Front tow eye rusted threads

[ChapmanF]

Hi,

My NHW11 came with a mint-condition tow eye in its little foam block in the trunk.

But the tapped threads in the front bumper are so rusted that the eye can't even be started into the hole.

If I'm ever in a ditch needing to be pulled out, I'm going to be sitting there saying "but. I. can't. get. this. eye. in. this. hole."

I probably need to buy a tap the right size and run it through the hole, but 'the right size' is the trick. From trying to measure it, I'm guessing it's M21x2, but none of my local hardware or even auto shops has a thread gauge that big to really confirm it. I can mail order a tap but in those sizes they're not cheap, so I'd like to be right.

Has anybody been down this road before? Is there by any chance a PriusChat official circulating "clean up your tow eye hole" tap?

-Chap

[tochatihu]

I put grease and a wine cork in that hole early on, so I don't feel your pain. Can you not just read the thread pitch and diameter off the tow bolt? How about aggressive cleaning, then see if you can get the (oiled) tow bolt started in? Cross-cut the bolt threads with a hacksaw, and file off the first few? It should still grip enough with the deeper threads I guess. Anything to avoid buying that tap (which won't clean the last several threads anyway).

[seesfar]

You might try buying a 3/4" round wire brush and chucking into drill and running for a few minutes in bolt hole. Usually cleans OK.

[jayman]

Originally Posted by seesfar

You might try buying a 3/4" round wire brush and chucking into drill and running for a few minutes in bolt hole. Usually cleans OK.

+1, a Dremmel tool works fine too. Spray a lot of WD-40 onto the threads first, to help break up the loose corrosion. Give a 3-5 sec buzz with the brush, then use the WD-40 to spray out the crud.

This process will have to be repeated a few times, so be patient. If the threads are real bad, a thread chaser or even a tap will be needed.

Once the threads are cleaned, put a heavy dollup of grease in the hole

[Seamus]

Thanks for the tip. I opened mine and sure enough it had a lot of raw metal. I slobbered a lot of grease in there in case I ever need it.

[tochatihu]

Seamus, the 2001-2003 Prius is different because this bolt hole is open to water and road debris. I do not know how well the plastic cover works in the new model.

[Seamus]

Originally Posted by tochatihu

Seamus, the 2001-2003 Prius is different because this bolt hole is open to water and road debris. I do not know how well the plastic cover works in the new model.

Well the "cover" is really just a plug for the hole in the bumper cover. As I mentioned it looks like the threads are not corrosion protected.