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Cleaning the inside of an engine

I recently had my 1991 Dodge D250 with a 5.9L gas engine serviced and they recommended an internal engine cleaning with a machine they hook it up to for $160. The truck does burn and leak oil and they said it would help both. I have seen videos on the internet with an HHO machine that some people swear by and others calling it a scam. What do guys think? Can it cause damage? I also saw videos of putting water in the intake with similar comments that it works or the guy is crazy.

My vote is “scam”, or at least, unnecessary. There are several products that you add to the engine oil that may help with sticking rings. Might be worth a shot, and they cost a lot less than $160.

I’d interested in knowing how such a treatment would help stop leaks.

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How much more will it burn and leak when they are done?

This service should not be necessary, do you believe there is sludge inside the engine?


Anything associated with HHO is a SCAM. As for engine ‘cleaning’, regular oil changes should do it. If the leaks are out of worn seals, you might try an oil for engine with high miles, it swells the seals a little, might reduce the leaks.

How many miles between adding a quart of oil?


I can’t say I know much about it but just using logic, can’t see how cleaning out everything (even if that happened) would help stop leaks. More likely they would increase. Only way it would help oil burning is if it freed up the rings a little. But more oil changes or a Seafoam treatment for $10 would probably be a lot safer and more effective.


This stuff is about as necessary as an enema for the average non-constipated person. As mentioned, there are some inexpensive engine cleaners you add to your oil IF you need them.

I used to add GM’s Engine Oil Supplement in past years. It was a detergent type of cleaner that would free sticky valves and rings if such was necessary. In those days oils had fewer additives in them.

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Agreed with the others. IF cleaning is needed, Seafoam will usually do the job just fine. And cleaning is not usually needed if you’ve even remotely followed the oil change intervals. It almost certainly will not repair leaks. If that worked I could just, like, flush some Tide through my valve cover and it would magically stop dripping. :wink:

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Why “fix” something that isn’t broke?

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Skip this waste of time and money.

As for water into the intake, that is a different type of deal. Dribbling some water into the intake on a running engine can help decarbon the top end of the engine.

The trick here is to not go overboard with the dribbling and hydrolock the engine.

Thanks for all the responses. I was also leaning toward scam or I would of had them just do it. The only thing that bothers me is a little blue smoke when I back up or let sit and idle. Will look into the Seafoam for sure. I have had this truck about 15 years and just can’t seem to part with it, been a good truck for what I use it for. Thanks again for all the fast advice.

Your valve seals probably got hard and cracked about 10 years ago, no additive will help that.

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“Engine cleaning” and hydrogen are two different subjects.

Fifteen years ago our BG additive dealer brought in and demonstrated an engine flush machine. It was a fantastic machine. Remove the oil pressure switch and drain plug, connect the machines lines and pump a special solvent through the engine for 30 minutes. After each service the filter in the machine would be replaced and the old filter from the demonstration showed much debris.

After the demonstration I asked how much this would cost the customer (there is some labor accessing the oil pressure switch on most modern vehicles), the BG salesmen said about $150. I questioned if it would be just as good to get 5 oil changes during the next 5 weeks? (that doesn’t sell services).

I wouldn’t necessarily call it a scam, but I don’t see how cleaning the inside of your engine would fix oil leaks or stop it from burning oil.

The only thing that will fix an oil leak is fixing the leak, although using high mileage oil might slow the leaks by making the gaskets and seals swell a little.

The only thing that will fix an engine that is burning oil is an engine rebuild or replacement of the rings in the cylinders.

Typically, any service that involves hooking up a machine to your car to flush something out, whether it be fuel induction service, a transmission flush, or some other service, is beyond what is called for on your car’s maintenance schedule, making it unnecessary unless the maintenance has been neglected.

There are oil additives that claim to “clean” the inside of the engine. The stuff likely has solvents that can un-stick rings and flush out crud much like the BG treatment. The BG treatment won’t reach the rings since it only flushes the oil passages and rings are splash oiled. The oil additives are added before a change, run the engine to warm it up and then do the oil change. Usually these additive swell seals so the leaks slow down. These are a band aid at best and snake-oil at worst.

Water through the intake can clean out carbon deposits. Mist it into the intake while the engine is running. My leaking head gasket cleaned the piston top really well… I prefer Seafoam, though.

I was fortunately advised by my Father and also my WW2 USMC aircraft mechanic mentor that the only thing you pour in your crankcase is engine oil. My mentor’s advice was if your engine was burning, leaking oil, or knocking it needed repair not a bottle of “snake-oil”! I had used 2 locations of a regional franchise many times for oil and filter changes with no problems except their offering of many bottles of “snake-oil”. If I had said OK my crankcase would have been overflowing! I have no problem using the “N” word. Not that one. The “NO” word. I went to a 3rd location where I will never return. I was informed the recommended 30,000 mile $130.00 engine flush would be due before my next service. My car was less than 5 years old and had just exceeded 27,000 miles. I used the “N” word. This was the place where the mid 20s at most kid was trying to sell me everything but a new car. This is the same idiot who handed me a printout of my cars factory scheduled maintenance informing me that the 12 month transmission fluid change was way overdue. I reminded him it was a M/T. He replied it was for the M/T. I tossed it on the passenger seat and escaped. When I arrived home I read it. ‘Automatic Transmission/Transaxle. Shift Linkage. Inspect and Lubricate if Necessary’. 12 months. I read my scheduled maintenance when I purchased the car. I ignored anything regarding A/T. If anyone employed by a business lies to me they have permanently lost my business.

If the only symptom is burning and leaking oil, concur w/the other here, this is a no-go. Don’t have it done. This procedure can make sense in certain situations. If the shop can actually show you carbon or sludge build up is causing a problem by removing the valve covers, or the oil pan, or a camera into a spark plug hole, then it could be worthwhile. But not just b/c of an oil leak and a little blue smoke out the tail pipe.

Suggest to use that money to change the oil a little more frequently instead. If you change at 5000 miles, start changing it at 3000 miles. And use an oem oil filter you buy at the dealership. That’s a better use of the cash.