MC4 O-ring size?
- Thread starter Joules22
- Start date
Bluedog225
Texas
- Joined
- Nov 18, 2019
- Messages
- 3,120
I don’t think there are standards. That’s part of the problem with mixing diff manufacturer‘s mc4s. Harbor freight has a big box of orings for cheap.
Yeah, I have their Viton set. No go. Well, let's put it this way, I found one that's an OK fit, but it doesn't want to connect to its mate. Maybe some silicone paste...
Bluedog225
Texas
- Joined
- Nov 18, 2019
- Messages
- 3,120
If you hadn’t seen this, worth a look. Esp the last post. I’m seriously thinking of cutting off all the MC4 and butt splicing.
diysolarforum.com
MC4 alternatives
All the extra parts and tools including MC-3 dies are a waste of your money. I can pretty much guarantee you will never use the MC-3 dies. Even if you did you would need a special tool $$ to insert the contacts into the rubber housing. A personal preference of mine is the blue MC-4 crimper...
diysolarforum.com
Silicone paste did the trick. I see now I could have shoved it together without lube, but I'm from the don't force it school. For future reference, I have the HF 180pc metric Viton o-ring kit (67525). The one that worked for me was A010, 6.07x1.78. Almost as good as 5.32 ?
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If you hadn’t seen this, worth a look. Esp the last post. I’m seriously thinking of cutting off all the MC4 and butt splicing.
MC4 alternatives
All the extra parts and tools including MC-3 dies are a waste of your money. I can pretty much guarantee you will never use the MC-3 dies. Even if you did you would need a special tool $$ to insert the contacts into the rubber housing. A personal preference of mine is the blue MC-4 crimper...
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Don't fear the MC4. There are very few posts here on the forum of MC4 failures. Mine have been on the roof of my RV for two years without any issues. I checked them last month and they look about the same as the day I installed them.
An incorrectly crimped/assembled MC4 is a different matter.
