I used Seafoam to clean my throttle body and intake system for the first time yesterday at 111K miles. I've owned my 90 SE since new, and by the time I knew that you should do this type of cleaning it had 85K or so mileage. By then I seen how much sludge buildup there was inside the intake manifold parts and was afraid to dump that much crud into the cylinders at one time. So I waited until after I had manually cleaned most of the crud out first.

Just before using the Seafoam, I had completed a two week project where I had replaced all Injectors, installed all new injector Connectors, all vacuum, fuel, and coolant hoses. Throughly cleaned the two upper intake manifold sections, Trottle Body, IACV valve, EGR Valve, and as much of the lower intake manifold runners as I could reach. Went through 3 x 20oz cans of Chemtool TB cleaner and wore out 2 wire brushes. Throttle body orifices that lead to the vacuum connections were completely clear and clean. No kinks in any vacuum lines. Did a 20 mile highway test drive and it ran great; Engine just purred at idle.

With the engine running and warm, I attempted to draw Seafoam in from the can with 2Ft of vacuum hose off the two (lower front) Throttle Body vacuum ports via two Tees I'd installed inline on these hoses during the above refit. Using 2Ft of vacuum hose, tried to draw Seafoam from both of these Tees. No draw even after 20 min. At that point I (again) searched this Forum on Seafoam, and found a comment that you could also use the vaccum nipple off the front of the Intake Manifold. When I tried that port, it pulled so much Seafoam it amost killed the engine before I could even fully insert the vacuum hose. So I just 'kissed' the hose to this port two more times. Checking the Seafoam can, I saw it had pulled in almost the entire can! (1/3 can recommended). Shut down the engine for the perscribed 5 minutes, restarted and blipped the trottle repeatedly getting all that white smoke.

After this, the idle was now very rough, and I was worried about the effects of that sudden intake of too much Seafoam. So I jumped into the car and headed for the highway intending to make sure all that loose carbon got burned and blown out before it settled into somewhere harmful. On the 1.5 miles to the highway, I could see a few puffs of white smoke from the rear view mirror. Once on the freeway at 65mph, huge clouds of smoke were billowing behind the car at least 10 ft, worse than any junker oil burner I'd ever seen. After my initial panic attack (Ohmygod that stuff has ruined some valve seals!!), I noticed that the smoke was white, not the darker bluish tinted smoke from burning oil. After 10 miles, the smoke decreased and swiftly disappeared. Another 20 miles, still no smoke.

Coming to the Point:

1) Is it normal to have no or very low vacuum at the two TB ports at Idle??? If not, what should I look into? If I had major vacuum leaks somewhere, the intake manifold tap wouldn't have emptied the Seafoam can in 3-4 seconds.

2) There is another 1990 Maxima in the family, my mother's GXE Autotragic, a 'cream puff' with only 41,000 miles, that I (lucky me) get to maintain. I had intended to Seafoam this car before it got to much sludge buildup. After what happened to mine, is it safe? I certainly need a better way to slowly feed the Seafoam into the engine if the TB ports don't work.

3) After all that cleaning during dissambly, could there possibly have been that much carbon or sludge left to generate that 'whale tale' of smoke?

Anyone with a similar experience? Comments would be highly appreciated.

 

yes. those 2 ports are before the throttle body, so vacuum only applies to them when the throttle is opened some, and none at idle. the ports on the intake manifold itself pull the most vacuum at idle, and gradually decrease toward WOT@redline

 

the smoke is part carbon and part seafoam burning out.
you used way too much...so you'll get more smoke.

i use a vac hose and pinch the line when i'm slowly feeding the seafoam in.

 

i just pour a pre-defined amount into a cup so i can see how much is being sucked in

 

should have just used gumout all in one.

 

My thanks to All for the comments. I thought those vacuum orifices were behind (downstream) of the butterfly plates, not in front of them - my mistake.

Of course I used to much Seafoam. I wasn't expecting it to draw an entire can in an instant. But enough stayed to go about 10 minutes at idle and 10 miles running over 3000rpm? If I had, I might have used a smaller cup or pinched the line or both. If I do the other Maxima, I think I may use a valve in the hose even if I have to use adapters to step up the hose size. Next time, I want a controlled SLOW feed of whichever cleaner I use for TB/intake cleaning. Since I already have a small needle valve, it would be worth the time to mess with hose adapters considering that I've got two cars do regular future cleanings. Don't want that nasty crud buildup ever again.
Nothing like experience as a teacher.

 

you can suck it in thru the hose that connects to the water cock solenoid on the firewall. it's a small diameter tube.

