Trying to free up piston rings.

[sutor623]

Been working on a 150GT and had to pull the exhaust cover to fix some small leaks. While I was in there I inspected the rings and cylinders. Pistons have minimal scuffing, bores look good with crosshatching still present.

Starboard rings look excellent. There is no carbon present and the rings spring right back out when you press in on them.

The port pistons have considerably more carbon on them. The rings were all stuck pretty good, and after some sea foam and sea foam spray I have gotten all three top rings to come loose. There is still carbon in the ring seats.

The bottom (smaller) rings are all still carbonized in place pretty good. I am wondering if I should keep soaking or just put the exhaust plate back on and do some decarb cycles. I think the lack of heat is my issue here........

 

[gm280]

Personally I would NOT put it back together until all the rings are free. I would keep spraying and working with them until they are free. But that is just me...

 

[sutor623]

Gotcha. Is there any types of tools that I could use to help without damaging anything?

 

[sutor623]

Ok, so I pulled the intake bypass covers and the rings are free and springy on that side.

I have hit the exhaust side with sea foam (can) in a spray bottle and sprayed and let soak (repeat) for 4 days now. I also hit them with sea foam spray, and tried carb cleaner and a toothbrush. I took an aluminum pin and gently tapped each frozen ring with it. All of these efforts have done little to nothing for the carbon buildup. I tried a heat gun and the aluminum just dispersed the heat. I’m at a loss here fellas. Not sure I can’t do anything short of pull the pistons or just run it and let it get warm and do a few soak cycles. I think heat would do the trick here.

anyone tried pouring hot liquid into the site?

 

[thatone123]

I've read qute a bit on this and there seems to be little consensus or a good or best way to do it. I believe they make some commercial preparations that some say work. I read where one guy was saying he put something on the rings and it softened the carbon so that it could be cleaned out. I know starting fluid (ether) will clean a lot of things that carb cleaner won't. Because of environmental regulations a lot of harsh but effective cleaners for such are not allowed to be made anymore from what I hear.

 

[flyingscott]

Are you positive carbon is the problem? You could try an Acetone ATF mix to free up the rings. Mix up a 50/50 mix and pour it on and let it soak.

 

[racerone]

How many hrs are you going to spend trying to free up the rings.-----How many hrs to take motor apart for a proper cleaning and inspection.-----I say take it apart and build a happy motor.

 

[sutor623]

Are you positive carbon is the problem? You could try an Acetone ATF mix to free up the rings. Mix up a 50/50 mix and pour it on and let it soak.

Scott, yes I am 100% positive that the issue is carbon. It is just the lower rungs on the exhaust side of starboard head. If there were more rings or if the entire ring was bound I could justify pulling the pistons but I just can’t quite justify that at this stage.

you can see the carbon buildup on that particular part of said pistons and that’s the only spots that has the buildup. You can also see the carbon inside thenring
grooves.

but like i said, I got the upper rings free because they were hemmed up too!!

 

[Sea Rider]

Buy a can of CRC Power Tuner Carbon Remover Spray and spray an overdose of product on both piston/ring sides, let soak for some minutes. Apply product on a hard britle brush and brush off piston/ring sides, repeat process untill it's cleaner. Be aware that if it's a 2 stroke filthy machine product will only remove partial carbon build up inside piston grooves.

If wanting to remove all the carbon already built there will need to open the crankcase pull the crankshaft out, remove rings and mechanically remove all carbon built up inside piston grooves. Is the cylinder head still bolted to the crankcase ?

Happy Boating

 

[racerone]

There is only one way to correct this problem.-----the " mechanic in a can " does not work very well.

 

[sutor623]

Hey sea rider. The motor is still fully intact, aside from exhaust cover plate and intake bypass covers. Heads are still on.

Pistons have minimal scuffing and cylinder bores look good from what I can see through exhaust/intake ports.

Once I pulled the intake covers and realized that the rings were all free and not broken I became more dedicated to cleaning the exhaust side with the motor intact.

compression readings are all good. I don’t care if the ring seats are squeaky clean, I just want the rings to let loose from the pistons so they can do their job.....

 

[sutor623]

Racer, I am not in a position to pull this motor apart. I am hoping that if I can’t get them free in 25 degree weather, then I can run the motor and do a few rinse/repeats. I mean don’t most guys just do a decarb cycle to free these things up??

 

[racerone]

The shelves are loaded with " mechanic in a can "------People buy the stuff all the time !!-----Just like fishing lures----" only have to catch fishermen " in my opinion.

 

[Sea Rider]

Can't put all products in same sack under a mechanic in a can. Seafoam aplied once does nothing compared to what CRC Power Tuner can do for piston rings, much better if applied directly. Can is bargain cheap, nothing to lose, try it out it's an amazing product.

Take advantage to clean all water paths located under the exhaust cover specially if engine was/is used in salt water. If going more deeply as a general maintenance DIY work. Remove cylinder head, mechanically de carbonize piston heads and back of cylinder head, clean all water paths in thermo, crankcase and cylinder head areas to perfection. Engine will cool much better. Will need to install a new head gasket if old is found dried, hardened....

Happy Boating

 

[sutor623]

Thanks sea rider! I have some engine tuner on the way.

 

[Sea Rider]

Sutor, how many cylinders and carbs does the 150 engine have ? Do you have ear muffs ?

Happy Boating

 

[racerone]

?----That would be a V--6 with 3 carburetors and 2 throats per carburetor.

 

[F_R]

Carbon is an element and cannot be dissolved any more that other elements such as gold or platinum can. Those mouse milk products work (if they do at all) by dissolving the goop that is holding the carbon particles together.

Good luck with your goop project.

 

[racerone]

F_R---------Hope springs eternal.-----I guess we can not blame folks for trying.-----It is said that there are 20 million pounds of gold dissolved in ocean waters.-----I have instructed the grandson ( 8 years old ) to ----" figure out a way to get it out "------He is working on it.

 

[Faztbullet]

I have had very little success freeing coked in rings with a cleaner.I have soaked pistons in just about every product made: Carbon Guard,CRC,Powertune,Ring free, rat **** and usually end up just breaking the out in pieces and bead blasting piston.Crossflows are extremely bad about this. If it was mine I would teardown and inspect and replace /clean pistons.