Stuck Rings?

befarrer · Post by **befarrer** » 04 Apr 2020, 10:26

I decided to do a compression test on my 98 V70 LPT, it has 240,000KM on it, runs fine, starts fine, etc... I had the following compression results on a cold (7C temperature) engine:

1 - 150PSI
2 - 130PSI
3 - 160PSI
4 - 160PSI
5 - 160PSI

All 5 spark plugs have about 6000KM on them, and all are the same normal color. I added a bit of oil into cylinder 2, and compression went to 160PSI, so I have no valve issue.

I have only owned this car since last fall, it starts no problem, even when its -30C outside and its not been plugged in all day at work, runs smoothly at idle and all the rev range. Oil consumption is 0.5L in the last 4000KM or less, I think most has been from leaking from the turbo inlet connection from the PCV, likely due to the lower compression on the 1 cylinder (PCV is all new and serviced as well) causing higher than normal blowby gasses.

I don't know the history on the car, other than the Volvo service stickers under the hood, and from what I gather is this car drove lots early in its life, the first timing belt was done at 128,000KM in 2002, I bought it with 232,000KM. Also, the tires were near new and had a date code of 2008 and were flat spotted, telling me this car has sat with little to no use since 2009 at least. I am wondering with this sitting and little use, I may have stuck compression rings on one cylinder? If the cylinder was damaged, I would notice oil consumption, if the engine was worn out, all 5 cylinders should be similar, if it was valves, oil would not boost compression. Has there been any issues with rings sticking on these engines?

Post by **erikv11** » 04 Apr 2020, 13:27

Not many reported issues no. But still could be. I might get it out on the highway and run it above 5000 rpm for about 5 minutes, you'll need to keep it out of drive to keep the rpms up. Check compression warm and cold after that. If cyl 2 still low then consider Seafoam or MMM or other stuck ring chemical tricks.

Sounds like a nice car.

befarrer · Post by **befarrer** » 04 Apr 2020, 13:37

That is what I was thinking, drive it hard. Now that winter is starting to loose the battle to summer, I might be able to. Still 2ft of snow on the ground, below freezing as a high, and snowing here though.

Post by **misha** » 04 Apr 2020, 15:02

0.5l per 4.000km is nothing.
One liter/10.000 km is normal depending on what oil viscosity is in the engine.

My car used 1l/10.000 km from the factory on hard driving.

Tyres made in 2008 are now for junk since tyres have a lifetime 8-10 years.
After that...they become plastic.

Post by **E Showell** » 06 Apr 2020, 13:22

Reminder me never to move to Alberta.

Stuck rings are a possibility. Abscate has a secret sauce to add to cylinder bores to free them up. Perhaps he'll share.

Post by **abscate** » 06 Apr 2020, 19:08

Half acetone half ATF by volume.

In Alberta this might be solid if it’s isn’t summer.

Warm the mixture with heat from an idling nuclear reactor.

Post by **erikv11** » 07 Apr 2020, 10:05

More detail please!

Acetone and ATF are immiscible. You can make it briefly an emulsion by shaking vigorously I've done that when using on stuck fasteners, but how do you make a mixture for adding to the crankcase or bores? The acetone and oil phases separate so quickly.

Post by **abscate** » 07 Apr 2020, 10:31

erikv11 wrote: ↑07 Apr 2020, 10:05 More detail please!

Acetone and ATF are immiscible. You can make it briefly an emulsion by shaking vigorously I've done that when using on stuck fasteners, but how do you make a mixture for adding to the crankcase or bores? The acetone and oil phases separate so quickly.

You shake the hell out of it for a few minutes, then dump it into the cylinder. Some of the oil/ATF will dissolve into the acetone phase, and that will carry into the cracks and lubricate. It will not make a clean, uniform solution, correct.

Post by **amblerman** » 07 Apr 2020, 11:33

How do you use this? I know you pour it into the cylinders. How much per cylinder? How long do you let it sit?

since you're adding a liquid to the cylinder, do you have to extract it eventually before firing it up?
Will this get into crank case and therefore require oil change before any actual miles on the car?

I guess these are fair questions for any "in the cylinder" treatment

Post by **abscate** » 07 Apr 2020, 12:56

I stuck about 100 ml into Cylinder 5 on evita to free it up

It sat for about three days before it worked.

Acetone will evaporate off really quickly, the ATF will help your engine automatically shift its cylinders.