QuestionAntonio this is a all make engine question. I change my oil and filter at 3000 to 4500 miles in all my vehicles. I use Mobil oil the one that says good for 5000 miles. Well on my one truck I took the intake off and when I had it off I could see on the lifters a lot of varnish color to them. Enough that if they moved farther in the bore than normal they would stick. Now my truck does not get beat in anyway, no hauling, no towing, no over heating, no plowing, just moving itself around. Why is this happening and can I stop it from happening in the future? Also is there something you have used that you have had good results with that I could run in the oil to help clean that varnish out of there? My other question is, my other truck has a low compression cylinder, it is at 80 lbs and the other cylinders are about 120 lbs. I ran some carbon cleaner through motor thinking maybe carbon is in there and after I did about 2 months later the cylinder went to 120 lbs. Well just recently I decided to run more cleaner through and then drove it with the rpm a little higher than when daily driven to clean out and the compression in that cylinder went back to 80 lbs. I think there may be varnish in there to and making a valve stick a bit when I took it above normal rpm and with a little time it works its way back closed. Any tips on getting that valve closed again? Any tips for this would be great.
Thanks
AnswerHello Bill,
For vehicles with high mileage, i recommend using a high mileage oil, this will help protect the engine better then normal oils, designed for newer engines. It also helps prevent the buildup of varnish in the engine. Try switching to a high mileage oil.
There are fuel additives that can be put into your truck also that will help to rectify the carbon buildup problem.
Carbon buildup is caused by not burning all the gas going through the cylinders. This can be caused by many different things including using bad gas, driving around in the city too much, and not having enough spark in the engine, but the main cause of carbon buildup is driving too carefully.
Driving slowly and safely and carefully every single day puts a lot of pressure on the engine. Driving like a maniac isn't good for your vehicle all the time either, but occasionally it is good to break out of your normal rhythm.
When you go to pass someone is a great time to really get on the gas and pull ahead. It doesn't take much. 20 mph above your norm for a few minutes a few times a month should be enough to keep the carbon from building up inside the engine. If you do have heavy carbon buildup already though, you'll need to do a little more.
Before you start burning off the carbon you'll want to put a gas additive in your gas tank. I use one called Guaranteed to Pass, which is an additive that increases your chances of passing an emissions test. It does this by getting rid of the carbon inside your engine which interferes with the emissions test.
Different auto parts places will stock different brands, so I can't recommend this certain type, just see what they stock or ask the person behind the counter what they recommend. There are many different types but most work the same way, by making the gas burn hotter and burning the carbon residue right off.
(NOTE: NEVER Fill up at a gas station that is in the process of receiving a gas delivery, ((meaning the gas tanker truck is there and filling the stations tanks with fuel for the pumps to dispense)) When that is being done, it stirs up all the gunk and nasty grit on the bottom of the tanks bringing it to the top and then when you pump it it goes right into your tank and thus your engine, increasing carbon buildup and causing wear to the engine and fuel system. Don't be afraid to ask the gas station how long it has been since they last received a fuel delivery.) Normally you want to give the stations tanks at least 12 hours to settle after they have gotten a delivery to let the gunk and grit go back to the bottom.
Make sure you have a full tank of good gas when using the gas additive and follow any other directions on the bottle. Do not use the additive in anything less than a full tank of gas unless the label on the additive says to do so. Too high of a ratio of additive to gas can cause the engine to get too hot and ruin your engine. Many of the additives require that you leave your engine turned on for a certain length of time after adding it to the gas tank so be prepared for that.
After getting your gas tank filled and adding the additive, take a long drive. Drive for a while, the additive bottle should give you an idea of how long you should leave the vehicle running before turning it off. If you can do this before you're planning on taking a long drive it works great. You'll want to use up all or most of your tank of gas before moving on to the next step. If this takes a few days that's fine, just finish using up the tank of gas and move on when you're done.
Now that that gas is gone, fill up your gas tank again. Don't add any more bottles of additive at this point. If you did there's a small chance that you could make your engine too hot and warp your engine's head. That would be extremely bad, so just to make sure it doesn't even have a chance of happening, don't add any more additive before driving the vehicle really hard.
Choose a road where you can take your car. Your area will determine where you should do this. Pick an area will a few long straight-aways where you'll be able to safely accelerate rapidly. Hopefully you'll have an area where there aren't a lot of police officers as well. You don't have to go over the speed limit, but if it happens you don't want to get a ticket. A nice straight freeway with very little traffic works well.
If you aren't comfortable enough with your driving abilities to do this yourself, don't attempt this part. Ask a friend or family member whose driving abilities you trust to drive. If you aren't comfortable driving aggressively that can be dangerous and there's no reason to risk anything happening.
When you've driven to a good area without a lot of traffic and the road ahead is nice and straight, slam down the gas pedal. The car may choke a little depending on how bad the carbon buildup is. Keep going. You may even have a small cloud of gray smoke come out your tailpipe that is that icky carbon burning off. Don't worry about it.
If you have a lot of exhaust coming out in a steady stream and it is blue or black, stop accelerating immediately. There could be something wrong with your engine and you don't want to aggravate the problem by trying to burn off the carbon. Different colored smoke means different things. Blue, usually there's oil in your gas mixture. Black usually means you have bad valves in your engine. Take your vehicle to an auto shop and tell them about the color of the smoke and the amount. You probably have bad rings or need a valve job.
Unless there seems to be a major problem try to keep the car at a steady acceleration until its ride is nice and smooth. You may need to stop the car and then start over by punching the gas pedal again. This way you don't accelerate past the speed limit allowed on the road. It is the rapid acceleration part that burns off the carbon, not the speed, so don't risk a speeding ticket.
When the vehicle seems to respond to the gas pedal easily and undergoes no more choking, you've gotten rid of the excess buildup. Try to gun it occasionally each month to prevent more carbon from building up. A few minutes of consistent acceleration will keep your engine nice and clean.
If trying to remove the carbon buildup so that you can pass emissions you may want to do another course of gas additive to make sure the carbon is all gone and the car is going to pass emissions. If not, you're all done.
I hope this was helpful, Please keep me advised of your progress, and let me know if i can be of further assistance.
Thank you, Good Luck.
