YICS tool fabrication

Ok so I'm new to this forum so if this has been posted before don't kick me in the head or anything.

But not knowing exactly what the YICS was I decided to Google it to see if I could educate myself on it. And I found this in the process and figured it might be useful. It's a design for making yer own YICS tool for just a few bucks. If I'm stepping on any toes with this, move yer feet.

http://home.westman.wave.ca/~jbe/YICS.htm

 

No toes that I can think of. :wink:

 

Those instructions are wrong, they are missing the large (yet soft and oh-so-adherent) hi-temp rubber washer that goes on the end of the tool, by the 90-degree bend, which seals the YICS passage where the tool enters. Without that washer, you'll have a huge vac leak into the passage from the atmosphere, and at best, will never get your engine synched, or at worse, will end up setting the synch to unbelievably out-of-whack levels............

 

OK

The design is flawed. However, it could be modified and made to actually work.

Instead of three peices of hose, use four. Set each peice of tubing to sit under each of the four carb ports. Once they are compressed and thus expanded they would seal the four ports off. I don't know the precise measurements needed but I've taken the liberty of reworking the design.

If someone could just provide the missing measurement numbers I think this thing would work.

 

The difficulty with that idea is that the YICS tool is NOT designed to actually seal the ports, but rather to seal IN-BETWEEN the ports. Trying to seal the actual ports means that:

a) you're going to be cutting the seals all the time, as the drilled port passages are rather sharp edged!

b) the YICS tool then becomes specific for each of the different model engines, as the spacing between the actual ports differs on 550, 650/700/750, 900, and 1100 engines.

c) the more pieces of tubing you use, the less "squeeze" and deformation you'll likely get on each tube, and this may not get the actual sealing that is needed. When the tool is "engaged" (meaning, the rubber seals are squeezed to a slightly larger diameter), it's not the entire seal that swells; much like a tire, it's only the center section that tends to swell, and only in a very short cross-section. When this thin cross section is pressing against a (hopefully) smooth inner chamber wall, then it provides an adequate vacuum barrier; against an actual drilled passage of a certain diameter----and on 550 engines, that passage is going to be wider than that cross section, as 550 engines use rather huge YICS ports----it may not seal quite so well.

 

The remaining issue is finding the high temp hose to use. It appears to be rather difficult to find - at least around here. I gave up and got the tool but even with it you have to be careful how long you leave it in the engine so they don't melt.

Besides the tool is nicely engineered with a flip lever to compress and release the tool. It gets REAL hot - wait till you try to mess with the wingnut to remove it.

The tool is a bit pricey but it was worth it to me.

 

Itsherbike, you will find plans for a tool in my gallery. I built mine off of the picture you are looking at and made my picture a little neater.
If you can swing it, I'd by the $35 one, easy day and you are done.
I'll soldier on with mine until it breaks and I need to replace it.

 

I made one, melted it, and bought one. It doesn't melt if you oil it up beforehand and don't leave it in there for too long. I don't know how long that is because I haven't melted it yet. I'm hoping I don't find out.

 

i made one and i changed the rubber parts 3 times. I lubed mine with oil, then grease, the silicone high temp grease. The rubber gets chewed up after in and out a few times. I bought some high temp tube from a XJ member several weeks ago and have not yet received it!!! I guess he needs the $1.50 more than i did!!!!

 

Could anyone convert those diy tool diameters to millimeters?

 

Just multiply the top number by 25.4 then divide out the bottom number, and you get MM's

5/16 would be 127/16 which is 7.9375 MM

1 1/2 would be 25.4 and 25.4/2 which is 38.1 MM
My tool that Polock gave me has 3 rubbers and no end seal.
apparently the seal closest to the bend seals the passage and a runner.

 

ok, thanks