Is it hot?

[jimmyz1]

Well I took my boat/motor '87 merc. 60hp 3 cylinder out today. I know from doing seaches on here folks say the pee stream water should be warm. I tested mine after running a while and could hold my hand under stream for about 5 secs. before it became uncomfortabe.

I do have a strong stream coming out. Motor ran great but I headed in after feeling that hot water. Started fine both when cold and after i noticed it hot. Passenger side of cover much hotter than driver side when i put hands on both. Questions:

Should one side be hotter than other?

If hot, how hot would it have to be to do damage? and would motor still run perfect like nothing is wrong?

I had no alarm that I heard. Anything I can do to make sure everything is open and not clogged?

Thanks. Hope I gave enough info. If not please ask.

Thanks again.

 

[jimmyz1]

Re: Is it hot?

Tad bit more info. I put it on muff's when I got home and it seemed fine. Ran if for over 10 mins. I was practically taking a bath in it. Neighbor's must think I'm nuts. Am I? Water never got as hot as it did when I was running it on the water.

Thanks

 

[hkeiner]

Re: Is it hot?

I tested mine after running a while and could hold my hand under stream for about 5 secs. before it became uncomfortabe. I do have a strong stream coming out.

If you want to monitor the cooling system's vital signs more precisely, you have several choices. These include installing a temperature gauge, using a hand held IR thermometer, using a temperature stick, or installing a water pressure gauge. Below are a few links that may help you decide.



http://www.iboats.com/Thermomelt_Te...8555994--**********.806358773--view_id.366448


http://www.google.com/products?hl=e...&lnk=pruser&hl=en&price1=20&price2=30&btnP=Go


http://www.diy-boat.com/index.php?option=com_content&task=view&id=151&Itemid=49

 

[emckelvy]

Re: Is it hot?

Your motor is definitely running too warm. The exhaust cover (pssgr side which is what I assume you're feeling) should run cool to luke-warm at best. The water coming out of the telltale should not be uncomfortably warm.

Your motor doesn't have a thermostat (at least according to this diagram, which is supposed to be for an '87 60 HP):

http://www.mercruiserparts.com/Show...36&bnbr=100&bdesc=Exhaust+and+Manifold+Covers

So there's no reason for it to ever get hot, or even very warm.

I'd pull the lower unit and inspect the impeller/water pump. Hopefully you don't have a chunk of impeller blade busted off and up the water tube, blocking flow.

To verify this after pulling the lower unit, run water from your garden hose up the copper water supply tube. Just use a hose clamp to tighten down a chunk of hose over the water tube and hook that up to the garden hose.

You should note a strong stream out the telltale, and lots of water dumping out the mid-section (exhaust tower).

It's possible that your motor has been silted-up, and if you note poor flow thru the powerhead you'll need to remove the cyl block cover (the one over the spark plugs) to check for blockage in the water passages.

If you end up doing this, use caution when removing the cover bolts. If they won't come loose with normal force, get a propane or MAPP torch from Lowe's Home Depot etc and heat the bolt up to break it loose.

Run water up the motor with the cover off and note flow. Depending on what you see, further teardown may be required.

Hopefully, it's just an issue with the impeller. Definitely don't run it until you address the problem. BTW these motors are already 'running on the edge' and should have the water pump serviced/impeller replaced every year.

Since it sounds like you were pretty cautious about running it warm, and you caught it early, it's Most Likely no damage was done. If you'd let it go to the point of overheating with steam etc, it would be Toast!

A compression check will give you a good idea of the condition of the innards. An inexpensive automotive gage would work for this motor, since there's easy access to all spark plug holes.

To do a compression check, pull all the spark plugs; place the control box at full throttle; and with the key off, jump the positive terminal of the battery (or the Hot battery lead on the solenoid) to the terminal on the starter motor's solenoid where the yellow wire is connected. Watch out for the prop 'cause it's gonna turn! Crank until compression gage stops moving. Note reading and repeat.

If you have a good, tight motor, values will be within 5 psi of each other. Expect problems with variances of 10 psi or more.

HTH & let us know what you find..........ed

 

[emckelvy]

Re: Is it hot?

OK, so I was working on the above post when you posted about running on muffs.

So it runs cool with no load out of the water. However, best monitor very carefully when in the water with a load. Naturally the motor won't generate as much heat when on muffs at idle with no load. Not to mention you're putting lots of water pressure into the motor.

If you had a marginal impeller it might circulate plenty water being supplied by muffs, but it's a different thing when in the water.

I'd still be inclined to pull it down and check the impeller, but if you feel the need to run it again, just be very cautious and don't run at higher-power settings until you're sure it's cooling properly...........ed

p.s. if you don't know how old the impeller is, it's time to replace it!!!!

 

[kellyisu]

Re: Is it hot?

I'd deffinatly check that impeller. My motor was not showing any signs of a weak tell tail but one afternoon it started to kill after it was warmed up (I had no alarm). Tell tail stream looked good(actually real good) but same thing, I had very hot water in the stream. I pulled the lower unit and sure enough the impeller was chewed up. I was fortunate not to have damaged anything.

 

[thefairlaneman]

Re: Is it hot?

As a general rule to me is if the impellar hasnt been changed in 3 years of normal use its time to replace it or at least take it apart and be sure its not dryed up cracked/burned up etc.

 

[kellyisu]

Re: Is it hot?

Yep- about the same here, about every other year, but in my case this time I had just purchased the motor used and only had it out a few times and failed to ask when it had been changed last when I purchased it. I agree though, many people change them every year. I really have to watch mine because I use my boat on the river more where more sand is prevelent to wearing on the impeller faster.

 

[jimmyz1]

Re: Is it hot?

Thanks guys. I will be replacing the impeller for sure and go from there. Hopefully that's it. I will post results when complete. If I have any issues I will be sure to ask.

Thanks again.

Jimmy

 

[jimmyz1]

Re: Is it hot?

Well I took it to a shop nearby since I did not have a repair manual. He put a temp. gauge on it. Top cylinder at 190 degress. Lower 2 at 180. All normal and good according to him. Pulled lower unit, impeller and everything looks good. He said water is getting throughout motor.

I guess I'm just worried about nothing. I need to quit looking for problems and just enjoy my motor and boat.

Thanks guys.

 

[hkeiner]

Re: Is it hot?

Worrying about an overheating motor is being wise and prudent. Overheating is one of the most common causes of major engine failure, quickly turning a running motor into scrap. In your case, there may not have been a problem, but checking it out was the right thing to do.

 

[kellyisu]

Re: Is it hot?

Yep, better safe then sorry$$$ It's good your getting to know what's normal for your motor. Did ya have a new impeller put on while he had the lower unit off anyways?

 

[jimmyz1]

Re: Is it hot?

No. He said it looked great. He also answered ? 's I had about a few other things. So at least I know more about the motor.