Strange spark plug problem. I can't get #3 threaded in properly.

[Pat Mercadante]

Putting in the same thing I took out, but 8 new ones, Autolite 85.
I'm in a tight spot, behind the oil dipstick, and 2 hose connectors for the Borgeson power steering.
I got the old one out, but I've tried 4 times at least to thread the new one in and I only get maybe 2 turns.
Old plug shows NO signs of crossthreading. I'm frustrated.
HELP!

Put a piece of vacuum hose over the ceramic section and then try to install it

 

[Canned Heat]

Must be a budget control setting on my phone. Can’t spend or pull anything up over $10.


View attachment 1361062

I did not read the whole thread. I have a thread chaser similar to the one above that I have used for over 20 years. To catch any debris I put the tool on a powerfull magnet over night and also cover the tool with the thickest grease I can find. You can also bring the piston to top dead center to keep the debris close to the plug hole and use a magnet and scope to see if you have gotten all the debris. If you have to pull the header to one side or take it out, DO IT. You have to be comfortable getting the tool in the hole straight. It may seem like a lot of work but it is easier and cheaper then pulling the head if you screw it up. Never put new plugs in dry, especially with aluminum heads. A little grease on the thread is a good idea. That new tool looks good. I might get one. Good luck.

 

[Canned Heat]

I was thinking I may need something "like that" and that tool is exactly "the thing".
Of course the spark plug hole is in one of the hardest places to get to.
THAT tool may be exactly what I need.
Thanks.

and that is probably why it got damaged in the first place.

 

[mopar 3 B]

I did not read the whole thread. I have a thread chaser similar to the one above that I have used for over 20 years. To catch any debris I put the tool on a powerfull magnet over night and also cover the tool with the thickest grease I can find. You can also bring the piston to top dead center to keep the debris close to the plug hole and use a magnet and scope to see if you have gotten all the debris. If you have to pull the header to one side or take it out, DO IT. You have to be comfortable getting the tool in the hole straight. It may seem like a lot of work but it is easier and cheaper then pulling the head if you screw it up. Never put new plugs in dry, especially with aluminum heads. A little grease on the thread is a good idea. That new tool looks good. I might get one. Good luck.

Heat and grease is about like adding glue. Years ago we greased head gaskets to seal them. Next time the head came off the grease was baked hard. Not sure I would want that in a spark plug hole or in the cylinder.

 

[biomedtechguy]

The tool came in today.
If I get to it this weekend, I'll post results.
Thanks

 

[YY1]

 

[biomedtechguy]

Well....
The tool came in with the larger diameter inside "fluted" rod end pulled into the split threaded part, and it doesn't really get smaller in diameter when the inside rod is lengthened, moving the fluted part out. There's zero resistance to pulling the fluted part into the threaded end, but I thought it should have lots of tension as it spreads the threads??
I thought it was going to be small enough to slip past the threads, then the inside rod retracted, spreading the split threaded part out to the diameter needed, then removed, cleaning the threads on the way out. I'm sure that's how it's supposed to work.
So I'm going to try wrapping a wire or something around it and twisting it to compress the threaded part down to the smallest diameter, put a plastic zip tie around it to hold it, see if that allows it to slip into the hole, then clip the zip tie, pull the fluted section into it, then turn it ccw to clean the threads.
Am I missing something??

EDIT: This is how it's supposed to be:

So I'm going to have to get the splits closed, and have them stay that way until I pull the fluted part into the tool.
Like this:

 

[Charged440]

I imagine you don't want to wait any longer but I might send that back, it clearly wasn't made right and who's to say what else is off about it.

 

[biomedtechguy]

I imagine you don't want to wait any longer but I might send that back, it clearly wasn't made right and who's to say what else is off about it.

I will just find a way to bring the 4 sections together. I may just bend them in a bit w/thin needle nose pliers. I totally get the procedure to do the job, and the threads on the tool all line up, so I'm ok w/that.
I don't think it's a defect, maybe just what happens when tools are cheaply made.

