Tell tale on 1998 Mariner / Mercury 135 V6 not peeing on muffs

[kwik_uk]

Hi guys,

Finally got my new second hand outboard mounted up on my project (see sig).

Started up no problem. I flushed water through it before starting at both the lower unit with the muffs, and from the cowl fitting using the hose adapter.

After about 5 minutes running at idle with the occasional rev, I still can't get it to pee water

Heads are hot, just at the temp where they're too hot to hold your hand to for long. I disconnected the hose that links the two thermostats together and there is no water passing here. In fact the hoses were dry. Tried to remove starboard thermostat housing but the bolts are in solid. So much so one actually snapped Housing is still secure, and sealed, so I don't want to disturb it unless absolutely needed.

I've tried searching though the forum for previous posts on this topic, however the replies seem to be mixed. Some say it won't pee at all on the muffs, others say it should pee in 10-90sec

I can't get it in the water just yet, but if I lower the lower unit into a large tank of water (there's one at the marina for just this use) will it then be more likely to pee?

There was water coming out of the area above the anti-ventilation plate where the lower unit anode is. So I guess it's actually pumping water ok? I also tried disconnecting the hose from the port t/stat and blowing/sucking, and there was no movement, which leads me to believe that the t/stat was closed?

Previous owner gave me the usual "just been serviced" but in this case I think he was genuine. Motor otherwise was in outstanding condition.







Any advice would be greatly appreciated!!

Thanks,

Mark.

[starkyb]

I had the same problem with mine. It always peed when in the river or the lake but wouldn't pee with muffs. Believe it or not I bought some new muffs and now it pees like a race horse in the driveway. Try some new muffs and give it another shot. I don't know how you put them on but slide them on from the back.

[kwik_uk]

I had the same problem with mine. It always peed when in the river or the lake but wouldn't pee with muffs. Believe it or not I bought some new muffs and now it pees like a race horse in the driveway. Try some new muffs and give it another shot. I don't know how you put them on but slide them on from the back.

How strange! It's really got me confused. Not sure I can slide the muffs on from the back as it will foul the prop

The muffs in using are older than me, but I figured they'd still do the job? They're the old round ones, rather than the newer style oblong units:



Do you think trying it in the test tank would be worth a shot? I don't want to risk any damage if there is actually an issue I'm not experienced enough to spot. If I do run it in the tank, I'll take my infra red temp gun down and measure the blocks for temp. I think I read somewhere that the t/stats should open at 140 degrees F?

[starkyb]

Looking at your pictures I realize your intake holes are further back towards the prop. I would try it in the tank. Give a few seconds and don't rev it until you see a good stream.

[GT1000000]

Yep, just popping in to see what's up, but DEFINITELY DO NOT run it without the telltale showing good flow...you can overheat and ruin the engine in no time...

When you hook up the muffs, you should get flow from the pee-hole within a minute or so, of start-up if the engine is equipped with a thermostat...it could very well be that the thermostat is not working or there is a blockage in the cooling system...this must be remedied!

One of the gurus that I mentioned should jump in here and point you in the right direction, if not PM one of them and see if you get a response...it is extremely important that this part of the engine be working flawlessly...

"Clams Canino" or "faztbullet"...

Hope you get it figured out...

[kwik_uk]

Cheers GT. I'll PM them now, and see if they've got a few minutes to help

[narvlebenoit]

Put it in a garbage can or tank I have a 90 mercury that wont pee on ears tans or the safe way.

[juplie]

How strange! It's really got me confused. Not sure I can slide the muffs on from the back as it will foul the prop

The muffs in using are older than me, but I figured they'd still do the job? They're the old round ones, rather than the newer style oblong units:



Do you think trying it in the test tank would be worth a shot? I don't want to risk any damage if there is actually an issue I'm not experienced enough to spot. If I do run it in the tank, I'll take my infra red temp gun down and measure the blocks for temp. I think I read somewhere that the t/stats should open at 140 degrees F?

