| Author |
Message |
    
aknetman
Member
Username: aknetman
Post Number: 10
Registered: 05-2008
| | Posted on Tuesday, July 16, 2013 - 10:15 pm: | 
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Does anyone know what the normal/max cylinder head temp is on these engines? The raw water out of the manifold is about 115-120F and the highest temp I can get with the temp gun is 150 at the cigarette holder. I can hold my palm on the head for about 1.5 seconds. The temp gauge I have is "VDO" 40-120 Celsius, and is reading 110-120 (must be a mis-match to this engine). |
nobby
Member
Username: nobby
Post Number: 28
Registered: 12-2005
| | Posted on Wednesday, July 17, 2013 - 12:17 am: |
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Sabb has it at 50-60 DEG C, 120-140 DEG F, which is standard for a raw water cooled engine. Higher temps cause the salt to precipitate out of the water. Two different ways to achieve this on the Sabb depending on configuration. Either without a thermostat one adjusts the sea cock at full load or with a thermostat whose opening temp is 55 DEG C, 130 DEG F. Your a little cold but not to far off. Many caveats to what temp to run a diesel at but for raw water cooling I'd rather be a little cold than too hot and get into the salt precipitation issues.
Cheers
Nobby |
jimdereynier
Senior Member
Username: jimdereynier
Post Number: 82
Registered: 08-2007
| | Posted on Wednesday, July 17, 2013 - 11:53 am: |
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NOBBY has got it correct. On a 2H, The OEM thermostat is rated for 55-65C. ( 150F). Under load in forward, mine runs 180-200F after 1 hour, Reverse under load 180F. I run only antifreeze/water in a closed system. I cleaned the heat exchanger maybe 3 years ago and probably should do it again. |
aknetman
Member
Username: aknetman
Post Number: 11
Registered: 05-2008
| | Posted on Thursday, July 18, 2013 - 10:59 pm: |
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Thanks for the replies. I will look for a new gauge since this one is reading incorrectly. Gauge is ranged 40-120c and engine is running at 65c but gauge reads 120c... Maybe the temp sensor is bad. I cannot run around with the temp gauge pegged. If the engine is running too warm, I expect to have problems quite soon as the salt builds up. If anyone has current part numbers for the gauge and sensor that would be greatly appreciated. |
nobby
Member
Username: nobby
Post Number: 30
Registered: 12-2005
| | Posted on Friday, July 19, 2013 - 05:42 am: |
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Full scale reading on a Temp Gauge usually means that the sending wire is grounded out somehow. So I would usually suggest checking wiring for a possible grounding of the sender wire or just replacing the sender. However this can start to get complicated because the manual shows that Sabb used either a VDO gauge or a Smiths Gauge, the issue being that Smiths sometimes used a voltage stabiliser for power supply as they use a constant 10V supply. In this case changing the voltage input will also change the gauge reading and IIRC higher supply voltage is a higher gauge reading. Also I am not sure if they used the same resistance range for the sender, temperature is usually a little more tricky in that manufacturers tend to have different maps for resistance vs temp. Sourcing Smiths stuff can be a chore and not cheap.
So firstly what make gauge is in the panel, it could also be a replacement unit and non Sabb supplied?
Cheers
Nobby |
aknetman
Member
Username: aknetman
Post Number: 12
Registered: 05-2008
| | Posted on Friday, July 19, 2013 - 10:20 pm: |
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It doesn't peg 120C immediately, only when the engine warms up does it creep up that high. So I think that the gauge is ready roughly double. I figure that I have the Smith-compatible sender, I will just replace it with a standard one and keep the gauge I already have. The gauge is not original, I replaced it when I overhauled everything. |
nobby
Advanced Member
Username: nobby
Post Number: 31
Registered: 12-2005
| | Posted on Friday, July 19, 2013 - 10:59 pm: |
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Well in that case then yes install the same make sender as the new gauge you installed.
Cheers
Nobby |
