DoctorJD
06-15-2009, 09:42 AM
Thus far this season I've been dealing with a temperature guage issue on my 91' Conbrio (351 PCM). I started with no reading at all, and now I'm getting readings all over the board. When I started trouble-shooting this thing, I started out with a new guage and now I've replaced the sending unit as well as the wire from the sending unit to the guage. Yesterday, the guage gave me a normal reading for the first time (170-180) and then it started jumping up by 20-30 deg. and then settling back into the aformentioned range. Then it started pegging out, at which point I got nervous and headed back to the dock.
The motor is exibiting no signs of running hot. Even after I got that pegged-out reading, you could rest your hand on the risers comfortably for several seconds. No vapor locking, nothing. Also note that this engine is a salt water version and has a captive coolant system (which is full) as well as a raw water system (still trying to figure this setup out).
Could the wire I ran be the culprit? I just ran a 16-ga. standard stranded wire like you get at the auto shop. Should it have had some kind of high-temp sheathing on it?
Lets play devil's advocate and say that it could possibly be a true reading. The one thing that scares me is that when I changed the impeller out this year, the old one was shreaded. I found some of the pieces, but certainly not all of them. I know the pump was re-installed properly, and I pulled the discharge hose off of the pump long enough to see that water was indeed pumping through it. I tried to see if water was coming out of the exhaust but there's simply too much turbulence back there for me to tell.
However, I keep going back to the erratic nature of the readings. How can it spike 20-30 degrees and then settle back into normal range. This happened reapeatedly until I got that pegged-out reading. I'm at a loss. Any experience with this or ideas at to what the problem could be?
JD
The motor is exibiting no signs of running hot. Even after I got that pegged-out reading, you could rest your hand on the risers comfortably for several seconds. No vapor locking, nothing. Also note that this engine is a salt water version and has a captive coolant system (which is full) as well as a raw water system (still trying to figure this setup out).
Could the wire I ran be the culprit? I just ran a 16-ga. standard stranded wire like you get at the auto shop. Should it have had some kind of high-temp sheathing on it?
Lets play devil's advocate and say that it could possibly be a true reading. The one thing that scares me is that when I changed the impeller out this year, the old one was shreaded. I found some of the pieces, but certainly not all of them. I know the pump was re-installed properly, and I pulled the discharge hose off of the pump long enough to see that water was indeed pumping through it. I tried to see if water was coming out of the exhaust but there's simply too much turbulence back there for me to tell.
However, I keep going back to the erratic nature of the readings. How can it spike 20-30 degrees and then settle back into normal range. This happened reapeatedly until I got that pegged-out reading. I'm at a loss. Any experience with this or ideas at to what the problem could be?
JD