 

do a youtube search on seafoam. lots of people have sued too much causing the huge amounts of white smoke. the smoke is ordinary, as you'll see after youtubing it. but you jsut had lots b/c of well... you know already so i win't repeat it. once you've burned all the seafoam off etc and ran filled her up agan mind posting on any noticeable improvements it did?
ps you use any in your oil? ive heard of people doing that. also did you add some to the fuel tank aswell?

 

WOw I may have to try this method of using sea foam, exactly what did it accomplish, and did the car run better?

 

it basically cleans out the exhaust system and parts of the intake. It would improve slightly on acceleration, possibly improve fuel mileage, but would improve definitely on idling.

 

http://www.seafoamsales.com/motor-treatment/index.html

 

sounds like you are lucky that you didn't hydrolock your engine. You don't want to put the hose in and let it draw it out.

 

No, it didn't - but I wasn't expecting it to because I had already removed the majority of the sludge from Intake Manifold sections and Throttle Body during the teardown for replacing the fuel injectors. The two photos below show what is probably in your engine now, but I had already cleaned manually prior to using the Seafoam. Condensation from oil bearing PCV fumes + recirculated exhaust gas + fine dirt getting past the air filter over a long period




My purpose in using the Seafoam was to clean out the remaining sludge that I could not reach during disassembly: the last 4-5" of lower intake manifold runners plus valve seats and any carbon buildup in the combustion chambers. The Seafoam was just to finish the job so it ALL was clean. Then do this as regular maintence to prevent further buildup.

After reflection, I still may be able to draw from my two Tees in throttle body vacuum lines, but I'll have to blip the trottle to get it to draw since CapedCadaver straightened me out on vacuum at that location (none until throttle butterflys are opened). If not, I'll try the other suggestions.
I certainly can avoid what happened here - got caught by surprise.

I'm sure any drivers in cars behind me on the highway were convinced my car was on fire I wasn't kidding about a HUGE cloud of smoke trailing me at 65 Mph.

 

You are Precisely Correct. That is why I was very careful NOT to kill the engine during Seafoam feed, and immediately headed out to the highway for a hard run before stopping the engine. I was afraid of that very thing among others.

 

i was reading this when i woke up but were you saying that u put the hose in a container and let it suck it up?

 

When I seafoam'd mine, I just cut the bottom half off of a water bottle, and then sucked it straight out of that. That way I could watch the level and make sure to not submerge the line so much that it would stall the engine out

 

I don't think it is possible to hydrolock the motor with a combustible liquid unless you were pouring it in directly into the cylinders with the motor off.

Besides, when you would start it, the thing would most likely detonate like a **** and that would be the end of it.

Anyway, my suggestion to all who use seafoam is to gradually suck it out of a cup (as mentioned above) using the BRAKE VACUUM BOOSTER hose. All cars having power brakes (99.% of cars) have them, it has lots of suction, and the line goes straight into the intake manifold.

 

That's what exactly what happened to me the first time I tried Seafoam on my max....

Well what I have done is that there are two hoses that conect from the canister to the intake manifold. One constantly sucks air while the other hose has a vaccuum when increasing the throttle. I use the second one and let the throttle do the suckin.

I also tried the smaller hose that goes to the IACV. Is that good place to use it to clean it?

About that... is it REALLY a good place for the maxima? Looking at the pics of the manifold above the brake booster line will only go to only one side of the cylinders. Or will it go to all of the cylinders?

 

That's where I've always done mine

 

Ok, i took the seafoam challenge on my 3.0 sohc white max... i took off the vac line next to the fire wall which is my brake booster line. pour it in slowly while the engine was running white smoke came out...
1 poured 1/3 into my brake booster vac hose.
2 poured 1/3 into my fuel tank.
3 poured 1/3 into my fuel throttle vac hose " the one that leads down into the air hose which leads to your air intake.. its the hose where connects to your air intake tube..

CAR RUNS AMAZING!!!!!.

did this at a mechanic shop and the lead A-tec is going to use it in his car just because he knew my engine came from the junk yard and run like Shi* and now runs like it had been rebuilt idle is no more low and bucks. and intake throttle opens and closes amazing no more sticking!!!!

Over all seafoam Amazing and if you got any questions hit me up

 

i can't find seafoam anywhere here in Canada......

 

VBC = Vancouver, right? Can't you just drive to the US and get/use it there?

 

VBC=Vernon, British Columbia,(5 hours/400km/250miles) east of vancouver, not really worth it to drive down to the border... maybe i can ebay or amazon some of it... hmm.

 

Actually that's a completely backwards way of doing things.
1. you want a SMALL hose to keep the flow of solvent nice and slow.
2. you want the hose connected as far forward (just behind the throttle body) as you can. Connecting it on the back of the plenum only gets 2 cylinders out of the whole engine.