 

[Fran Blacker]

Small hose clamp at the top of threads. I would only do the threads at the start of the hole. If plug threads in smoothly your done. If there's a problem where you didn't chase the threads do it again deeper.

 

[biomedtechguy]

Small hose clamp at the top of threads

That may be workable, but I intend on passing the collapsed tool past the threads, then expanding it and reversing it out. I'd have to be able to get to the hose clamp to loosen it, and I don't know if that's possible.
I took another look at the area, and it's going to be difficult to work in. Very "busy" by #3 and no fender opening to help.

 

[biomedtechguy]

I would only do the threads at the start of the hole.

With grease, that may work. I wouldn't have to collapse it if collapsing it proves difficult.
BUT
Collapsing it and only backing out through the damged/dirty threads makes it unlikely any debris could get into the cylinder.
I'd use grease regardless.

 

[Photon440]

That may be workable, but I intend on passing the collapsed tool past the threads, then expanding it and reversing it out. I'd have to be able to get to the hose clamp to loosen it, and I don't know if that's possible.
I took another look at the area, and it's going to be difficult to work in. Very "busy" by #3 and no fender opening to help.

Use the clamp, but instead of clamping directly on the fingers, put a match stick on each one before clamping down. Then you can install the tool and tighten up to expand without removing the clamp, the matches will just crush instead.

 

[biomedtechguy]

Use the clamp, but instead of clamping directly on the fingers, put a match stick on each one before clamping down. Then you can install the tool and tighten up to expand without removing the clamp, the matches will just crush instead.

I don't understand.

 

[RJRENTON]

With grease, that may work. I wouldn't have to collapse it if collapsing it proves difficult.
BUT
Collapsing it and only backing out through the damged/dirty threads makes it unlikely any debris could get into the cylinder.
I'd use grease regardless.

I FEEL FOR YOUR PAIN AND FRUSTRATION.....since you appear to have 3/8" reach plugs (Autolite AP85),, do you have space from the end of the chasing tool to the top of the piston, once you finally get it into position? Where is the piston relative to TDC? You may have to resort to a heli-coil insert, using their tap and insert tool, bear in mind this method MAY effect the cooling of the spark plug (it will likely run slightly hotter...maybe not....TBD). But, face the realization that you may have to pull the head and seek professional assistance to affect a fix.
Years ago, my commuter ride was a Ford Pinto 2000cc 4 speed with 18mm taper seat spark plugs. I had been using Champion F9Y, because of engine mods.....more cam, etc. Changing plugs, the first 3 came out fine, #4, the last one, was tight. I had used anti-seize on the threads ~ 11,000 mikes previously. Using the tried and true Army method, brute force and blind ignorance, and using a deep well spark plug socket, a short extension and a 2 foot long ratcheting breaker bar, i applied a significant amount of torque.....the plug sheared off directly below the hex....the ceramic and the top half were in the socket....the threaded part was stuck in the head. Soaking overnite with PB BLASTER, I decided to try an EASY-OUT left hand thread tool..... if that did not work, the alternative was to pull the head. But the Army method prevailed......after much grunting....the threaded end of the plug came out.....and the head threads were un-damaged....I threaded a chasing tool in the hole, lightly coated with grease, to capture any chips, just to make sure......spun the engine over with the starter with all plugs out......installed a new set of Motorcraft BTF-3 plugs with threads coated with nickel based anti-seize compound.....and went down the road.....without any further difficulties.......I feel your pain......just talking out loud......
BOB RENTON

 

[4406bbl]

X2 on the nickle based antisieze, I do not like how some of the new cheap aluminum based stuff looks when you take things apart, especially exhaust manifolds.

 

[threewood]

Any updates?

 

[biomedtechguy]

Any updates?

Not yet. I've been very busy with work. I am planning on getting back to the spark plugs this weekend for sure!

 

[1 Wild R/T]

You just can't catch a break...

 

[biomedtechguy]

You just can't catch a break...

I'll be happy if it all works out this weekend. I'll definitely post details.