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Discussion Starter · #1 ·
i have my carbs and intakes off cleaning them and my intake valves are pretty built up, would it harm anything to spray some seafoam deep creep in there and let it soak for a week or so til i get my carb parts in and together?
 

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I wouldn't. A solvent type liquid put in the passages is going to end up in the cylinder bores, valve guides, ring and groove area and wash away oil. Things will be a bit dry for the next start up. Some liquid may/will eventually get into the oil in the sump. The sea foam will not disolve carbon or rust (on valve stems and seats). If some deposits/crusties did get loosened up they could end up jammed between the valve head seating surfaces and the seats.



In other words the procedure probably won't do much good at all and may do some harm.



Hoppy
 

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Make sure the valves are in a closed position and there should be no harm.Then flush out with Carb/Brake cleaner and dry out with some Toilet tissue.

I have,in the past,done liquid top-end de-cokes using old brake fluid which is great for breaking down carbon.Half a rattle can top full down each plug hole.Spin engine on kill switch(No firing) a couple of times.Leave overnight and then fire up and blast out in the morning.



If you suspect the top-end requires a de-coke a full manual one is the best way but also if you can get and keep the top end clean by correct plug colour/mixture(grey/tan) and the above you can go well over 70,000+ miles without a need to de-coke.



Carbon build up is almost always because some one has not kept an eye on their plugs/mixture and are running rich.Things like a blocked/old air filter can cause this.



You can buy shop bought liquid de-cokes but as above there are cheap alternatives.I always keep my old brake fluid for jobs like this and also if you have small brackets and bits you want to strip for painting it's great for dissolving paint and rust.Also using it as a 50/50 mix with Acetone makes a super rust release penetrating fluid better than shop bought
 

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I would be more inclined to say that the build up on the intake valves(valve stem side) was caused by worn guide seals.
 

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Outboard Boat engine manufacturers sell a spraycan of carbon cleaner. I've used it many times successfully.. run the engine and sprayinto the carb throat while keeping the throttle open enuff to keep it running. Then leave it set and soak for ann hour or so... upon starting the lossened carbon will be blown out the exhaust. it works very well on 2 strokes... it should work on 4 strokes too.... just a thot
 

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Well, if it was me, I would get a new set of valve guides/gaskets, head gaskets.... then pull the heads off. Of all the things I have done on my bike, cleaning and palling the valves was probably the easiest. Heads come off with the engine still in the bike, pop the valves out and clean them (a wire wheel, brass preferably in a drill press cleans the crap of the valves fast, and wont damage the faces). Then get a bit of grinding compound and lap the vales.



I did both heads which took me all of 2 hours to do (actaully 4, 2 hours work and 2 hours because the wife wanted to help lol)
 

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Discussion Starter · #7 ·
K guys, i'll just wait and prob seafoam when I get it runnin
 
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