Marvel Mystery Oil

[mklearl]

I've recently inherited a 1998 volvo penta 5.0gi. It has been sitting for 10 years. Before changing fluids and turning the key i have done some research and seen some have put mmo in the cylinders to soak and free any rings that may be stuck. Anyone have any experience or input on doing this? Also... How do i clear the oil out of the cylinders after soaking. I know i can just turn the key with the plugs out but do i ground the plug wires? Leave the plugs in the wires? Thanks in advance.

 

[BigCahuna]

You can pull the coil wire and hold it near a ground source to verify you'll get spark, while cranking the motor over. If you put more then a couple of ounces in each cylinder, put rags over the plug holes so you don't have a major clean up. I hope you don't have a full tank of 10 yr old gas in it. It probably won't run if you do, plus you don't want to gum up the carb with old stale gas.Before you change the oil, make sure it will run first,and that it will pump cooling water. Your a candidate for new impellers at that age.,,

 

[Mud]

^^what he said, especially about changing the raw water intake impeller. It's taken a set after all these years and is probably brittle enough to break when the engine is started. Then you get pieces of impeller into the cooling system. Also, before starting "prime" the cooling system with water from garden hose in order to avoid a dry start of the new impeller.

 

[ronbo]

Add a small amount(teaspoon) of MMO to each cylinder and let sit for a day. My snow blower blew an oil plug during a 4 foot snow event, emptying all the oil. Not knowing this I ran the blower and it seized. Did the MMO thing and it free the rings/piston overnight. I got the engine to run BUT In the end the engine was shot with blow by gases forcing oil out the engine crankcase.

 

[leroyd92]

it would be easier to pb blast in the cylinders but to each is own.

if the gas is really bad, ive had a lot of luck with as good of a drain as possible and the best high octane you can get to burn up the old gas... some will protest but its worked for the projects ive gotten into or helped with. i have the big fram fuel filters you can mount anywhere to make life easier. (or varnish comes loose )

other then that replace the raw water pumps and go boating...


my 3l motor had 7 year old gas in it and 91 made it run flawlessly right out of the box( after i couldnt pump any more from the tank)

 

[mklearl]

Great. Already ordered the raw water impeller kit. Thermostat too! I was wondering about the oil. It was changed before storing. I will change it but should i start it first with 10 year old oil in it? I know I'll get a better change with the oil warm but don't want to do damage. I'll be running on an eternal fuel tank to get it going. After that I'll be draining the fuel and filling with fresh stuff...150 gallon tank... I hope it's not full either! I'm going to get an external switch and attach it to the starter. This way there is no spark our fuel pumping with the ignition off(fuel injected) right? Still unplug the coil wire?
Thanks again for the input!

 

[BigCahuna]

Take a look at the dipstick for any water that might be there.If there is, change it before you try to start it.But if it looks good, pull the coil wire and crank the motor for 10-15 seconds to pump oil thru the motor. Then put the coil wire back on, and hook up the fuel can and see if it will start. Don't forget to have a water hose hooked up. See if it will idle by itself, if not you probably have to clean up the carb. If the gas tank id full with 150 gallons of gas, taking half of it out and filling it up with new gas with cleaner and octane booster should clean it up enough to burn it off. Trying to get rid of 150 gallons of gas will be tough and expensive. Have a couple of filters with separators handy also.There may be water in the first few gallons pumped from the bottom of the tank.,,