Beer

I just seafoamed my 97 Cherokee with 120k on it and there was little to no smoke that came out of it. I got Deep Creep which is sea foam in an aerosol can and sprayed it down the throttle body with it running at about 2k-3k rpms. After 3/4 of the can I shut it off, and started it up again and ran it... No smoke. So I pulled the brake booster and sprayed the remaining 25% down there, no smoke when running. I stopped it again and after 10 minutes of sitting when I started it back up there was still no smoke.

Did I do something wrong, or do I just have a clean engine, or what?

95Cherokee

Exact same story with me. 95 with 115,000mi., no smoke.

Took the valve cover off and it was so clean under there you could eat off it so I'm guessing there was just no crap anywhere in the engine to be cleaned out, just my 2 cents.

XJEric

the smoke that you see spitting out from the exhaust is all that carbon build up in your engine finally coming out. If you dont have much smoke, perhaps you dont have much build up. Now, this doesnt mean (if you went in your crank case) you shouldnt change your oil. You can leave it in for about 100 miles but after that it needs to be changed.

Also, you dont want to seafoam often. I believe every oil change is about the limit. Seafoam is a great product but it is very strong and can damage seals and other various parts internally.

brandon402

Ive never messed with the stuff myself, and am hesitant to do so with such an old motor (ive got 258k on the odo). I know, in some instances, the build up that may exist in or around an engine is preventing leaks and, for lack of a better term, holding things together. If one has never used seafoam, would you guys recommend it?

XJEric

You wont be really breaking into those leaked if you do it thought the booster and or throttle body. You are referring to more the crank case. Seafoam also is recommended going through the gas tank. I usually do third in the booster crank case and gas. Go half in the tank, and booster. You run the risk with anything in an old motor but if its running up to par, id say you are ok.

brandon402

Ah, ok. And yea, thats how i was thinking too, if shes running good right now there isnt a reason to go monkeying with it. Other than crappy gas mileage, its amazes me how she purs after doing standard preventative maintenance actions.

XJEric

yessir, no need to possibly open up a very large and inconvenient can of worms. Any idea whats causing the lowsy milage? that may just be a symptom of an old motor i guess.

95Cherokee

My oil filter adapter starting leaking a little more after sea foaming, but it could also be the fact I put fully synthetic in an engine with 115,000 miles, IDK.

brandon402

Nope, no clue what it could be. I just assumed, as you said, probably a symptom of an old motor. My exhaust is also screwed up (i think my cat and muffler are toast) so the lack of back pressure could also be a part of it. Again, not really a huge concern. As long as she gets me from point a to b through the snow, im happy.

Full syn huh? I wouldnt recommend that at all. Any older motor with high mileage I would recommend a castrol blend at most. I would recommend a straight up regular oil over that, to be honest.

cherokeesteve

I watched a guy clean the combustion chamber like you described and loosen some carbon in the combustion chamber and get stuck in one the rings and start knocking, to say the least we did not do tune ups that way anymore.
Here in California they will not let you do that kind of tune up anymore because of the smoke and the adding to smog.

XJEric

To be honest, i haven't bought my cherokee yet, ive only been on here since i am (hopefully) buying one that needs a little TLC in a few weeks so i dont know any of the specifics of the cherokee models yet. I dont recall if you said what year yours is, but if your exhaust is messed, it could be throwing readings a little hay wire. I had a toast post cat o2 go in my Mazda and my gas milage was down to about 18 mpg (normally gets 25-28ish). Sorry to stray off topic.

Seafoaming isnt the best way to do a tune up, but i would say it has its miracle jobs. Ive seen many VERY bad idle issues corrected, MPG issues corrected, noised, ect fixed. Ive also seen it cause a lot more problems then what was originally there -- but thats a little more on the uncommon almost rare side (from what ive experienced). I am more familiar with imports and euros though. Not too sure how these motors respond to seafoam compared to these guys

JrRifleCoach

My 92 Laredo has 106K. Never got better than 17mpg. I ran 1/2 can in the brake booster line until it stalled then split the remaining between the crankcase and fuel tank. I made sure the engine and cat were hot before adding the stuff. After a short wait (5 min) we ran up to 55-60 and hel it there for about 5miles.

I swear that engine is quieter than before and the mileage bumped up 2mpg.

SpitFire

where is exactly is seafoam suppose to be added? Gas tank/Oil ..ect.

XJEric

You got it, the gas tank, crankcase (oil), and vacuum. Some people use the throttle body for vacuum. others use brake booster. Just have to be careful with the booster and throttle body and take it easy pouring it in there. vaporlock is no bueno. When you add it, and the engine studders and shakes a little, hold off. Then it will rev up and you can add more.

1990cherokee

Sea-foam is an outstanding product. I use it in my Cherokee and my dodge ram. You can put it in your oil and forget about it, no need to change it afterward cause it evaporates and ends up cleaning the oil out of the intake manifold. put it in with your tank and you will see a huge difference in the MPG. I put half the can in my gas and half the can in my oil. Works wonders. If you are scared to be doing sea-foam with your oil you can substitute 1 QT. MMO and it will do the same thing its just less aggressive about it.