in terrible shape and had not come apart inside. I tried flushing water threw the pick up tube and used wire and such to dig at the plastic fitting that comes out of the power head. Could not get compressed air to blow threw. Whats the next step to take, not in a hurry just trying to get it all snuffed up for spring.

Is there a temp sender in the water cover or a plug for one ? If so, I would screw that out and look for blockage. If not ,pull water cover.

 

[Rayzor]

Re: How to unplug tattle tale.

Water cover and or temp sender. Where would these items be located? Im kinda new to mercs.

 

[Maxz695]

Re: How to unplug tattle tale.

The temp sensor or brass plug would be on the rear cover where the spark plugs are. Unscrew it and try to flush it again through the water tube. If no water then there is blockage and I would start at the Thermostat if your engine has one. The exhaust cover would be next to be checked and then the exhaust base plate. (Powerhead removal required for that). Start with the easy inexpensive things first. If there is water coming out of the hole in the rear cover where you removed the brass plug then there is blockage at the fitting leading out to the tell tale of the rear cover, or in the tell tale and or hose to the tell tale

 

[Texasmark]

Re: How to unplug tattle tale.

The '67 was based on the old '40's 4 cyl design which started out as 25 hp back when the cowl was green and the name was Kiekaufer (spelling??) and migrated up to the Mercury Mark 55 at 40 hp emerging in the '50's. Back then there was no pee and no stat. So you sir are chasing a ghost!

The pee is routed, on the later model engines I have been around, either from the exhaust manifold cover, the top of the block, or the output of the thermostat.

On the non stat ports, it is available as fast as the water pump can fill up the powerhead with water. On the stat output it isn't available until the stat opens (143F) and at cold operating temps comes and goes as the stat opens and closes keeping the powerhead warm.

Mark

 

[Rayzor]

Re: How to unplug tattle tale.

The '67 was based on the old '40's 4 cyl design which started out as 25 hp back when the cowl was green and the name was Kiekaufer (spelling??) and migrated up to the Mercury Mark 55 at 40 hp emerging in the '50's. Back then there was no pee and no stat. So you sir are chasing a ghost!

The pee is routed, on the later model engines I have been around, either from the exhaust manifold cover, the top of the block, or the output of the thermostat.

On the non stat ports, it is available as fast as the water pump can fill up the powerhead with water. On the stat output it isn't available until the stat opens (143F) and at cold operating temps comes and goes as the stat opens and closes keeping the powerhead warm.

Mark

So your saying my motor should not have a pee tube? Im a bit confused, looking at the back of the motor facing the spark plugs, there is a plastic fitting with a 3/8 tube coming out on the lower left just behind the exhaust cover. It routs a tube over to the lower cowling where it connects to another fitting that appears to be a pee hole. What exactly is this tubes function if not a tattle tale? I asume the new impellar is working properly as there is a fair amount of water spray coming out the upper exhaust outlet. Not pouring, just spray at idle while in the water barrel.

 

[carholme]

Re: How to unplug tattle tale.

Rayzor;

That plastic fitting is your pee tube. Your engine does not have thermostat and unless someone has modified it for a temp sender, it will not have one of those either.

Parts listing:

Mercury Parts, MERC 500

Here is a link to the condensed version of the Clymer service manual. Download it soonest to your computer as the link is short lived.

Small Engine Repair Reference Center Home

Gerry

 

[Rayzor]

Re: How to unplug tattle tale.

Thanks for the link, I have a seloc manual but it cover 30 years of different mercs so it kinda just a guide.

 

[carholme]

Re: How to unplug tattle tale.

Should you want it the OEM manual for your engine is P/N: 90-68647, but it too covers all models from 1966 thru 1974.

mercury outboard service manual 90-68647 | eBay

Gerry

 

[Texasmark]

Re: How to unplug tattle tale.

So your saying my motor should not have a pee tube? Im a bit confused, looking at the back of the motor facing the spark plugs, there is a plastic fitting with a 3/8 tube coming out on the lower left just behind the exhaust cover. It routs a tube over to the lower cowling where it connects to another fitting that appears to be a pee hole. What exactly is this tubes function if not a tattle tale? I asume the new impellar is working properly as there is a fair amount of water spray coming out the upper exhaust outlet. Not pouring, just spray at idle while in the water barrel.

Ok, disinformation on my part. Apologize. Too many years ago and too many models.

Mark