Once again I beg your indulgence!

[JAT]

Here's what I have...and it makes me really wonder.

On one of my engines...a Perkins 6.354 circa 1979.... I replaced the oil pressure sending unit. That was a while back....but what I have found, is that it appears that the wire from the sending unit has gotten very hot and looks a bit cracked and charred.... Not good I know.

Actually both of my sending units were replaced at the same time, and I have not had the same happen with the other engine.

Now....with the engine running, oil pressure gauge on, and alternator on (alternators on both engines triggered by oil pressure)...I can wrap my hand around the wire that appears burnt....and there is absolutely no heat from the wire.

Whats really a bummer....is that I cannot remember what the wire looked like when I put the new oil pressure sending unit on the engine.

Any ideas??

 

[koliver]

Hit the wire now with a little spray paint, then you will know if there are any changes due to heat.

 

[O C Diver]

Engine gauges draw and handle very little power. If you drew enough amps through the wire to cook it, the gauge would have died first. Think I would look for a heat source that the wire may have been against, like an exhaust manifold. Also, if the wiring harness is easy to open, check that wire a few feet away from the engine. If you cook a wire with amps, it generally cooks the whole length of the wire. With a heat source, the wire only gets cooked near the heat.

Ted

 

[JAT]

Thank you both...I will do both suggestions!!

 

[Castrol]

Burnt wire

Hi, both are good answers but you may have had a slight leak to earth at one time causing the wire to appear burnt, I think replacing the wire would be a good idea in case it happens again only next time may ignite something else especially if its near fuel. Good luck

 

[rwidman]

Engine gauges draw and handle very little power. If you drew enough amps through the wire to cook it, the gauge would have died first. Think I would look for a heat source that the wire may have been against, like an exhaust manifold. Also, if the wiring harness is easy to open, check that wire a few feet away from the engine. If you cook a wire with amps, it generally cooks the whole length of the wire. With a heat source, the wire only gets cooked near the heat.

Ted

That is a very good post.