VetteDrmr

There is one risk you need to be aware of, whenever you use any kind of liquid poured in through the intake. I know of one, only one, instance where a owner poured in the fluid too fast and hydrolocked a cylinder, OUCH!! One engine rebuild later he had a sad story to tell.

So, just make sure you don't pour it in so fast as to kill the engine. I just suck it in at a rate that causes the engine to begin struggling to idle. Then shut it down for an hour or so, then kill the mosquitos!

Also, top end cleaners can take a while to erode the hard carbon. I've seen improvements in knock retard up to 500 miles after I did the treatment.

HTH, and have a good one,
Mike

Rhode Warrior

I mainly used a scotchbrite pad and some elbow grease.

EStreeter

Thats a good point about not pouring too fast and killing the engine -
The instructions on the GM Top End Cleaner say to pour about 1/2 to 2/3 of can slowly and then more quickly to "stall the engine." Thats right - they said "Stall the Engine." They are talking about an engine with a carburetor and pouring through the carb however.

I ran a tube from the PCV inlet at the manifold to a funnel and clamped the tube off with a vise grip just enough to let the cleaner get sucked in slowly by the vacumm. Sort of like an IV drip. Worked out fine. It took a few minutes to get all the fluid in and then I shut it down for about 30 minutes.

After I started it and ran it to blow out the junk, you could wipe your hand across the rear end and see the carbon on your fingers.

It really works.

Dirty Howie

Rusty:

Besides being stupid I'm also color blind.......just kidding I did reread your original post a couple of days ago.

But I am surprized that he feels 15 minutes is going to remove 50k miles of carbon buildup .... like you see on the pistons in the post above.

GM Topend is 12 hours per the tech tips on the forum....


DH

Dirty Howie

Good to know!!!!!

Pour SLOWLY.
Are you saying that the carbon is still coming off 500 miles later..???
If that true shouldn't you do an immediate oil change and then another 500 miles later??

EStreeter: You only used 1 can for 30 minutes??? Seems like few are following the tech tip which says 2 cans left in over nite!!!


DH

EStreeter

When I bought the Top End Cleaner, the GM parts guy said their techs use it all the time and they usually use 1 can. My car has 25K on it and been breaking up on the dyno at about 4700 rpm. Its likie it has a miss fire or knock but everything checks out mechanically. I have tried a few different things and this was one of them.

There was a lot carbon on the rear of the car after the drive. I don't if I got it all but I plan to do another treatment before I go back to the dyno later this month for a tune.

Dirty Howie

I'm gettting my tune checked/adjusted in about 10 days....thats why I want to do the decarb also.

Nice car color.....

VetteDrmr

I haven't done it the way C4C5 suggests, pouring 4 ozs into each cylinder, leaving it overnight, turning the engine over with the plugs out, etc. I have complete trust that his way does the best, he's a pro's pro.

My way just sucks it through the intake, gets "burned" in the cylinders, and pumped out the exhaust. So, there shouldn't be much if any in the oil.

The top end cleaners first soak into the "soft" carbon that builds up in the intake chambers and the shroud of the intake valve. It also soaks into the "hard" carbon that's in the combustion chamber (just at higher temperatures). In both cases the vibration from subsequent running causes the carbon to loosen (I assume along crystalline boundaries) and erode, with the loose particles exiting via the exhaust.

Also, this procedure works best (seriously!) when you go make some hard runs. Remember you parents "blowing out the carbon"? I always thought that was a rather poor excuse, but turns out they're correct!

As far as the 500 miles goes, my '94 Z-28 (LT-1 motor) has a full time diagnostic tool wired in, which shows spark retard. First time I did the top end cleaner exercise I was pretty disappointed with the results. I "checked" the knock retard every week and found the retard values went down over a long period of time. In my case it took about 200 miles, but on other cars I've seen it take a bit longer. My point was, have some patience if you don't see immediate results.

HTH, and have a good one,
Mike

SLPRC5

Sorry Howie I had to go to RED to point it out to you. I was concerned with the mixed information on how to use Sea Foam, so I e-mailed the company and that is what the company rep came back with. The catch all is "everybody is right".
Anyway I used a can in the wife's Jeep with 79200 miles on it and let me tell you...while pouring it in it SMOKED big time. I let it sit 15 minutes fired it up...SMOKE..left my drive way headed out to the highway to run it out and believe it or not I was flagged down by the local LEO to tell me my car is smoking...I told him "I know..I'm head to the shop now". SO out to the highway..smoking all the way....got on it a few times running it up to 80+ MPH for about 6 miles. Smoke cleared up engine smooth out. Got a can and poured in the gas tank and will change the plugs that have over 30K on them..
When I used it in my Corvette...it didn't smoke as much...and cleared up in under 3 miles..leads me to believe there wasn't that much carbon build up.
Rsty

TomT

Does this stuff work if poured in the gas tank?
And if so, how many tanks does it take?

Cobra4B

You have a few options...

1. Run Seafoam or other top end cleaner
2. Sign up for a track event and blow the carbon out the fun way!

I drive my car hard and run 4/5 HPDE's a year. I had it dyno-tuned this past weekend and it showed no signs of knock or knock retard of any kind... runs smooth and the dyno chart shows that (see sig).

I think when I get to 100,000 miles (47,000 to go) I'll run some of this magic stuff through =)

grinder11

No, but it helped with spark knock.

SLPRC5

Good move

SLPRC5

Well I ran a can thru the vacuum port and a can in the gas.Changing plugs next. The milage sux on these '97 Jeep GC (15mpg at best)

Robbo

I have a 98 coupe with 125,000 on it and don't know the history (only owned it since 118,000 and August). I think I will try to cover all the bases. Anyone see anything wrong with this plan?

Pour half of one can in the oil ~250 miles before oil change is due and pour 1 can in the gas .

The day before the oil change I think I'll try the 4oz in each cylinder and turn over w/o plugs then let sit overnight. Next day will run the car until it stops smoking and then change oil and put new plugs/wires (don't know when the plugs/wires were changed last).

Any other related suggestions to go along with this that you would do with the mileage/unknown history?


Rob

Cobra4B

^ Sounds like a great way to freshen up an LS1 just reaching middle-age

jrizzuto

I used Seafoam to correct some stubborn pings, and it is the greatest. Only one caution when putting some in the tank....put it in while you are at the pump and immediately wash it down with gas.

My reason....i threw it in my tank without filling up and a day later, the o-rings between the 2 tanks started leaking. Now it could be a coincidence, so I'm not completely positive. But I think it's worth the extra precaution.

CentralCoaster

Similar thing happened to me. I sipped it out of a container nice and steadily. I recall the instructions saying to finish it off by dunking the brake booster hose completely into the seafoam to stall the engine. This didn't work (maybe due to vacuum leaks elsewhere?) so I shut the car off manually. Upon restart, it hydrolocked. Though it was a fluke, tried again but it was still locked up. Came back out 30 minutes later and it did start up and do it's smoking thing. I assume the fluid either evaporated or leaked past the rings. Unfortunately, I never checked the compression beforehand, but it's all but dead now.

2 cylinders at 50psi, 2 at 95, 4 at 120psi. Maybe some cracked rings, or a leaking head gasket.



Everytime I post my results everyone tells me I'm an idiot.

Dirty Howie

YOUR AN IDIOT !!!!!!!!


DH

CentralCoaster