Termperature Dial Flickers

[avazquez]

The temperature dial on my Perkins 4108 suddenly has begun to flicker. It trembles and when the throtle is applied it inmediately flickers to show a lower temperature. Not that the temperature of the engine is going down. Its just that the dial goes down as throtle is applied and up as it is removed.

It seem like an electrical problem.

Has anyone seen this before???

[never monday]

The temperature will fluctuate a little with changes in engine speed. Engine speed determines cooling raw water flow. More flow = cooler temps for an initial shock the the engine starts building more heat and the temps stabilize.
What your describing sounds like an intermittent connection at the temp sending unit.

[avazquez]

Originally Posted by never monday

The temperature will fluctuate a little with changes in engine speed. Engine speed determines cooling raw water flow. More flow = cooler temps for an initial shock the the engine starts building more heat and the temps stabilize.
What your describing sounds like an intermittent connection at the temp sending unit.

I already checked the connections but I will re-check. On the other hand and maybe related or not, the engine has developed a hard to start symptom. It starts very smoky (white-gray) and rough until the temperature rises and then it works fine. I have already checked the injectors, cleaned exhaust elbow, filters etc. Could it be an air leak in the fuel system?

[Alan Wheeler]

After reading the "hard to start" post, it is quite possible that you have a blown head gasket or worse, a cracked head. Is the engine enclosed freshwater cooled, or raw water cooled. Usually the enclosed systems will blow all the water out if you have a head gasket issue. Raw water cooling will mean you wil never know if you are pressuring the water system.

[donradcliffe]

I also suspect a head gasket issue (or worse)--Did the engine get overheated recently, and/or is the coolant level dropping?

[avazquez]

The temperature has never risen above 190F. Coolant level has remained constant.