90' SJ questions

[electricgeoff]

I stumbled into a great deal on a SJ but I'm not very familiar with Yamaha. I was looking to trade some of my skis and came across this one for trade. Can I replace the plug wires without replacing the coil and how can I tell what motor it has. It has duel carbs a protec pipe and high compression head so I suspect it is a 701.

 

[Kohldanielzimmer]

Coil wires CAN be replaced but it is a bear of a job. You can buy new Kawi coil (that is compatible) for a reasonable price.

Check the cylinder on the carb side between the carbs. If it's marked 61x it's a 701, top end at least. Post a picture if possible that could tell us a lot.

 

[electricgeoff]

Trying to post pic

 

[X2Kid]

I feel coil wires should be replaced by an expert. You could harm other electrical components if you stuff that part up. There's also the issue of keeping several thousand volts safely under control

I note somebody has substituted a mild steel bolt for the stainless original on the cylinder (exhaust side). You'd want to swap that out for stainless ASAP. You'll be getting corrosion in that location. In a worst case scenario the bolt could snap when loosened if the corrosion progresses too far.

I gain the impression there's been a bit of bodging involved with this 'ski. Give it a solid look over to see if anything else needs attention.

Are those carb's 44's? Would be surprised if somebody put those on a 650. You may have a 701 (at least). Let us know how you go.

 

[electricgeoff]

I noticed the bolt as well and I do intend to replace it. There isn't a 61x on the cylinder that I can see. I thought the same thing about the carbs and a 650

 

[bored&stroked]

Man, that thing is ruff. Bring it back to life!

 

[electricgeoff]

The cooling lines are strange they start off correct manifold in out head. Then in and out of the head pipe and into the tail cone. There is a separate line from the water box to the pisser. It's going into limp mode and I suspect it's because the water isn't flowing through the engine fast enough because all of the water in has to exit through the exhaust.

 

[ub6ib9]

The cooling lines are strange they start off correct manifold in out head. Then in and out of the head pipe and into the tail cone. There is a separate line from the water box to the pisser. It's going into limp mode and I suspect it's because the water isn't flowing through the engine fast enough because all of the water in has to exit through the exhaust.

how hot is the water coming out?

should be hot that you wouldnt want to hold your hand under it for more then a few seconds, but not instantly scald you hot.

does water sizzle on the head/exhaust if you drip it on?

theres a diagram of water line routing somewhere here or maybe google i saw it somewhere


if your plug wires are in rough shape that could be the problem too

 

[ub6ib9]

2nd pic, that plug wire looks like its hanging on by a thread??

 

[electricgeoff]

I was after that plug wire first thinking that it was running on one cylinder but examining it further it's not as bad as it looks. The tape is making it look that way. There is little to no water coming out the pisser which is connected to the water box. My kawis don't have a connection to the w/box

 

[electricgeoff]

It seems to me that the connection to the w/b would be to put water into the box, there is no way water could come out the top of the box to exit the pisser, the box would have to be full to the top.

 

[ub6ib9]

unfortunately i havent done any exhaust upgrades on mine so i can't speak much to that. you should do some reading though heres a few to check out


http://www.x-h2o.com/index.php?threads/pro-tec-pipe-help-running-hot-i-think.93717/

http://www.x-h2o.com/index.php?threads/factory-b-pipe-water-line-recomendations.55337/

http://www.pwctoday.com/showthread.php?t=51281

all i know is that usually the pisser should be T'd coming from the line that feeds into the head, if you dont have water there its more serious then not in the exhaust, see what the other guys say here but either way i would put one in at the head just for peace of mind. Mine dumps warm water right on my feet its nice for the colder water i ride in, and i can make sure its not over heating.

There is also the possibility you have a blockage in one of the lines, at the very least you can start disconnecting things one at a time, blowing through it, visually inspecting for anything inside it etc, especially on a new ski its good to check everything out.


Good luck