Lost a spark plug
 

So my car has been having issues anyway and I recently did a compression test to find out that I had no compression on one cylinder. I don't know if it was me putting everything back together poorly or something else.

My car has been sputtering and dying lately but I thought it was from a gas-additive I put in the tank trying to free up the valve on the bad cylinder. The dying did not start till right after I added the additive. I bought the additive at Auto Zone when I took the compression test kit back so I probably should have considered that it might be something else but nothing looked wrong. I have to add oil frequently due to a leaky oil pan seal (on my to do list with the engine rebuild). I am sure that I would have noticed a spark plug hanging when adding oil, it was the first thing I saw when I popped the hood.

So what causes a spark plug to back itself all the way out? The hole was empty and my spark plug wire was hanging there not attached to a plug. This is a different cylinder than the one that had no compression.

It may have blown the threads clean out of the head. I've seen it happen before, usually due to overtightening.

Hmmm... That sounds like it will be fun to fix. Maybe I should just ditch this engine. Might be cheaper to just find a 1.0 to put in it and get better mpgs anyway. Going to start looking for engines.

The fix involves a $30 Heli-coil kit and about 20 mins of your time. You just tap the head with the included tool, thread a new thread insert in with silicon sealant on it, and then thread the spark plug into the sleeve and all's well again.

That's not necessarily what happened, though. It was just a suggestion. You'll have to check for yourself to see if the threads are damaged.

Frankly, it could have just been not tightened properly, and backed out from vibration.

If you're going to replace your engine w/ a G10, you have to replace the trans/axles, as well. The G13's transmission is mounted/designed slightly differently because of the engine length.

I am confused, how is this not the same as the people that have metro's with the G10 swapping in a tranny from my car? I thought I would be a step ahead since I already have the taller gearing.

It is dark now and the car is sitting on the side of the road a few miles from here so I can not look and see for sure if there are any threads left. I see it taking far, far longer than 20 mins though lol. It took me that long just to get the compression test kit screwed in to each spot. Very little room to work with around the spark plugs.

Hopefully when I go to tow it back here tomorrow I will find that the threads are indeed still there.

IF you mount the G10 to a G13's transmission, the engine will sit too far to one side, is all. (That I'm aware of)

There are people here that know more about that part than I do.

I see. Gonna have to do some research then. There is a 4 door lsi for sale on craigslist for 350. I would then have the springs to lower it and a 3 cyl engine if I can do it. Thanks again.

You don't have to closely examine the threads - just try to screw in a spark plug and see if it tightens.

The helicoil is a good quick fix. Be careful in the future to tighten, but not over tighten anything, especially when screwing into aluminum.

The 3 cyl engine will fit in the 4-cyl car without messing with the transmission/axles, but it'll sit further to the driver's side than it did in the 3-cyl car, so you may have to mod the motor mounts.

It's going the other way that is more of a problem (4 cyl engine into 3 cyl car).

...aircraft radial engines were notorious for "blowing" spark plugs.

...the R-3350 turbo-compound engines with PRT's on our Lockheed EC-121 "Warning Star" aircraft would typically loose either a "plug" or a "jug" about once or twice a year...of course, that's after running continuously for 16-20 hours at a time during each flight.

I am guessing it was probably not tightened enough, My spark plug socket was not actually deep enough, I ended up with a half-assed hand tightening since I could only get finger tips on it. We shall see, I am waiting on someone to tow it back here for me so I can look at it.

@metro - Thank you for the input. I will be doing more research about how I plan to tackle this.

@teleman - I am glad they did not put those engines on the P-3 Orions I used to fly on in the Navy lol.

...yeah, but did you stay airborne for almost 20 hours? I know the P-3's routinely shut-down two of the four engines while on patrol...we often did, too, but not intentionally(ha,ha)!

There are more sophisticated variants that in-flight refuel and stay up for over 24 hours. Ours were typically 16-18 tops. More often than not our engines shut down for unplanned reasons, good thing there were 4, we landed more times than I would like to remember with more than 1 inoperable.

Well I think I got lucky this time. The plug just backed itself out. Threads were still there. My chilton manual did not specify a torque for my engine, only for the 98-00 which I did not notice when I first replaced the plugs. 1 of them was still in ok shape but I think it was because the wire was not properly seated on it. The cylinder that I have no compression on had a lot of carbon build up for only being in there for 2-3 weeks. The third one that was still in the motor was deformed and burnt up.

All new platinum plugs torqued properly. New wired, cap, and button. Car is running as bad as it did the day I got it again :).

Now I need to find some valves so I can make the trip up to see metroshultz and rebuild this thing. 3tech does not seem able to get them for me since I have the "unpopular" engine for this line of cars and not the 1.0L or the GT version.

...check the factory specification books, as often parts (like valves) are interchangeable with different engines.

...the guys at a reputable "junkyard" might know what parts "fit" into other engines.

Good call. I was trying to get some stainless ones from 3tech. I very well might have to go with something from another engine just to be able to find some.

Go to Rockauto.com, check if they have a listing for your part. If they do, click the part number listed, and it will give you interchange information.

Great site. That place is 1/4 the price as the only other place I have found them so far.

Rockauto is a good place. I've bought from them several times before.

While the 3-cyl will fit, the two-piece axle from the 4-cyl has no place to bolt to on the 3-cyl block. You could weld the differential and only use one axle for some friction reduction. :)

If you decide to buy your parts at Rock Auto, do a web search for Rock Auto promotional codes and you'll probably be able to find one that works and will save you at least 5%.

Remove one axle, leave the diff unwelded, and freeze the unused side of the diff gears. That'll give a 2:1 reduction at the axle that still drives.

An old axle trans-side stub with a plate welded to it could work perfectly to stop the other side of the diff from spinning, too.