DonkRado
NAXJA Forum User
- Location
- Charlottesville, VA
'90 Renix 4.0 ~36K on Reman.
The first time I ran a dry test, the numbers just kept dropping as I worked my way to the back. I figured out that the weak excuse for a battery was draining, so I jumpered it to my other car and kept it running. So, the voltage may've been a bit higher than standard, but it should be consistent for all cylinders.
Compression Test:
Cyl: 1 2 3 4 5 6
Dry: 130 120 140 135 100 110
Wet: 150 155 150 150 135 150
I added about 8mL of 10w30 to the cylinder for the wet test. When I started it back up, it was blowing pretty much the exact same shade of smoke as it does when it's smoking under regular use.
Ok, here are the splug plug pictures. Looks like #5 does have some sort of difference on the firing tip:
Does anyone have any insight here? I read up on some of the 'reading your spark plugs' pages, and for the most part I think they look ok. 1 looks a little heavy on the carbon buildup, and 5 has something going on at the tip. I'd be really interested to hear what anyone that has a bit more experience in reading them has to say. And what about those compression numbers? 5th cylinder looks weak, and the wet test bumped it 35psi. That hints towards blown rings, right? I'm going to try and put a compressor into the spark plug fittings to listen for air leakage today. First order of business is to Seafoam the intake and crankcase, then change oil and pull valve cover and clean CCV.
So, ideas? Thanks.
EDIT: Oh, and these plugs only have about 200 miles on them. Yeah, the threads are nasty on some of them. I need to try and vacuum out the plug hole areas or otherwise clean them. I noticed that some of the threads feel a little bit crossthreaded when putting them back in. Some didn't want to rotate nearly as many turns before going hand-tight. I guess I need to chase those threads, but I imagine that I need to clean the area first.
The first time I ran a dry test, the numbers just kept dropping as I worked my way to the back. I figured out that the weak excuse for a battery was draining, so I jumpered it to my other car and kept it running. So, the voltage may've been a bit higher than standard, but it should be consistent for all cylinders.
Compression Test:
Cyl: 1 2 3 4 5 6
Dry: 130 120 140 135 100 110
Wet: 150 155 150 150 135 150
I added about 8mL of 10w30 to the cylinder for the wet test. When I started it back up, it was blowing pretty much the exact same shade of smoke as it does when it's smoking under regular use.
Ok, here are the splug plug pictures. Looks like #5 does have some sort of difference on the firing tip:
Does anyone have any insight here? I read up on some of the 'reading your spark plugs' pages, and for the most part I think they look ok. 1 looks a little heavy on the carbon buildup, and 5 has something going on at the tip. I'd be really interested to hear what anyone that has a bit more experience in reading them has to say. And what about those compression numbers? 5th cylinder looks weak, and the wet test bumped it 35psi. That hints towards blown rings, right? I'm going to try and put a compressor into the spark plug fittings to listen for air leakage today. First order of business is to Seafoam the intake and crankcase, then change oil and pull valve cover and clean CCV.
So, ideas? Thanks.
EDIT: Oh, and these plugs only have about 200 miles on them. Yeah, the threads are nasty on some of them. I need to try and vacuum out the plug hole areas or otherwise clean them. I noticed that some of the threads feel a little bit crossthreaded when putting them back in. Some didn't want to rotate nearly as many turns before going hand-tight. I guess I need to chase those threads, but I imagine that I need to clean the area first.