Compression test stuck in sparkplug tube
 

I tried doing a compression test on my 4 cyl engine after doing a valve adjustment and its been a disaster. I rented a tester from oreilly and the cheap gauge blew its valve. I left it threaded in over night (my first big mistake) after this happened. Since I had run the engine before doing this test, when I threaded the tester in the metal had expanded, once I let it sit the metal contracted and grabbed the adapter even more.

In the morning I removed the tester from the engine, but all it did was unscrew the hose from the metal adapter, so the adapter was left in the engine. Here is where I made my largest mistake, after trying a few sockets I thought that since it was already broken I would just read loctite the hose onto the adapter before removing it as a whole.

Instead what happened is that the red loctite did its thing, and predictably rather than the adapter and the hose threading out as one, the hose just broke free of its metal collar and spun around independently of everything else. I did not red loctite the compression tester to my engine to be clear.

So now I have a hose that blocks access to the base of the adapter, and I cant use the hose to spin the adapter out. What should I do?

You could try cutting the rest of the broken hose off of the adapter end and try to get a socket on it.

Its far enough down that its difficult to reach, so I was thinking of burning it off. I don't know if removing the hose will make it easier or harder.

So before you put the hose back on you tried to loosen the adapter with a socket and couldn’t? Because the socket didn’t fit or because it was too tight? I know my spark plug socket is a tight fit in those tubes

What material is the adapter? If it’s brass that would be best for a chance of getting it out I think

Before I put the hose on I tried using the spark plug socket. It was too large, I then tried a 14mm and it was too small.

Being very disorganized I decided it would be easier to use the hose to spin the adapter out instead of looking for another socket. The hose threads onto the inside of the adapter, and I thought that if the hose couldn't unthread from the adapter then the adapter would have to come loose.

The adapter is brass

I’m not sure if it’s possible to remove the tube itself but I know some Toyota tubes are removable. Maybe look into removing the tube and then getting at it that way.

If you think you can snap the metal collar and hose off the adapter easily I’d go that route. I use a 5/8 socket on the plugs so the adapter is probably 15mm

Worst case scenario I’d find a steel rod that I could grind a flat blade onto the end then hammer it straight down into the middle of the hose/adapter combo and spin the whole thing out with vise grips

To remove the spark plug tube you have to remove the head. Its not easy.

I lucked out and found a pipe that fit around the edge of the adapter and spun it out. So I don't have to worry about taking it to a mechanic on 3 cylinders.

What a wild ride.

Did your engine need a valve adjustment or you just did it preventatively? (Discouraged for 5VZFE)

Holy cow dude, testers tend to be hardened metal, and our intended to literally be thread it in while attach the hose only finger tight.

Are you confident you used the correct adapter? Red Loctite has a tremendous a prevail force depending on the quantity and which brand….. many times it’s required to liquify, essentially, the red Loctite. Red was probably a super poor choice here. Blue is the one to use there.

I still think you either cross threaded the adapter, or had the wrong adapter to start with. They usually fall together very gently.

Worst case scenario you’ll have to pull the head here. Good news is this is going to be a character building experience for you. It ain’t all bad, we’ve all screwed up tremendously before and you learn the most from the screw ups. I had to tear apart of diesel engine one time after I sucked a paper towel in the intake and blocked the valve. That was in a Tele handler loader, about a good 10 hour job just to get to the engine……. You’ll get about a temporary insanity, collect your words, and then fix your eff up.

Good!

Oh man, I just recently did a compression test and I was afraid this might happen to me. Lucky enough it went smoothly. Make sure next time to really tighten up between the adapter and threaded hose.

If I'm in this situation, remove the hose and insert either 15 or 16mm socket to get the adapter out.

Good luck man!

Oh gosh, I can totally to relate to these sorts of things! On my old 91, every stinkin time I'd go to fix something on it, something else would break or go terribly, terribly wrong like your experience. Once time I had the valve covers off and I dropped a bolt INTO THE HEAD near the crank. Talk about stressful. Not to mention all the trips to the local pick-n-pull because everything was brittle and would break if I happened to just look at it.

I am very glad you got it out and can sleep well.

glad you got it out. I had a scare like this a few months ago when I bought my "newest" rig. doing a full tune up etc....and I "rented" a compression tester from O rielleys cause mine is ...someplace. on one of my last tests the hose just kept spinning and not pulling out the plug adapter. I got pissed and afraid of "now what". pushing down hard it came out. Thanked all the Gods I could think of at the time. think im gonna look into a quality compression tester to buy......ideas ?
btw....i used to have another great tester and leak down tester...guess for some reason they did not make the move from oregon to alaska 4 years ago...prob in my oregon sons tool box.
cheap stuff is cheap for a reason....and when it fails...the follow up isn't cheap anymore.

OTC makes a compression tester, I would go with them since their other stuff has been high quality. Snapon sells a tester, but its overkill for home mechanics and you pay for it.

Don't go with Performance Tool tester, none of the measuring instruments I've bought from them (a multi-meter and a normal battery tester) have felt like something I would trust. The multimeter was clearly a common rebrand of an accurate yet basic cheap multimeter, and the battery tester was poorly assembled.

The tester I used that got me in the mess was an Ever Tough brand. Eaton uses Ever Tough name for some parts, but it seems like the brand that made the crappy compression tester is no way related to Eaton.

For those wondering the diameter of the pipe I used was 12-13 mm outer diameter, and maybe 1 mm thick. I don't have tools to make a more precise measurement than that

OTC makes Snap On and Matco's compression testers and leak down testers. I'd recommend OTC over anything else out there.