3. And YES, you can hydrolock an engine using any fluid. it's a matter of filling it faster than the air and a cylinder filling with enough fluid that it runs out of airspace before it reached TDC. The momentum of the crank and flywheel with engine running will cause it to bend a rod or shatter a piston almost immediately and it won't even slow down. you just hear a bang and it starts running rough.

I did that exact thing on an Infiniti J30 a few years back. the only vacuum inlet for the intake manifold is the brake booster line near the left rear cyl (can't remember if it's 5 or 6).. unfortunately it sucks a 1/2 bottle of goo into the engine in about 1/2 second and dumped it ALL into that one cylinder. BANG!! clack clack clack clack clack clack clack clack clack clack clack clack clack clack clack

Worse yet it was a customer's car I'd just finished a timing belt and valve cover gasket change on. I had to buy the guy another engine and wound up losing about $300 in that job just in parts since you can't pull 5 cam and crank seals off and reuse them. not to mention the valve cover gaskets and the PITA of changing the water pump and all the hoses. maaaaan that job sucked.

alll because I used the brake booster hose to suck down some Seafoam.

 

yeah people think because it is a combustible liquid they can put as much as they want. You really need to regulate it. The way I did it was pour it into the hose with vacuum so it sorta sucked it in like a mist.

 

F4 Phantom smoke trail....

 

CARQUEST

 

Stepping in to make a comment:

In addition to trying to de-gunk the TB, plenum and manifold, the idea is to loosen up and burn off the stuff that accumulates on the back of the intake valve, as well as top of piston and maybe even the head. Getting the stuuf in there in a controlled fashion, then letting it sit/soak in a bit after getting the internals wet is key.

 

I'm convinced seafoam didn't do very much for my high mileage motor. I'll upload some pics over the weekend pre-overhaul of what the pistons and etc... look like after 2 seafoam treatments within a yr. I think at a certain point the stuff is so caked on that drenching it in some liquid won't even do it. It needs to be taken off by hand with a combo of wire brush and compressed air (engine cleaning gun). Even varsol couldn't get some of it off - laquer thinner is the only stuff that worked for me, and loctite pro varnish remover, but I quickly stopped using that one because it adds up. It's 5 bucks a can but it's the strongest and fastest cleaner I've tried.

Maybe seafoam could be useful on an already clean engine though? By doing it every couple yrs?

 

That's enough to convince me to stay away from that stuff. In fact, I think I may have come close to your scenario - when the car practically stalls out when putting it in the brake booster...it's funny how I could have sworn I read something on the seafoam website to use the brake booster hose to do it, so I followed, and it sucks it up instantly.

 

didnt i just respond to a post of yours about when to start using seafoam???


are you saying that matts post was enough to convince you to never use seafoam ever????

you really should bump your post into this one, they really are close enough to the same topic.

 

your not removing any hardened sludge/varnishes with a quicky Seafoam treatment....

 

Hey whats up guys,

I'm interested in seafoaming my 89' GXE that has about 150 thou on her.
I did the injectors about a year ago and she wasn't to bad as far as build up
was concerned. I never done this to my Max cause I just didn't feel the need
but if this can increase life spand of my engine, throttle response and maybe
mpg I would appreciate any suggestions anyone might have to offer on doing
this to my max, thanks Shiloh.

 

Just seafoamed my intake system today and all went well, no smoke out the
exhaust or nothing. She always ran clean and was very clean to begin with.
Now tomorrow I'll try dumping some into fuel tank and see what happens.

 

no smoke? that's weird, it is actually supposed to smoke. I've used it ona my Z on my sisters civic, my old camry, all kinds of cars. I put 1/3 in the crank case a day or 2 before an oil change so when I do the oil change I get more out. 1/3 in the gas tank should smoke some but not much at all. Running it through the vacuum line you should start to see a little white out of the exhaust first then shut it off and let it sit. I've let it sit 15-20 min before and did an even better job on my sister's civic. Take the car for a spirited drive to really allow any deposits to break loose easier and smoke should go away pretty quickly. I've heard about using the brake booster but I generally use the vacuum going into the intake manifold directly, have never had any problems that way.

 

Out of the few times that I have done the Seafoam treatment on my Max, there was one time where it didn't smoke as heavily as the other times have. I dunno why as I have done the usual procedure. Maybe weather conditions, but whatever

Maybe I should do another round since it has been 14k miles since the last one. I'll do it on my next oil change on the next thousand miles.

 

the one time I did it and didn't get a lot of smoke, it smoked for like a week instead of 15 min, but mild the whole time.

 

I love seafoam. I would recommend it to anyone, just go slow and it's perfectly safe.