Strangest auto 'problem' I have ever seen..take a guess!

[TurboTravis]

This goes WAY back to 2002, but I wanted to mention it due to being an oil related 'issue'. The long story short is that I have owned several Toyota Supra's over the years and have worked on a few friend's, etc. Anyway, this was a friend's car that he recently purchased and wanted me to do a full service along with some basic mod's. 1993 Toyota Supra Twin Turbo, 73K miles, BONE stock. I replaced the timing belt, water pump, etc..got to the plugs (which I could tell had never been removed) and figured why not do a compression test since it's so easy on an inline 6..

I do not recall which cylinder gave what reading, but 2 were at 60psi, 2 were at 90psi, and 2 at 180psi. Rechecked several times, different gauge etc...same reading. A leakdown test gave similar results (meaning that the cylinders with low psi had high leakdown %). Keep in mind the car ran fine. So, I figured what the [censored], add a quart of Rislone (the owner agreed). Get this..with the Rislone, the compression was 180 across! I figured we would keep the Rislone in for an OCI, drain it, refill with only oil, and do a compression test to verify that the Rislone had did it's job..we do that...

THE COMPRESSION IS BACK DOWN TO THE ORIGINAL TEST READINGS!......add Rislone....BACK UP TO 180 ACROSS!

We repeated this several times. The car ran the same either way, but we kept the Rislone in it just because...

Take a guess! I have no idea.

 

[FCD]

It is possessed by the devil.
Needs holy water in the radiator

 

[GR_CoB]

I noticed similar results in my NA IS300 when I had it. I bought it with seized engine. Valves kissed the pistons after previous owner of IS300 touched someone's tow hitch in a fender bender. Tow hitch touched the exhaust cam and broke all exhaust valves into the cylinders... Anyways, changed the engine for the same 2JZGE with less miles and checked the compression. Was a bit low on two cylinders. After "Restore" compression evened out.

 

[WobblyElvis]

A wild guess.
The Rislone was making the oil thinner. This allowed the oil to get to places that plain/thicker oil would not get to while performing the compression test. Perhaps past the valve seals and to the valve face or splash lubrication to the oil rings. When the engine was running, Rislone was not needed as the engine speed was higher and the pump /lubrication system was doing it's job.

 

[Trav]

Too much beer IMO.

 

[skyactiv]

Here is what happened I bet. The Rislone cleaned the ring packs, just enough to make them free again and restore compression. Very short lived as it didn't last long.

 

[Smoky14]

I gotta stop by and get some Rislone on the way home, along with some beer.

Smoky

 

[StevieC]

I would take the spark plugs out and soak the piston tops with some sort of cleaner and let it soak and repeat this a few times in an attempt to clean the rings. Then do the compression test and see if the weaker cylinders are any better.

 

[CourierDriver]

take it to a shop for a second opinon....just kidd'N

 

[69GTX]

I have a friend that's been using Rislone in his oil Frankenbrews for the past 20 yrs. And he only runs very high mileage cars. He's had excellent results with all his cars. Not enough to make me try it....but it works for him.

 

[Eddie]

Exhaust valves hanging up until the RESLONE supplies just enough lucubrate to free them temporarily. Ed

 

[circuitsmith]

Wouldn't leaky exhaust valves burn in short order?

 

[Trav]

Sure would, if that was the case it would probably be intakes but you would hear that. The last time I heard of that was on the old Z28 with crossfire injection that had water ingress issues.
The TSB fix for it was to run GM TEC down each throttle body running then shut it off and let it sit for an hour, the install a scoop seal kit.

 

[Mitch]

back in the 70s the rislone rep would show up driving his mid 60s dodge with a 318. All he ever ran was straight rislone.

 

[maxdustington]

Originally Posted By: Trav
Sure would, if that was the case it would probably be intakes but you would hear that. The last time I heard of that was on the old Z28 with crossfire injection that had water ingress issues.
The TSB fix for it was to run GM TEC down each throttle body running then shut it off and let it sit for an hour, the install a scoop seal kit.


Between Crossfire and TPI, third gens had the coolest intake manifolds.

 

[Yah-Tah-Hey]