Little interpretation help from the experts needed..
I brought the car up to operating temp, then removed all the plugs. Then proceeded and here are the numbers I got. I'm running 20W 50 Supertech Oil.. Is this high compression?
Cyl #1 - 170
Cyl #2 - 165
Cyl #3 - 170
Cyl #4 - 160
It says on the compression check instructional to step on the gas.. I neglected to do that, but cant see how that would make a difference? I started it and counted 10 seconds for each cylinder.. Its a 3A engine with 117K.
Here are the pics of the plugs with 2K miles on them. They seem to have a stripe in them. Oil stain? Whats your take?
Thanks.
It is a good idea to just put a brick on the gas pedal and leave it there the whole time you are doing the compression check. Unplugging the distributor is a good idea also to prevent the possibility of damaging the ignitor.
If you did the comp check ft. to back, that lowest # could be due to a fading battery at the last. Not giving the battery extra reinforcement by jumper cabling it to the battery in a running car, or at least hooking up a good sized battery charger to it while cranking is a common oversight while doing comp tests. I'm sure that the 30 seconds of cranking that happened before you got to the last cyl. caused your battery to loose some cranking voltage.
The numbers that you got are OK. But without doing it again to get more more valid #'s you really don't know for sure.
The ST 20-50 should be fine in SW Florida.
Last edited by 4wdchico on Thu May 20, 2010 10:16 am, edited 2 times in total.
Ok, the pic of the three plugs appeared while i was typing the last post. Did you drive the car to get it up to temp or just let it sit? i would not depend on a plug reading done in a warm climate on a carbed car, like the t4wd, that was just run up to temp while sitting. In warm temps a carbed car will often have the choke on much longer than needed during warm up.
If you want to get a good plug reading, take the car out and drive it hard after it is fully warmed up. Then, at the end of a long hard pull, put the clutch in and shut off the motor, coast to the side of the road and pull the plugs.
Last edited by 4wdchico on Thu May 20, 2010 3:19 pm, edited 1 time in total.
I drove it around the neighborhood for about 10 mins to bring it up to temp. Then let it sit in the driveway running while I got the guage and tools to pull the plugs.. It was def up to temp becuase the fan turned on a couple times before I shut it down.. Weatherwise, It was about 85 degrees at the time I checked. Yes, those are denso plugs..
the compression looks okay, no issues. The spark plugs look a bit rich, the black stains indicate that. They should be light brown with proper mix and combustion. Are they the right heat range plug? too cool of a plug can give you black depoists like that too.
Not sure about the heat range. The plugs were what the index book suggested.. However, it could be running to rich. I have played with just about every screw on that carbuerator for the last year.. Sometimes, it idles wacky, sometimes it idles normal. It does a whole host of different things on different days depending on the outside temp and whether or not it took its prozac that morning.. I cant make Adam to Eve with that gosh darn thing.. I'm getting pretty good fuel economy, so I'm not complaining... Thanks for input.