Rocker cover BROKE...Valve spaceing WAY off need help.

[brownv1]

So was checking the valve spacing today cause I had the bike pretty much bare so I figured why not(regret soooooo much). Broke the inspection cap (screw cast aluminum). The ones from the 650's don't look like they fit so I found a place that lists OEM replacements for the 400's. My question is what is the difference in the plugs from the SH model and H,J, other models. The other models are half the price but look the same. Any thoughts?

So after reading all the guides on here I felt compitent in doing a valve check and found my problem or one of them. Bike hasn't run right yet so I'm checking all the boxes. When draining the oil I feel like I smelled gas and since the last time I ran the bike there is GUNK(I believe oil) spilled back into my carbs. My rockers never seem to come out of contact with the valve so clearly I need to adjust. I was wondering if this is my main culprit for the mystery fluids. I'm not a genius at this stuff but I believe that all the valves are remaining slightly open which would account for the oil in the carb, leaking back since the intake valve is staying somewhat open all the time. What gives with the fuel smell in the oil. I have done a compression check got 170, 168 so I assume the rings are fine any ideas? Could I be right about the gunk in the carbs?

 

[Shaun Chandler]

why don't you measure across the outside of the threads and then check the thread pitch with a thread gauge anyone with that model could quickly do the same and tell you if they area a match. If you like I could measure the threads on mine. I have a 78 xs400 sohc and an 80 sohc.

Any volunteers? I know mine likely won't be a match cause its an xs400e but I can check and post the results up here

Shaun

 

[Shaun Chandler]

alright I measured across the major diameter (tip of thread to oppsite tip of thread) of the thread and its 31.86 millimeter with a 1.5 pitch. That makes it a M32* 1.5 pitch. And I check both my 78 and my 80 (mabey 81 can't remember) they are both the same. Hopefully that helps you to cross reference.

Shaun

 

[xschris]

If you need one I have of bunch of these things if you need one I can sell you one cheap

 

[brownv1]

Shaun I got the same measurement, as close as I can get I'm using a tape. Are yours aluminum the only reason I can figure they have a price diff would be for diff material but I'm assuming they are all made of aluminum.

Chris I need two and would be interested how much to get two of them to Georgia?

 

[xschris]

How about $9.00 shipped for two.

 

[brownv1]

Sounds good I'll pm you and we can set it up

Besides the valve's I think I figured it out. Floats prob wrong height so gas keeps flowing and eventually flowed into the crank breather and for the gunk I figure its half burned coming back through the open valves.

I'll get these covers get her buttoned up and let everyone know for future references.

 

[Shaun Chandler]

ya you may be able to get them in aluminum and chromed steel. Either way nine bucks for two sounds like a great deal and a problem solved.

Shaun

 

[bcware]

By the way, Chris, I need one of those caps too for my '78. I mangled one pulling it off with vice grips. The PO rounded off the head!

 

[xschris]

Pm sent

 

[vfost]

Just a note on your valves mabye i am misunderstanding what you're saying but i dont think having them adjusted to tight would cause oil to get into your carbs. I'm just not sure the route it would take to even get there unless your rings were bad letting it get into the cylinders. Also i had my valves adjusted to tight once as well and the bike simply would not start. Even worse when it did try it would shoot a ball of flame right out the back of the carbs because the valve was not shutting completeley letting it trace the fuel back into the carbs.

 

[drewpy]

don't forget to use copper grease on the threads, or you'll not come unstuck again!

 

[lhaolpa]

So was checking the valve spacing today cause I had the bike pretty much bare so I figured why not(regret soooooo much). Broke the inspection cap (screw cast aluminum). The ones from the 650's don't look like they fit so I found a place that lists OEM replacements for the 400's. My question is what is the difference in the plugs from the SH model and H,J, other models. The other models are half the price but look the same. Any thoughts?

So after reading all the guides on here I felt compitent in doing a valve check and found my problem or one of them. Bike hasn't run right yet so I'm checking all the boxes. When draining the oil I feel like I smelled gas and since the last time I ran the bike there is GUNK(I believe oil) spilled back into my carbs. My rockers never seem to come out of contact with the valve so clearly I need to adjust. I was wondering if this is my main culprit for the mystery fluids. I'm not a genius at this stuff but I believe that all the valves are remaining slightly open which would account for the oil in the carb, leaking back since the intake valve is staying somewhat open all the time. What gives with the fuel smell in the oil. I have done a compression check got 170, 168 so I assume the rings are fine any ideas? Could I be right about the gunk in the carbs?

If your valves were not closing,you wouldn't have that much compression,and the exhaust valves would quickly burn. Also,it would help to know what model you have. lha

 

[lhaolpa]

By "valve spacing",I hope you mean valve lash,or tappet clearance.I've never heard it called that,but then again,I've not been everywhere. lha