I recently had no water coming out of the tell tale so i removed the rubber hose and used my compressor to give a shot of air into the line and tada after hooking everything up water started to pee out the telltale.

[Chris1956]

Many V6 Mercs will not have a telltale until the thermostats open. When running on the flusher, in neutral, the motor may not warm up enough to cause the 'stats to open. If you can find a barrel, I would run it at idle, with my hand on the heads and see if the telltale emerges. If the heads get too warm to touch for a few seconds(with your hand), it is overheating, so shut it off.

If it were me, I would use some heat to loosen the thermostat bolts, and then use an impact driver to loosen the bolts. I would then replace the 'stats.

[kwik_uk]

Thanks for the replies guys.

I used a large barrel instead of the flusher, and the tell tale would still not flow at idle, even after about 5 mins of running. Heads were hot to the touch. A drop of water won't sizzle on it, but it's too hot to keep your fingers pressed against for longer than about 3-4 sec. When the motor is revved, the tell tell starts to work, and the heads cool

I took the top hose off between the two thermostats, and when I give it some revs water will exit from the port thermostat, so I'm guessing that it's open. I then try and blow down the tube to the other side and nothing, feels firmly shut.

As soon as I back down off the revs the tell tale stops, and the engine starts to heat up again. I've found out that my port temperature sensor looks knackered as it isn't sending a signal to the gauge (I've tested the gauge). So I'll need to order one of these too.

I took the lower unit off and the water pump, impeller, gaskets and plate are all new as the seller had promised.

I'm going to need to go out and buy an impact driver as I can't for the life of me remember where I put mine

Would you say it would be best to apply heat to the head or to the bolt in this case? I don't want to damage any other components or seals.

[kwik_uk]

Removing the thermostats. That in theory is easy. Four bolts out and you can inspect. First bolt I tried to loosen snapped with next to no force on it. Bummer.

I moved on to the other bolt and heated it up with a blow torch before using an impact driver to remove it. No problem, came out great with a good bit of heat. You can also see the snapped bolt in this one and a whole host of crud and salt!!



Using the blow torch and a stud extractor I managed to get the remains of the offending bolt out. Thankfully it had snapped about 2-3mm from the top of the bolt so it gave me something to grab on to.






Do you guys think these thermostats need replacing?? LOL






A friendly chap I know gave me a thermostat to try, unfortunately is was the wrong one. The one in the middle is one I cleaned up just to see if it would pop in boiling water. Needless to say it didn't! heh
I'm going to order two with seals and gaskets in the morning. Should have them ready to install on Thursday night.




It also needs a new temperature sender (port side) for the gauge. Tried testing it as per the factory manual but it is 100% dead.
So all in all not a bad night's work. I'm looking forward to fitting the new parts and firing her back up!!

Thanks for the help so far guys, really appreciate it! I'm slowly but surely getting to grips with this newer style engine over the old Tower of Powers I've ran in the past.

[narvlebenoit]

they look bad see why it was not peeing good luck with new ones.

[aussieflash]

Know how you feel.Dont forget to clean up port area and stat cover.I also flushed hose down stat ports with lower unit off and placed bucket underneath and collected a fair bit of debris like shells sand and salt chunks etc.
Good Luck.

[444]

FWIW, my 1982 175hp v6 does't pee worth a darn on the muffs. Might spit or dribble a little and that's it. I was alarmed because my 84 90hp inline 6 would pee water like a garden hose. Threw the 175 in the water and it pees, albeit not near as strong as my old 90 horse did. Have heard this is common with the merc v6's. Also my 90 horse didn't run thermostats so that may be a factor.

[Chris1956]

You might chase the thermostat cover threads. Use some permatex #2 on the thermostat bolts. Chase their threads or replace them.

[kwik_uk]

I got this sorted in the end. New thermostats, cleaned the threads and bolts, re-assembled and voila! Peeing after about 10secs!

I've had the boat out since then, videos are in my resto thread in my sig if anyone wants to see

Here's one of it running (and peeing!) on the muffs: