Ever seen this?

First, let me preface this by saying that this is not at all typical.
I've just been having a lot of hassles with cars lately. I've had 15
Chrysler minivans over the past dozen years, and most of them have been
delightful to own and maintain.

We have a 1999 Voyager with the 2.4L engine that we've been driving for
the past two years as our family vehicle, and it's been great. It's
always had an oil leak that I finally decided to get rid of. It was
coming from the valve cover, more specifically the #2 spark plug well
which has always been full of oil. I could never get this spark plug
out because I couldn't get the socket to go down on the plug. I figured
there must be a bunch of cooked, gummy oil around it. Well, I finally
decided to change the plug and the valve cover gasket, and solve both
problems this week.

When I got the valve cover off I discovered that I didn't just have a
leak on that spark plug well, there wasn't a gasket there at all! Also,
the spark plug wasn't surrounded by cooked goo, it was stuck in place
with some kind of adhesive because the threads were trashed. The new
plug didn't have any grab at all in the hole.

I thought hard about this problem for a few hours. I figured I could
drill and tap the hole and insert a new thread, which would require
removing the head to avoid getting chips in the cylinder. Or I could
change heads, or there might be some other solution.... I finally
decided to clean it up really well and JB Weld the new plug in place. I
let it set overnight. I was afraid to start the engine today, but I
finally went ahead and did it, and it works great! This has always been
a good running and reliable engine. I just wonder what was wrong with
the former owner, stripping spark plugs out, gluing new ones in,
omitting gaskets, etc. It already has 200,000 miles on it, so I figure
I probably won't have to take that plug out again as long as I own it....

 

He probably didn't have to take it out again as long as he owned it
either. You may have more in common than you thought. ;-)

 

If the JB weld holds up to internal combustion, that's amazing. If not,
they make a helicoil for that. I'd advise using that next time.

 

That requires tapping, but (for the OP) the practice is to put grease on
the tap to capture the metal chips. Probably not 100% effective, but
close enough (remaining chip or two most likely will blow thru to the
exhaust system - if you're willing to epoxy a plug in, you should have
no problem allowing that).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

I don't know why you say that. The only reason I considered it was
because it worked so well the first time. I just don't know how spark
plug holes get stripped out in the first place. It's not as if it's
difficult to get them in and out.

I hadn't ever heard about using grease. That sounds like a good idea,
but probably not 100% like you say. I hope I never run across this
problem again.

 

It's a pretty good van. I might just put another engine in it
eventually. This one's getting pretty easy to turn over by hand.

 

It wasn't a criticism. My point was that a purist (anal-retentive)
would not epoxy a spark plug to the head, nor would a purist
(anal-retentive) risk getting any chips into the combustion chamber. My
meaning was that you don't appear to be averse to doing either and
therefore could get the job done either way.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Thanks for the clarification. I'll certainly keep that grease idea in
mind in case I ever need it, which I hope I don't.

I think the greatest motivation in this whole escapade was to get it
finished because I've been spending way too much time working on cars
lately. The water pump on this van had been making noise, so I decided
to change the pump and belt. I've always liked the relatively generous
space around this engine, but I was disappointed to discover that
everything has something else bolted on top of it. Then I broke the
harmonic balancer trying to get it off. Boy was it stuck on there!
Seems like a silly design to me. Then I discovered that the last person
to work on this thing didn't even make sure all of the gaskets were in
place. By the time I found the glued plug I had just about had enough.
For comparison, I changed the pump, belt and valve cover gasket on a
1993 civic last week in about an hour. That's a really well-designed
car comparatively, in case you ever get a chance to buy one. Anyway,
the van engine seems at least as good as it was last week. I'll let you
know if the plug ever blows out of the hole. We put around 40,000 miles
on the other one, and I don't know how long it had been in there before
we bought it.

 

Because tapping a head and letting the (few) chips that fall into the
cylinder blow out the tailpipe is sane, normal, and common. JB-welding a
spark plug in place is stark-raving looney.

 

You have a point. I guess I should have mentioned it before I went
ahead with the job and you guys could have straightened me out. I was
thinking that chips in the cylinder would pose a greater risk than you
guys are telling me now.

I am glad that I know the grease trick now. I'll keep that in mind. I
really am the kind of guy who likes to do things right when possible. I
didn't want to use JB Weld, but it seemed like a good idea at the time.
I've put a hundred miles or so on the van since I got it all together
and it works as well as it ever did, so no harm done this time.