T Stat/Water pump.. Ramification of no pressure relief valves?

J

JohnWI

Seaman
Joined
Sep 14, 2011
Messages
73
1984 EV 70HP

OK..I'm really starting to get into it, even though the motor was running fine, albeit COLD (90 degrees or so). So my plan was to change the thermostat. This is what I find in the process:
IMG_4335.jpg
Looks to me like plasticy gunk on top of the rubber grommet attaching to the springs. No valves. Also hoping no little chunks got into the passages when I had to disassemble the crap! I think I got it all.

So, although I'm going to tackle the water pump at some point (hoping at the end of the season), my question is whether or not have no relief valves in place makes the water flow really easy, i.e did the P.O. or his mechanic, disguise a slow pump with taking out the valves??? It's been running cold, so???

Also here are two pix of the T Stat; does it appear stuck open? I think that it is but don't know how it looks one way or the other (until I get to the stealer to get the replacement).
IMG_4334.JPGIMG_4333.JPG

Thanks Gents!
 
D

durban

Master Chief Petty Officer
Joined
May 27, 2011
Messages
894
Re: T Stat/Water pump.. Ramification of no pressure relief valves?

if who ever has taken the poppet valves out the motor will not get to operating temp , it will run cooler more cold water is going through the motor faster as you throttle up & the combustion \fuel is not as effective if the motor does not run under the heat its meant to, the thermostat spring will be compressed if it is stuck in the open position
 
O

orbanp

Petty Officer 1st Class
Joined
Jun 26, 2011
Messages
324
Re: T Stat/Water pump.. Ramification of no pressure relief valves?

To check the operation of the thermostat put it into a pot of boiling water. You should be seeing it open and close in hot/cold condition.
Looking at your last picture, is there only a third of some white plastic seal around the valve section of the thermostat? It is hard to judge from that picture. Just to be on the safe side, you might as well replace the thermostat.

Peter
 
J

JohnWI

Seaman
Joined
Sep 14, 2011
Messages
73
Re: T Stat/Water pump.. Ramification of no pressure relief valves?

I made it to the "stealership" (I thought that people were happy to get list prices...they actually mark OMC up by 20%) and the mechanic pointed out that what happened was an overheat....the pressure valves actually melted, thus they were now open 24/7.

in my last pic, looking into the thermostat, you can see an amount of clearance on the side of the plunger to the wall.

I bought the replacement parts and I'm hoping I put it all back together right: the pressure valves were installed so the longer portion of the X shape were going into the body and there was an integral washer which will seat into the new grommets. The shorter side was then against the spring/cover assembly.

Also the new thermostat was shorter than the old one and came with a spongy, "rubbery"(not sure if it was rubber it was so soft), washer instead of the cork one that I removed.

I'm wondering if my thermostat was A-OK, and my low temp issue was solely the result of an overheat melting the pressure valves?

Moral of the story: If you over heat...inspect the pressure valves!

Second Moral: Check for even the small weeds as that intake is small!!! I tell you that I have been diligent looking at that tell tale but it only takes a minute to become toast.

I don't know if it was me when I overheated once...immediatly shut down, checked for weeds and restarted but the horn stayed on so I shut it off within 10 seconds (should have read the manual where it says to run up to 2 minutes to see if it remedys the temp which I think was my issue as my water pump is fine [or was fine up until it ran dry...dang weeds]) or a previous owners doing?
 
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