Cooling system ?, water connection on head

[mlew]

I have the engine out of my 83 VR now and the water outlets on the cylinder head are very rusted and look like they will give me problems in the near future. I want to replace them while they are easy to get to. They are not listed as a part on any Yamaha parts list. Has anyone replaced theirs and where did you get them?

[Condor]

I have the engine out of my 83 VR now and the water outlets on the cylinder head are very rusted and look like they will give me problems in the near future. I want to replace them while they are easy to get to. They are not listed as a part on any Yamaha parts list. Has anyone replaced theirs and where did you get them?

 

Is the scaling internal or external? If internal what does it look like inside the motor.... If it's just the fitting I'd clean it up and use what you have. If the corrosion/scaling is in the motor it might be time to descale it. I don't know if it exists, but maybe an aluminum friendly 'kit' from the auto parts dealer?? The '83's run on the hot side of the temp scale.

[skydoc_17]

Hey Mark,

Those "Coolant Nipples" are pressed into the Cylinder Head at the factory, even if you could buy them as a separate part, the old ones would be a "Bear" to remove. I have had only one 83'VR motor where the nipple was so bad on the rear cylinder that I machined a thin walled Stainless Steel "sleeve" and pressed it into the I.D. of the old nipple to solve a leaking problem. This is why I always use Distilled Water in the coolant system of any VR's I work on. I have also seen JB Weld used to "patch" one of those coolant nipples, it worked, but that fix is not to my liking. Unless the sidewall of the nipple has actually broken thru, you should be OK. For some extra Insurance, use a dab of RTV (don't go crazy with this stuff) around the nipple before you install the Rad. Hose. Another thing to watch for is if the end of the Rad. Hose has rusty metal embedded in it, either trim the hose back to virgin material or replace the hose, you'll be glad you did. Replacing this hose at a later date with the motor in the frame will cause you to pull a few hairs out, I assure you.

A new set of Spring Clamps is also a wise investment seeing as the old ones are 28 years old. The only other option would be to replace the entire Cylinder Head. (With another Cylinder Head that is also 28 years old!)

Good Luck with your Project,

Earl

[mlew]

The nipples have not rusted through yet but they are close. The inside looks normal, its rusting from the outside in. I was hoping I could replace them while the engine is out. I have access to lots of scrap stanless maybe I can come up with a idea from there.

[jasonm.]

The pipe is obviously steel...thus the rust. When I had my engine out. The rust was minimal because they do have an anti-rust plating. What minimal rust was there, I used #600 paper. ALSO do NOT cut the hose back. I have found that instead of getting a new hose. Use laquer thinner and a clean cloth inside the hose, will remove the oxidized and worn rubber. ANd the surface be like new. Just don't over do it. It is removing rubber. Then a slight bit of high quality silicone sealer on the pipe..NOT the hose. Another possibility ...This is steel...maybe a good bit of acid solder in the pitted spots...assuming the aluminum does not suck the heat out before the solder melts.