Water cleaning of combustion chamber (unwanted)

[xirdneh]

Classic result of water leaking into cylinder due to head gasket failure

[gmeddy]

so is it a good thing to spray some water into the air intake while engine is running?
I've watched a few vids on youtube about steam cleaning out the carbon from the engine, some guys spray a hose down their air intake while engine is revving around 2000rpms.
I reckon I have a bad buildup of carbon, causing the engine to keep running on for a long long time, literally 30 seconds after turning off key if i dont drop the clutch.

That piston looks nice and clean from the water!

[marlinh]

That is a really difficult thing to do. You would use a very small vacuum hose to draw water in and only in spurts. That is what I remember from school but I have never had the guts to try it myself. Hydraulic lock is the worst case scenario.

[Petros]

You could do it that way, but if you get too much water while it is running you could damage the engine. Water does not compress like air. it does not take much.

I would pour some kind of solvent like Gum-out or carb cleaner down the carb and let it sit overnight, than pull spark plugs and rotate engine over a few times to get excess out. Put plugs back and fire it up,l it will blow smoke and carbon for a few min but than clean up nice.

[larry mcgrath]

The best route to go is pay a shop that has a SNAP-ON motor vac this is a great machine that WILL clean all the carbon from the intake runners,int valves ,combustion chamber ,ex valves ,and head. Also does a great job of cleaning the inside of the carb. Usualy runs about 150.00$ ,worth every cent Larry

[dlb]

i've never heard of larry's suggestion. $150 is a lot so i would probably only go that route if i were getting a lot of predetonation (pinging sounds coming from the engine when it is under load) and had ruled everything else out.

i have no experience with the water/steam cleaning but have heard what marlinh and petros mentioned so research it thoroughly before trying it if you go that route. you can try seafoam. i have used it by letting it sit in the combustion chamber for a few days. the exhaust pukes some heinous black smoke for a while but i honestly didn't notice any difference in performance. a member here actually pulled the head after doing a seafoam treatment, took pics, then manually cleaned it, and took pics again for comparison. it really illustrated that while seafoam does remove some carbon buildups, it is certainly not a miracle cure. here's that thread.

https://tercel4wd.com/forums/viewtopic.php?f=4& ... oam#p57673

however, i haven't experienced dieseling (that's what it's called when the engine runs on after you've shut it off) due to carbon build up. it's possible but i imagine you'd also have high compression results and/or predetonation. maybe check for other common causes of dieseling too: incorrect idle and/or fast idle, ignition timing, vacuum leaks, i forget what else.

[larry mcgrath]

dlb I was a snap-on dealer for 12 years and sold several of these machines, you would'nt believe how well these work. look up snap-on motor vacume on e-bay there are several for sale ,from 700.00 to 4,500.00 The cleaning fluid is un-believeable Larry

[dlb]

i just looked up 'snap on motor vacuum' on youtube but couldn't find anything. i'm intrigued and want to see one in action.

in a nutshell, what is it and how does it work, larry?

[larry mcgrath]

This is a machine that is filled with a carbon cleaning fluid,and gass which is pumped into the carb under pressure (which is adjustable for high pressure FI systems ) the engine is run at around 2000 rpm till it burns about 1/2 gallon of gassand cleaner , which cleans the system. I looked this up on you tube, with no luck. The machines are for sale on E-BAY. One of my customers did this to my 84 sr5 that had about 150,000 miles on it,made the engine run dam near like new. This machine is highly recomended by PBS Click-and Klack the tappet brothers (National Public Radio ) this is the most listened to radio program in the USA. A call in car repair show ,aired every Saterday.Larry

[splatterdog]

It's Motorvac. I love my machine. It paid for itself real quick and it really works. Cleans deposits all the way thru the engine, not just the fuel system. The detergent is supposed to be non combustible and forms a cleaning steam when it hits the cylinder. Idle vacuum levels can increase .5-2 inches from the process, that's when you know it's doing something. I've seen 10% mileage increases on cars with less than 100k on them Makes pressure testing on injected cars real easy too.

Oldschool way is seafoam down the carb(warmed up and running)to loosen things up. Then I follow up with distilled water. Carefully of course.

[larry mcgrath]

splaterdog how much did you charg to doo this???? Larry.

[splatterdog]

No real set price. Depends on hook up time. 60-80 if it's real easy or fuel lines are already disconnected. Vans and imports are usually harder=more $. I will often throw it in with a major tune up.

[Petros]

compared to the forces going on in a running engine, it seems to me what ever external pump or vacuum you apply seems incidental. Would not just pouring the same kind of cleaner into the engine accomplish the same thing? If so, what is that cleaner, and where can we get it?

Of course a big machine puts on a good show, but it seems entirely unnecssary to me. I have seen a youtube video of a guy using a "home kit" that connects to your fuel injection systems and feeds a large container of a yellowish liquid into the EFI system as it runs (liquid looks like orange Gatorade). It was supposed to clean the fuel system and injectors, plus the combustion chambers. Looked like a good idea, but this still leaves the throttle and intake manifold too. That usually cleans up fine with throttle body cleaner. I have not used it because my Tercel has a carb.

See this, a lot cheaper than buying your own Motorvac. This guy has a series of decent car repair clips too.

http://www.youtube.com/watch?v=bKGI9N_yWd0

[Petros]

I found a youtube clip on the Motorvac. though I am skeptical, the "mechanic" said several things that are factually wrong, so I remain a skeptic that you actually need a machine to do this service.

http://www.youtube.com/watch?v=o4bbMCOZ9aw

[marlinh]

The last shop I worked in had a fuel injection cleaner similar to that first hand held one. It is really meant to clean the injectors so that proper atomization occurs. Any other cleaning it does is just a bonus.

I've heard a few stories of improper use of a motorvac and a subsequent fire on a customer's car as well.