Seafoam in the oil...safe?
 

It was suggested in another thread that I try Seafoam, which I have in the vacuum line, and gas tank. I haven't added it to my oil yet. I have been reading various posts on various sites, and there seems to be some concerns about adding Seafoam to your oil. Has anyone had any issues with this? My car is a 2000 Honda Civic VP (dx engine) with 183,000 miles. I get regular oil changes. My thinking is to add the Seafoam to my oil on Friday, and I am getting my oil changed Saturday morning. Or should I skip this step?

My only knowledge of seafoam is that it is recommended you change the oil within 500 miles if you do use it in the crankcase. And quite possibly the sparkplugs if you use it in the fuel tank. It's not supposed to stay in the oil, it's to clean out any buildup so changing the oil only seems logical. The sparkplugs could be a concern if it starts missing after you use it in the fuel tank, it could foul the plugs.

yea you should be ok if you put it in before work and then change the oil sat.

From experience, you want to go through a couple warm up cycles (20+ miles) if you expect the sea foam to do anything.

An alternative to this is to use a solvent, thoroughly drain the oil from the crankcase, install the solvent, and manually work the oil pump for 10 seconds, repeating 10 second bursts every 5 minutes or so.

If you drain the solvent and it comes out cleanish, put in some cheap oil, then flush the block with itto remove any leftover solvent. Add your new oil and filter, and your good to go.

I will get a few warmup cycles in. I was reading that you want to put it in while the enhine is cool as not to shock stuff...That didn't make sense as when I get oil changes, my car is using warmed from having driven to the shop and the oil being added is cold...
But I will add the Seafoam tomorrow morning. Drive to work (13 miles). Drive at lunch (1 mile). Drive home (13 miles). Drive to karate (2 miles). Drive home (2 miles. Then drive to the shop for the oil change (20 miles). So that should give it some time to work.

personally, when a car starts getting a higher amount of miles, and never had that kind of solvent cleaning before, it's best not to do it now.

Some of the buildup in the motor might actually be beneficial to the longevity of your oil pressure and bearing surfaces. If you effectively clean out the motor, you send larger bits of debris thru the system and also increase the working clearances on the bearing journals, which may cause an oil pressure drop after such a cleaning.

I vote don't do it.

Zonker's on point here, and the Seafoam bottle itself states it's "not to be used on vehicles with over 150,000 miles."

However, it's not definitive. Here's a link I've bookmarked with compression tests before and after seafoaming a civic

Seafoam on high mileage engine - Compression results - Honda-Tech

at 198,000 miles, I'm hesitant too!

You need to ask why you want to do this.

I've used Seafoam in the crankcase to free up a sticky lifter, and it worked. But to do it just for the hell of it? I think it's OK but what is it going to do?

I haven't done it. I just figured I would do it to clean out the gunk in there, and maybe make my engine run a little better and keep running better. I am hoping to get a lot more miles out of this car. I have been told these newer Honda engines can get up to 500,000 miles.

Look under the oil fill cap and down into the valve cover. Change the oil and look at the plug, the drain oil, and the filter. A lack of condensation (milky white) and/or gritty sediment pretty much means all is OK in there.

I have looked at the bottle. I am not seeing anything about not using it on vehicles with over 150,000 miles.

if it isn't broke, don't fix it. Spend your extra money on a good oil like Mobile 1

I've used Sea Foam on several different cars, all of them over 140,000 miles. One of these had been badly neglected, so that it took a coat hanger to scrape the sludge out of the oil pan. I ran a change of cheap oil for about 500 miles, drained it, put in some more cheap oil with a whole can (NOT the recommended procedure!) of Sea Foam, ran it gently for about 10 miles and drained it into a clean pan.

I figured if it looked good, I'd pour it back in. It looked like ink. Completely black. So I replaced the filter and put more cheap oil in it with Sea Foam. This time, after about 50 miles I drained the oil and it looked normal, so I guess it had done whatever cleaning it was going to.

I don't recommend this procedure unless you have a motor that's badly gunked up, and even then, you have to be ready to give up and tear it down. I figured the Sea Foam as a "kill-or-cure" solution, and it cured it. If you use it as recommended, it should be safe enough, though.

I used some in a motor that was in better shape, and it didn't seem to make any difference.

If you want to gently clean out a motor, and keep it clean, use an oil mixed for heavy-duty diesel engines. Shell Rotella, Mobil Delvac, Chevron Delo, Valvoline Blue, there are others. They have strong additive packages, and are made to control sludging in engines that put more soot and crud into the oil.

The HDEO (Heavy Duty Engine oil) will clean the engine out slowly, so you don't run as bad a risk of dislodging something and having it block an oil passage. Plus, they tend not to be as expensive (at least in a synthetic) and you can safely run long OCI with them (use oil analysis to verify). They usually have a cheaper 15w-40 dino that works ok in hot weather if it's compatible with your engine, and a 5w-40 synthetic that works year-round in most motors.

I've used 0w-30 and 5w-40 in the same motor and not noticed any mileage difference, but there were other variables involved. I will say the engine keeps the oil pretty hot, so that might reduce the impact of the 30w vs. the 40w. The 5w-40 does make the engine idle quieter. I think it's valvetrain noise that's different.

I ran the 5w-40 Rotella T6 for 5500 miles, and it still had a good TBN (total base number-the oil's ability to neutralize acidic contamination), flash point and viscosity. The oil analysis guys recommended trying a 7500 mi OCI. The 0w-30 Mobil 1 at 5000 was used up (TBN, viscosity and flashpoint all at the limit), and they recommended not exceeding 5000 miles.

Since the 5w-40 is longer-lasting and cheaper, I'm going to stick with it. (8 quarts of synthetic at oil change time is no joke!) The 0w-30 is a gas-engine synthetic oil, not an HDEO.

I think Rotella (and maybe others) is also available in lighter weights that still have the strong additive package.

OCI = oil change interval??

Yes, sorry. OCI is oil change interval. Another one for the glossary, I guess.

just to be fair, when I was a kid I payed for school changing oil in an esso station. We had a pre-change additive that we would add to very dirty oil, idle the car, and then drain and flush out with another litre of oil.

the stuff worked great even if we didn't know what it was. I happened to catch the supplier one day and he told me that the additive was nothing fancier than a diesel/kerosene mix, and that adding a cup of diesel to the oil before a change would do essentially the same thing.

having added diesel to my car before oil changes regularly I cant say that I've ever experienced a negative impact.

i would use the diesel cautiously i would think it would be easy to ruin a bearing. im not saying i havent done it ( i have on a few occasions ) but wouldnt drive it add it and run a minute or two and then service. im with frank if you service it normally there will be little to no build up anyway. so your gaining little to nothing with it.

General Literary Rule: Always spell-out ALL contracted/acronym words the first time they are used, followed immediately by their contraction/acronym inside parentheses. There after, use the contraction/acronym alone.

drv2die I would tend to agree with you as far as driving the vehicle with diesel in the engine. I mean if the gas station is a block away from where your changing the oil, not a big deal. I certainly wouldnt be driving farther than that. I suppose I should of qualified how long to run the engine as well, certainly not more than 5 minutes, and usually 2 is plenty.

In the link you posted, the Original Poster's math is wrong. After the seafoam treatment there is a 20psi difference between cylinders: 195-175 = 20psi. (as opposed to the 27psi difference before seafoam).

Just wanted to point that out.

Or the entire engine.

Diesel has a severe impact on oil viscosity, making it so thin that lubrication is compromised.
If you run diesel in the oil for cleaning purposes, don't run too much for too long !