1000hr opti over heat alarm??

[Tris]

225opti done 1000 hours. Just serviced. All water pump inc housing wear plate etc good. Impeller new. poppet valve replaced last year.
At Tickover the smart craft gauge reads 0.6-0.8 bar block pressure and the temp rises until over heat alarm Sounds. Lift RPM very slightly and the temp falls rapidly down to 36. Let it idle again and the temp rises up. The tale tale is good but not as strong as I would expect. Stat is good and water ways you can get to are very clear with no signs of crystallised salt.
Any other ideas.

[martini]

Stick your hand under the tell tale and feel the temp when at idle and compare to when the gauge is reading low. Might be a sensor fault.

Also don't assume because it's got a new pump that it's been fitted correctly. Impeller could be the wrong way round for example. No biggie to drop the leg again and have a look.

Sent from my portable speaking device using Rib.net

[Tris]

Originally Posted by martini

Stick your hand under the tell tale and feel the temp when at idle and compare to when the gauge is reading low. Might be a sensor fault.

Also don't assume because it's got a new pump that it's been fitted correctly. Impeller could be the wrong way round for example. No biggie to drop the leg again and have a look.

Sent from my portable speaking device using Rib.net

Checked and double checked. Impeller can only go one way. One side in its casting has a slot for key. The other is blanked. I am leaning towards sender to be honest. May take a look at replacing in the next port of call.

[uncle al]

if you look on the port side of the adapterplate you will see a water hose going onto a nylon connection , remove connection and clean the filter,then if required check thermostates

[Tris]

Originally Posted by uncle al

if you look on the port side of the adapterplate you will see a water hose going onto a nylon connection , remove connection and clean the filter,then if required check thermostates

Stats checked today. All clean and open close free. Will check filter. Thanks.

[Turbodiesel]

Have they done the poppet valve correctly? Get on the phone to the people who have just serviced it!!!