240 compression problem!

[my89240sx]

From looking at previous posts, this appears to be a common problem. My 89 240 was running fine, then one day decided it wouldnt start unless you held it to the floor and cranked it for 1-minutes straight, after that it would run fine until you shut it off. I went through the general checks, spark, timing, fuel, everything was fine. I checked compression and found 100 in #1, and 20 in 2, 3 and 4. I cranked it over with the compression gauge hooked up and they never jumped, so I ruled out valve sticking. I dropped in a tablespoon of oil and they jumped up. This leads me to think its the rings, but I've always kept the oil changed on it and have never had problems with power. As a side not, their is a 1/2 inch or so tube that runs from the breather box to a box mounted to the driver finder well and it has a hole in it. Anybody know what this is or knows if it could effect compression? Any thoughts are appreciated.

Adam

[onosqv]

Well for the 1/2" tube, I believe you are describing the iacv or whatnot valve. That doesn't have much to do w/ starting the car, but will affect idling.

Damn man, your compression sucks, haha. Bad head gasket??

cranking your car for more than 15 seconds is not a good idea - 1 minute is very bad.

Well you can perform a leak down test (has some troubleshooting tips also) that was made by s13guy:

zerothread?id=100766

[my89240sx]

thanks for the pleasant thoughts. Yes, I knew I would probably burn the ole starter out, but I was in one of those great frustrated moods after working on it for 6 hours! I have also realized that I checked the compression with the fuel pump still active, which I have read will lower the results.

[my89240sx]

and what the possibility that the damn headgasket blew along 3 cylinders?

[onosqv]

well it is an 89 .

I'm sure one of the other guys will chime in w/ other possible results. The only reason why I think it's head gasket is that it's the most common one when people get really low compression/no compression.

And forgot to mention: WELCOME TO THE FORUMS!

Just peruse a little through the search and you should get a variety of answers.

[my89240sx]

thanks for the help and the nice welcoming...great group. Is my 89 the POS model of the 240? I never have these problems with my good ole 72 early bronco.