Maxim X in boxes

I find the exploded parts views helpful:
https://www.yamahapartshouse.com/oemparts/a/yam/500426c5f8700209bc788702/frame

If there is any stud left to weld a nut on, that would be your best option.

Tony

 

Well we don't normally recommend that the side stand relay be thrown away as most here believe it could save your life. Therefore, it is best to remove for troubleshooting and then correct the faults and reinstall.

The starter cutoff relay is a separate relay and is not related to the sidestand relay.

A working neutral switch, diode block, and wiring will enable the starter cutoff relay and the sidestand relay so sometimes it is best to get the bike cranking / running in neutral with a working neutral switch. In neutral bike cranking and no spark would be a good example of pulling the sidestand relay to see if ignition is being disabled because of a faulty relay or wiring.

Note: the diode block is located under the left side cover

Any issues after cranking / running in neutral can then be addressed.

 

Nooo—- disconnect and bypass it temporarily.

 

Exactly!!

 

I do not intend to remove relay for good, only temporarily to exclude kick stand problems. Tomorrow will spend few hours to looking for spark and therefore I do collect all information that can help me. Previous owner claims that the bike was running flawesly before dismantling and that was standing few years like that. So having regard this information I may start looking for a bad corroded connection somehow. Diode block looks for me suspicious, but I have no idea what it does and if that can have any influence on missing spark. I was trying to disconnect the socket from diode but all is so corroded and I can not pull it out because plastic socket cracks and brakes when I do try lift with screwdriver.

 

Thanks, I was suspect the extension tank may be in that place but now I know for sure.

Studs are broken exactly on the sme level as the aluminium head part. So the quetion is if I cn try to weld nut on that without harming head parts. Or, maybe, I can grind alluminum arround the stud to get his 2-3 mm to weld the nut?

 

If the head is still off of the engine:

Option 1 - take it to a machine shop and have them do it

Option 2 - look into the “remove with Alum” discussions

 

Unfortunatelly all is mounted on the frame and engine is fully assebled.

 

Then option #3 -
Pull the engine and take it to a machine shop

 

I do still did not found the spark, have checked allmost everything and nothing. Side stand, clutch, neutral all works. What I did find out is that there is no signal "+" to cut off unit (above carbs), but can not figure out where to looking for. Also there is no signal "-" that switch on starter relay.
Another issue is oil warning light: pulb is ok but no light when turning key on, maybe it has something in common with missing spark.

BTW, oil sensor is beneath in the bottom o sump?

 

Yes, oil sensor is in the bottom of the oil pan.

have you verified all your fuses are good?

you may want to check the pickup coils——If you work the problem from each end, you may find the culprit.

 

That should be a simple check, battery power is routed through the ignition switch, ignition fuse and kill switch and then to the starter cutoff relay. So if you are saying you don't have 12V at the R/W wire on the starter cutoff relay with the ignition set to on then you have an issue with one of the above mentioned, or something as simple as the kill switch is not set to run.

Well the negative won't do much good if you don't have the 12V at the R/W wire. Once again it's a pretty simple process, the R/Y wire of the starter cutoff is grounded through the neutral switch via the diode block or it is grounded though the clutch AND side stand switch.

The oil light should illuminate when the starter switch is depressed, not when the key is switched on. It is routed through the diode block so the diode block needs to be connected and working.

Checking fuses as Hogfiddles suggested is a good idea, hopefully you have already done this??

 

Of course I did checked all fuses on the beginning. But I did finally found the reason...fuses were ok but socket for fuse was corroded, so when I did check fuse all was ok, but did not conduct. So one problem is solved!!!! Thanks you all for a help. Now a lot of other issues that I must face.

 

That was EASY..... you have to give us harder problems than that!!!!

 

Well, be sure more problems will come up. Now i can slightly try to run the engine but all exhaust is rosted thru. It is difficult to repair it.

 

That’s easy, too......
1. Just run it, and wear ear protectors
2. Just get a replacement collector box. Any 85/86 xj700/700x/750/750x collector box will be the same

 

Oil sensor is only for oil level or oil pressure as well? When I do push start button, oil light blink for wille and get off but when change oil it lights. BTW Maxime are intend to consume oil or from change to change?

 

Have a question. Will need to clean and adjust carbs, do not know what I'll see inside the float chamber. The question is how to remove carbs from engine in a most simple way? What do I have to unscrew or remove, already tank is out. I'll check everything but maybe there is something I should pay attention the most?

 

Loosen clamps on both sets of carburetor boots.
Loosen airbox and pull it back (only goes about 1cm or less)
Push airbox boots into the airbox
Remove cables
Rotate/pry/pull carb rack out of the intake boots
Slide rack out to the side to remove

***I HIGHLY recommend removing the airbox chrome trim before doing anything. Otherwise, you KNOW you’re gonna break it. Wrap them in a soft closet and put it waaaaaaaay out of the way are safe.

 

.........and also do the same with the "5valve" trim pieces (if they're still on it).

Also,
The oil light will come on when pushing the starter button. This is for self testing the light and circuit. If it comes on with the engine running it's to warn you the oil level is low. It does not monitor oil pressure, just the level. Use the troubleshooting guide in the manual if you think there's a concern.

The oil pressure can be checked with a manual gauge by adapting a fitting that connects to the upper right side of the cylinder head.

Yamaha engines typically don't consume much between oil changes. You'll only see that if you have a major mechanical concern that will oil foul plugs / cause misfires, and produce blue smoke when running.

Tony