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TAMD 31P temp alarm issue

tzieli22

New member
I started a thread 2 years ago about an issue with engine oil blowing out on my dipstick tube. After two seasons, that issue has never returned. This said however, since this issue, I had one of my raw water impellers break apart (in the same engine as the oil issue) and now I am on my 3rd season with this issue;

engine temp alarm goes off once I hit about 180 (which is my thermostat temp) and will trip off/on when running about 3200 rpms or more, but my temp never hits higher than say about 190 but the alarms is going off constantly. I have replaced the thermostats, flushed engine coolant, cleaned heat exchanger, cleaned out my transmission cooler, and oil cooler. Also replaced heat temp sending unit, cleaned and checked the small tubes that go into the coolant reservoir from the thermostat and turbo housing. And I swapped my temp gauges to make sure I didn't have a bad gauge.

I am out of options... Any help or tips on this? Thanks.
 
Not sure about your engine, but some engines have both a temp sender unit and a temp alarm sender unit (i.e. 2 sender units). Check your engine and see if it has a 2nd sender for the alarm.
 
This engine has two sending units. One with solid colored wire is for the gauge, one with tracer wire is for the warning panel. Most likely your warning panel in the dash needs to be checked, might be corroded connection giving signal too early. Does pressing Reset button on the dash quiet the alarm?
 
You might look at corrosion in the harness connector in your engine bay. I ended up cutting the connectors out and permanently soldering the connection together.... It solved all the guage glitch issues. It could also be a weak ground
that might be a contributing factor. Not sure about this but see if there is any teflon tape on the sender threads, they are not supposed to be coated / insulated with tape. Finally depending on the history of your boat there is a chance the sender is a automotive look alike. I had this similar issue on a oil pressure switch which in my case after swapping out with the expensive proper volvo part cleared the problem.
 
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This engine has two sending units. One with solid colored wire is for the gauge, one with tracer wire is for the warning panel. Most likely your warning panel in the dash needs to be checked, might be corroded connection giving signal too early. Does pressing Reset button on the dash quiet the alarm?

Yes pressing the reset does shut the audible alarm off. But the alarm will go off and on and I have to keep hitting the reset button. Do you know we're the other sending unit is at? I am only aware of the one on the thermostat housing area... But I'll also check the alarm panel connections as well. Thank you for the tip.ninhadnt checked any of my electrical harnesses yet.
 
You might look at corrosion in the harness connector in your engine bay. I ended up cutting the connectors out and permanently soldering the connection together.... It solved all the guage glitch issues. It could also be a weak ground
that might be a contributing factor. Not sure about this but see if there is any teflon tape on the sender threads, they are not supposed to be coated / insulated with tape. Finally depending on the history of your boat there is a chance the sender is a automotive look alike. I had this similar issue on a oil pressure switch which in my case after swapping out with the expensive proper volvo part cleared the problem.

Also as noted above, I'll have to check my connections since I haven't looked at them yet. My engines are 2003's now with about 820 hrs each on them. I also just replaced the sending unit with a new factory Volvo ($70 unit) with no luck and both the old and new were clean w/no tape. While I didn't think much about my electrical connects, I'll for sure have to take a look since I really haven't investigated them to date.

After I put this post up, I also started thinking maybe its something to do with my fly bridge connects as well. I failed to say I have 2 helms, so I have twice the fun... But these are good tips, thank you as well for the help. I won't get to check though until next weekend...
 
Check the temp alarm sender first. This is the most likely cause and they are not an unknown failure item.
 
Check the temp alarm sender first. This is the most likely cause and they are not an unknown failure item.

Thank you, yeah I did replace that too. At this point I'm thinking connectors and maybe a bad ground. Not much fun to trouble shoot but will give me something to work through over the next couple of weeks. :(

Thanks again for the input.
 
So you replaced the Temp gauge sender and the Temp alarm sender i.e. both senders? If so, get the alarm to go off and try disconnecting the temp alarm sender unit wire at the sender unit. If the alarm stops it is probably the sender itself that is the problem. I just fixed what is more or less the same issue with an oil pressure alarm on a KAD32. Alarm went off even with good oil pressure and it was a faulty alarm sender. Note that many of these alarm sensors are commonly available units at auto parts stores etc so don't rush down to your local Volvo store for another raping if you need one.
 
So you replaced the Temp gauge sender and the Temp alarm sender i.e. both senders? If so, get the alarm to go off and try disconnecting the temp alarm sender unit wire at the sender unit. If the alarm stops it is probably the sender itself that is the problem. I just fixed what is more or less the same issue with an oil pressure alarm on a KAD32. Alarm went off even with good oil pressure and it was a faulty alarm sender. Note that many of these alarm sensors are commonly available units at auto parts stores etc so don't rush down to your local Volvo store for another raping if you need one.

Aliboy,
I'm sorry, I miss understood. I am only aware of one temp sensor or sender on my engines and its right on the thermostat housing area. Do you know were this other would be at? Really appreciate the help on this.
 
Sorry, but I don't know your particular engine model well enough to know where it is located. There is a 97 deg 'Thermo Monitor" (temp alarm sender) shown on the parts list for the 31P, and I have dealt with this issue on other Volvos, so it is worth investigating. Check around the engine for sender units by following the wiring loom. I would expect probably 4 (2 x oil, 2 x temp) to see what you can find. If your engine is like some other models there could be an oil sender in the side of the block, a oil alarm sender near the oil filter somewhere, an temp gauge sender near the thermostat housing, and the 4th one is probably what you are looking for.
 
Well after two full seasons and starting my 3rd season, I have fixed my alarm issue. Turns out it was the temp alarm sending unit. On my 31P's they sit on the exhaust manifold. 5 minute mix and a few cups of antifreeze and I'm done. Thanks for the additional help in troubleshooting this. Huge help. Safe boating to everyone...
 
Well done! Spent today replacing the Trim sender unit on a DPS drive behind a D3 diesel. Now there is a design done by some pox ridden drunk Swede who has never lifted a spanner. Wouldn't be so bad if they could design a trim sender unit that lasted more than 5 minutes of immersion. Donated plenty pf blood to Volvo again today and need to find some way to start getting it back. Wonder if we could convince some of these extremist types that Volvo HQ is really a CIA office in disguise. Could do a power of good for the boating world.
 
Hi I have the same problem on my 31 engine the alarm goes on and the temperature gauge reads 80 c , can some help me were I can find the alarm switch because I only find the sender of the temperature gauge .
Thanks
 
If you read teh 3rd post up above this one it says that they sit on the exhaust manifold. Juts look for wiring in that area.
 
If you read teh 3rd post up above this one it says that they sit on the exhaust manifold. Juts look for wiring in that area.

Hi .thanks for your quick reply... I am really lost as though I ve taken note of this location I can t really manage to find this sensor..I only managed to find 3 sensors;; 1water temp gauge; 1 oil pressure gauge And 1 oil alarm sensor...
 
Just look for wires going to the block. Volvo sensors tend to be 2 wire ones. Sorry I can't tell you the actual location, but there aren't that many wires going to the block
 
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