Valve cover leaking from bolt.

mada1594

New Member
Hi guys I am new to motorcycles and working on them. I just got my first bike it is a 1975 cb200t. I am having a problem with oil leaking from the bolts in the valve cover.

I realized there were no crush washers so I put those on there and it helped stop the leak from all the bolts except one. The bolt on the right back closest to you is still leaking from the top of the bolt. Now I did notice that the nuts on the left side when tightened go further down the bolts than the ones on the right. The nuts on the right side when tightened barely sit flush with the bolt.

The leak is not coming from the gasket it is seeping out from the top of the bolt. Like I said I am new to this so please help with any tips and ideas on how to fix this thanks!


Sent from my iPhone using DO THE TON
 

VonYinzer

Over 10,000 Posts
Pull the valve cover, ensure the gasket is ok and re-torque the cover back down according to factory specs.
 

Tim

Administrator
Staff member
There may be a locating dowel missing. Typically valve cover bolts don't need to seal - they pass through sections of the cover that are surrounded by mating surfaces. One might not be, but should perhaps pass through a locating dowel.

Parts diagram? Always start with the manuals.
 

VonYinzer

Over 10,000 Posts
Tim said:
There may be a locating dowel missing. Typically valve cover bolts don't need to seal - they pass through sections of the cover that are surrounded by mating surfaces. One might not be, but should perhaps pass through a locating dowel.

Parts diagram? Always start with the manuals.

That ^^^

Pics may help as well
 

mada1594

New Member
Ok thanks for the tips I will try that! Also I realized that the previous owner installed regular nuts on it and not "cap nuts" that originally came on the bike could this also be the reason the oil is running up through the bolt threads and seeping out the top between the bolt and nut?


Sent from my iPhone using DO THE TON
 

Tim

Administrator
Staff member
Looks like we found the manual a bit ago (uploaded 2011). It's 17MB in size and is the original Honda Service Manual.

www.dotheton.com/downloads/Honda_CB200_CL200_Manual.pdf
 

teazer

Over 10,000 Posts
DTT BOTM WINNER
Oil feed to the top end goes up around the rear outer studs. Cap nuts (dome nuts) and crush washers are essential.
 

Tim

Administrator
Staff member
No mention of washers in the manual. Just 'cap nuts' torqued to 13-16 lb ft. They include the bolt in the tightening pattern as #9 but I wouldn't go past 6-7 lb ft on it. I'm guessing it's a 6mm bolt threaded into aluminum. The nuts go on studs so the higher torque is fine.

Cap nuts and some copper washers for good measure should seal it up.
 

mada1594

New Member
Ok great thanks for the help guys! Ordered the cap nuts and some more crush washers to try this again I will update in a few days if the problem was solved.


Sent from my iPhone using DO THE TON
 

mada1594

New Member
Also I don't have a torque wrench that shows lbs of pressure is there any way to do it without one or do I need to buy one bc idk what 16 lbs ft Feels like.


Sent from my iPhone using DO THE TON
 

VonYinzer

Over 10,000 Posts
mada1594 said:
Also I don't have a torque wrench that shows lbs of pressure is there any way to do it without one or do I need to buy one bc idk what 16 lbs ft Feels like.


Sent from my iPhone using DO THE TON

16 ft/lb = 21 nm or 192 in/lb
 

carnivorous chicken

Over 1,000 Posts
mada1594 said:
Also I don't have a torque wrench that shows lbs of pressure is there any way to do it without one or do I need to buy one bc idk what 16 lbs ft Feels like.

Get a decent torque wrench, you'll need it and there is nothing like overtightening a bolt and stripping threads or breaking stuff that will make you wish you did. Some stuff like rocker adjuster covers is pretty easy -- they don't need to be tightened down that much, and if they weep you can tighten just a bit more or replace the o-ring, but for some stuff you're going to want to know you've done it right.
 

mada1594

New Member
Hey guys another question. I will be getting the crush washers this Monday in the mail. Should I put those on with just the cap nuts or should I put a stainless washer on top of the crush washer?


Sent from my iPhone using DO THE TON
 

J-Rod10

Over 1,000 Posts
DTT BOTM WINNER
Tim said:
There may be a locating dowel missing. Typically valve cover bolts don't need to seal - they pass through sections of the cover that are surrounded by mating surfaces. One might not be, but should perhaps pass through a locating dowel.

Parts diagram? Always start with the manuals.
Not true, in all cases. My 750 DOHC has bolts with tapered rubber on them to seal off. If not torqued properly, oil comes out.
 

teazer

Over 10,000 Posts
DTT BOTM WINNER
No need for a plain washer on top of the crush washer. It's OK to use a smear of gasket goo on both sides of the crush washer just in case...

If that doesn't work, try some stat-O-seals. If they still leak at that point, I would be looking for a blockage in the head that's stopping oil flow into the camshaft.
 

mada1594

New Member
teazer said:
No need for a plain washer on top of the crush washer. It's OK to use a smear of gasket goo on both sides of the crush washer just in case...

If that doesn't work, try some stat-O-seals. If they still leak at that point, I would be looking for a blockage in the head that's stopping oil flow into the camshaft.

Ok great I will keep that in mind thanks for the tip!


Sent from my iPhone using DO THE TON
 

mada1594

New Member
hey guys I got great news put the cap nuts and crush washers on all the studs and they are no longer leaking!

bad news is that now there is a leak coming from the back of the head gasket :( im thinking maybe I should go back in the instructed order and tighten the bolts down again bc I tightened them all down to spec but it seems that some are more loose than others after riding for a bit idk if this is due to the cylinder head flexing or the copper washers maybe still settling in after heating up from the ride???

Also if I am not able to get it fixed by tightening it down again since it is a small leak is it still fine to ride as long as I keep an eye on the oil and clean the engine off so it doesn't get gunky?
 

DTT Bike Of The Month Gallery

DTT Light or Dark

www.jadusmotorcycleparts.com
www.cognitomoto.com
https://www.townmoto.com
www.speedmotoco.com
www.lostapostle.ca/
www.sparckmoto.com
Top Bottom