Oil leak and stripped bolt

If it's broken or just needs tweaked

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Gforce5
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Joined: Thu May 06, 2010 10:22 pm

Re: Oil leak and stripped bolt

Postby Gforce5 » Thu Jun 03, 2010 5:03 pm

Haha yeah I have next to no experience whatsoever. But maybe i'll try it. I didn't understand what to do for a while when i was looking at the clymer manual, but the more i read it the more it looks kind of possible. none of my socket wrenches fit on the ignition cover bolts though, and i don't have the honda valve adjuster wrench. maybe if i find those things. Anyways, I removed the centre breather cover and the two valve adjustment covers, looked around in there to see what the manual was referring to, then put them back on and now a cylinder won't fire!! The bike barely idles and dies easily. It was running great before. what the heck have I done?

Gforce5
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Joined: Thu May 06, 2010 10:22 pm

Re: Oil leak and stripped bolt

Postby Gforce5 » Thu Jun 03, 2010 8:14 pm

My cylinder #4 won't fire now. Bike starts but dies unless given throttle. I started it and made it run for a while and then took out the spark plug and it looks like it's wet with gas. I also tried sparking the plug against the engine block and it sparks. It seams to me like it's sparking and getting gas, so why isn't it firing? Is it flooded maybe? Not sure, need help. Thanks in advance!

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Volker_P
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Re: Oil leak and stripped bolt

Postby Volker_P » Fri Jun 04, 2010 6:03 am

In case you had the plug cables off, first make sure that you did not mix up #3 with #4.
I remember once someone reported he had a blocked valve due to too long bolts or so at an outer valve cover. Possibly you mixed up bolts or forgot washers? That's the only valve cover related running issue that I am aware of at the moment.
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old gringo
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Re: Oil leak and stripped bolt

Postby old gringo » Sat Jun 05, 2010 6:48 am

Valves are pretty straight forward, but these engines are a little complicated to work on if you aren't mechanically savvy. The potential to mess something up is there in some parts of the OHC assembly. Nobody here will fault you if you elect to have someone do the work.
Laissez les bons temps rouler

Gforce5
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Re: Oil leak and stripped bolt

Postby Gforce5 » Sat Jun 05, 2010 10:41 pm

I've checked the plug cables and the bolts and washers and they're all right. Maybe this problem just surfaced and has nothing to do with taking off the valve covers. Any ideas on what this could be?

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Volker_P
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Re: Oil leak and stripped bolt

Postby Volker_P » Sun Jun 06, 2010 11:29 am

As the plug is wet, first try out changing plug and cable with #1 to see if the problem moves with plug or cable. If it does it is obvious what you need to replace. Otherwise carb (jet fallen out?) or compression (valve too tight?). Further issues are possible as well, but that's what I would check first.
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forum links to common technical issues

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diskman
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Re: Oil leak and stripped bolt

Postby diskman » Wed Jun 30, 2010 1:56 am

I just stripped out the same bolt on my '80 CB650 a few days ago after replacing the valve stem seals. I found that the two end bolts must be installed and tightened LAST. After the top cover is installed on about the 3rd "step" in tightening to 7 ft/#s. Also, the bolts don't use enough of the threads. Seems they only bite into about 1/4 inch of the 3/4 inch thread length. I simply moved a slightly longer bolt from the middle area of the cover to the ends and it worked great.

My bike no longer has a smoking habit at stoplights! Whee!

pae
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Re: Oil leak and stripped bolt

Postby pae » Wed Jun 30, 2010 2:17 am

Make sure there's a copper washer there first as that might be all you need *unless the bolt really doesn't tighten up any more in which case you'll need to helicoil or similar)

When I first rebuilt mine I used new stainless bolts and washers, forgetting this bolt needs a copper one, and oil just pumped straight out. Changed it to a copper one and it was fine.

But, if you can't get much torque on that bolt it's probably back to the helicoil option. Try the copper washer first though.

BTW, that's a good idea to try a 1/4" bolt - no harm done of you're expecting to helicoil it anyway but it might save the day.

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Volker_P
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Re: Oil leak and stripped bolt

Postby Volker_P » Wed Jun 30, 2010 3:18 am

Yes, these are the bolts close to the full oil pressure of the camshaft end bearings. That's why you need tight washers there.
I disagree about the proceeding. The outer bolts should be last in the pattern and last torqued in each step. But you should not torque the other twenty bolts stepwise to install the outer ones after that procedure. At least that is how I understood this proposal. No need to apply warp tension.
Of course it is crucial not to mix up bolts of different length. I go that far to say that you should not even mix up any bolts because they fit best and safest into the threads they came out. So I always place them in a geometrical pattern which makes it obvious where they came from (that's my usual procedure with any bolts).
Problems might occur if a previous owner mixed up bolts before, so also this procedure asks for some caution.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

pae
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Re: Oil leak and stripped bolt

Postby pae » Wed Jun 30, 2010 8:46 am

My card template, ready marked out...

Image

And with the bolts in place ready for re-fitting...

Image

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Volker_P
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Re: Oil leak and stripped bolt

Postby Volker_P » Thu Jul 01, 2010 1:23 am

Great idea! :D
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forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

davesee
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Joined: Wed Oct 07, 2009 5:13 am

Re: Oil leak and stripped bolt

Postby davesee » Thu Jul 01, 2010 8:01 pm

haha, i did that same thing this morning with the chart. mine did not look as good.

i faced this exact problem of leaking valve head bolt in the past few days and did indeed solve it with a slightly longer bolt and two copper washers. the new bolt has a 10mm head as well, which seems to help. there is now no leak.

i too found the valves intimidating. i got a 10mm box wrench with offset heads that fits pretty well. that way, along with a screwdriver, you don't really need the valve adjustment tool. i say from experience make sure they are tight. using the feelers, and the effect of the final tightening on the clearance takes a bit of fiddling to figure out, but keep at it.

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Volker_P
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Re: Oil leak and stripped bolt

Postby Volker_P » Fri Jul 02, 2010 1:34 am

I use this one for the valve nuts:
Image
That's more universal than a special tool.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

davesee
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Re: Oil leak and stripped bolt

Postby davesee » Fri Jul 02, 2010 10:10 am

that's what i have exactly.

Gforce5
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Re: Oil leak and stripped bolt

Postby Gforce5 » Fri Jul 02, 2010 1:49 pm

These are some awesome tips. I ended up getting it helicoiled and a mechanic adjusted the valves. Next time, though, i'll maybe do it myself.


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