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Old Volvo penta trapezoid engine harness a fire hazard?

Yes sir the engine harness. Michigan motors told me to get rid of that connector completely and splice the new harness for the new engine together with heat shrink marine grade butt connectors. I told the shop this and they just plugged it back in. They said that old style plug can't handle much current and causes a fire frequently. I haven't seen anything on the internet about it though. I think this is mainly because people tap into the ignition for 12v power and run too much current through the engine harness instead of using a fuse block connected directly to the battery.
 
If you are talking about the old, white, plastic, multi pin harness connectors........ (the ones that have a two-part black plastic covers) .... yes, any Volvo Penta AQ series mechanic should know that these have been problematic as they age.

The smaller circuits; temperature, oil pressure, Ignition etc, are usually ok.

They do develop problems with regard to the starter “S” circuit, the positive running to the helm, and the negative running to the helm.

All that said, the male and female wire terminal connectors can be removed from the white connector housing, and can be replaced with new terminals, and then pushed back into the harness connector.

I would suggest NOT using butt connectors with the pre-applied shrink tube!
Some crimping tools will cut through the shrink tube, and when heat is applied the shrink tubing will break and open up in that area.




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Here is the plug on the engine side. The other half is connected to the harness on the boat which goes up to the console I believe. I don't have a pic yet of them put together on the new engine. That harness uses both the trapezoid plug going to a flat plug.
 
Yes.... that is the connector that I was referring to.

I couldn’t for the life of me figure out what you were calling “trapezoid“ engine harness!
 
Where do you find those plastic connectors?
I mentioned that you could replace the wire terminals.... not the plastic connector housing.... although I'm sure that you could find both parts if you looked hard enough.

Are you saying just replace them periodically and it will be fine?

Most of these connectors are mounted on the inside of the transom, so they tend to corrode.
If you cut all of the wires back evenly, strip them the correct length, and install new wire terminals....... continuity will be regained.

However, I still do not like seeing the larger current of the helm Positive and Negative being carried by these small spade style terminals.

These are why have used over the years. I forget the brand name, but I did find these in a Wurth brand.
The difference between these and a typical male/female spade connector, is no insulator, the crimp for the bare wire, the crimp for the wire jacket and the locking tang.

Volvo Penta harness   push spade connector fittings.jpg



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By the way, how did you come up with the word “trapezoid” to describe this?
No offense..... I’m just curious as I’ve lost sleep over it for the last several nights. :D
 
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