Firewall grommet replacement?

[Nodents2017]

Is there any decent way to replace this grommet besides buying a whole new engine harness? This is not my picture but the grommet I am talking about is circled in red. Previous owner split it open pretty good running some wires through it and if possible I would like to replace it. Thought about buying a used harness from a salvage yard or hoping it is the same grommet used on previous generations and I could find one at a junk yard. Anyone replace this before?

4Runner grommet - Album on Imgur

 

[jp.vegas]

That's a tough one to replace. Looks to me like it requires splitting the harness, whatever liquid tube that is etc. I've dreaded thinking about that every time I run something through it. Did it on my 4th gen and now my 5th too. It's a knuckle biter each time lol.

To be honest, you're probably better off leaving it as is unless you for sure have water leaking through it.

Good luck!

 

[Bmnorm2]

That would be a real pain to replace.

RTV? Not pretty, but functional and can be “removed” in future if needed.

 

[Brandonium]

I would prefer drilling a new passthrough with grommet before ever hacking on something like that. Some previous owners are just amazing people. lol

 

[Nodents2017]

It didn’t seem too bad to replace. The harness goes inside and down to a junction box on the passenger footwell. There’s just two connectors that need to be disconnected and could probably be pulled through carefully or might need to de-pin them. The washer fluid line has a disconnect that will allow it to be removed easily. Seems like the grommet extends over the wire harness in the engine bay and is just electrical taped.

Would be nice if I could order just the grommet from Toyota but doubt that’s possible. There’s a 4th Gen 4runner at a local U Pull and Pay near me and I believe the grommet is the same from what I’ve seen. Going to take a trip down there this afternoon, hopefully the harness is in tact and I can practice on that one. I’ll update the thread with what I end up doing since I’m sure others would be interested.

 

[Captain Spalding]

Maybe you could cut the new grommet in half, install it, and then seal the seam. Just a thought.

 

[flyrv9]

It seems like you should be able to buy just the grommet; although replacing it might be a pain. You can do a nice job with RTV by smoothing it out after application. The way to not make a mess is to put some liquid soap on your finger and smooth out the RTV before it sets up.

 

[Humble Leader]

RTV black automotive high temp on both sides of the grommet will work and last. it's probably not worth the hassle of trying to buy a new wiring harness or a new grommet and splitting it in half. I mean you could do that, but the black RTV will work and won't be noticeable if you are careful and do a good job

 

[Nodents2017]

Well, I was able to find the grommet at the local u pull and pay. Grabbed it off of a 2006 and seems to match exactly.

Success! - Album on Imgur

Unfortunately I noticed when removing the harness from the grommet that there seems to be some rubber/resin potting material they used to seal the harness as it goes through the grommet. I was able to pull back the grommet carefully and get the harness to come out but I’m not sure I’d like to take that risk with the grommet currently on my 4Runner.

I’ll likely go the RTV route and as long as that holds up I’ll be fine. Probably just going to keep this spare grommet around as a last resort. It was $1.70 which is about %2000 cheaper than a new harness.

 

[rageandlove]

I would prefer drilling a new passthrough with grommet before ever hacking on something like that. Some previous owners are just amazing people. lol

Do a search on "running wires through firewall" - the most common reply (on dozens and dozens of threads) is "poke a hole/cut a slit in the grommet" ...

There are non-destructive approaches that don't even involve drilling. I've documented 2 in threads somewhere in here ...

 

[jehardyiii]

Trick for getting firewall grommet around plastic?

I stupidly removed the engine wiring harness rubber grommet from the plastic piece where it runs through the firewall when I was troubleshooting some electrical issues. It's intact, but I'm having a heck of a time getting it back over the plastic piece. It's like getting a tire on a rim (they're both circular) and it's tough to keep one side in place while you stretch it over the other side.

Does anyone have a trick to get this done? Or is it one of those "just keep trying until you get it" kind of things? Is it so nearly impossible that I'm unlikely to get it done? I'm nearly to the point of just splitting it in half and doing the RTV treatment.

Thanks!