Both my valve cover gaskets have blown

Joined
Jun 7, 2012
Messages
23
Age
61
Location
Cabot, AR
Bike
1997 ST1100
First of all, my ride is a 97 ST1100 with approx 85,000 miles. I purchased the bike about 6 months ago. Approx 2 months ago, I took the bike into a shop to have my carbs synched and the valves adjusted. I paid for the new valve cover gaskets. About 1 week later, the shop called to pick the bike up, it ran great on the trip home. A few weeks later, I got the dreaded coolant leak under the carbs. I ordered and replaced both water joints along with the gaskets. I decided to change the oil after putting the bike back together, before I took it out for a test ride. Got the oil changed, started it up for a leak check and all was good. I then took it for a test ride in the neighborhood. After driving 1 mile, I heard a whoosh and felt warmness on my right foot. I stopped the bike and saw that it was oil. I nursed the bike home, took off the right covers, and noticed that the rear outter most half moon on the right valve cover gasket had blown. Removed the cover and gasket, and saw that the gasket near the moon was torn, so ordered a new gasket. Cleaned the cover of all the rtv, installed the new gasket. Took it for a test ride the next day. After a few miles, I pull onto the street in my neighborhood and I hear that darn whoosh noise again. This time it was the left valve cover gasket that blew. I remove the cover with gasket, and don't see anything inside that shouldn't be there. I inspect the gasket and sure enough it's torn. So order another one from Bike Bandit, along with an OEM filter. I checked the breather hose and it's not obstructed, nor is the sub air filter. When I changed the oil, I tried a Bosch filter along with Valvoline 10-40 oil. After the first gasket blew, I then changed to a Fram 6017A oil filter and just topped the oil off. So, figured I'd try a Honda filter along with synthetic oil the next time I get it running.
Something I noticed on both valve covers, was that there appeared to be a gold colored hard type glue (maybe Honda goldbond), along with a white colored rtv around the half moons. The shop told me that they didn't have to make any valve adjustments and that the carbs were properly synched. (Get's me wondering if they actually even took my valve covers off).
My question to all you experts out there is, can you advise me of other things to check before I take it for another test ride after I get that second gasket installed. I was thinking of getting a oil pressure gauge along with the necessary attachment and install that to check my oil pressure before actually riding it again. I'm not a compete noob when it comes to motorcycles, just haven't had to do any serious work on one before. I would most appreciate any ideas you guys and gals might have on what the problem could be. I so miss riding her.......Thanks
 
First of all, welcome to the forums. I'm going to leave this in the "Introduction" forum for a while to see if you get a response. Your questions may get missed here so later today if you're not getting any feedback, I'll move it to one of the other sub forums where your chances are better. Good luck getting things back on track. No fun having a great bike that's not up to par.

John
 
I am new here too and I need to know how to go about posting on here.. also need to pick someones brains on the transmission of this bike.
I have an 06 .. and First off how many pounds have people actually ran around with on their ST? not how many does the lawyer say to put on it.. I mean actually run around with? More than 600lbs ? Also Sometime my shift from 1st to 2nd is a bit clunky other times it is smooth, it that common? My Bike only have 9k on it.

:bl11:
 
+1 post it in the 1100 tech section.

If it's anything like the 13 clean that area put some hondabond on the half moon section, don't go nuts with it and reinstall.
But there are a few very knowledgeable 11 folks that don't frequent the intro section that'll see it in the tech section.

Err. oh and welcome to the forum.


Wow OT1 and a jack in 10 minutes :D

Yogi try preloading the shifter with you foot then pulling in the clutch and shifting.

Try the seach function or a site specific google search
"site:www.st-owners.com max weight"
without the quotes

Some find new oil or different brand smooths it out.
PLENTY of threads on that...
 
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Welcome aboard to this great site! Enjoy your ride here!

I would post your questions about the valve covers and other items in the tech section and you will get lots of information from the 1100 experts. Good luck on the repairs.
 
Check to make sure the crank vent hose and the carb drain hoses have not been swapped. If not, then something is obstructing the return path for the oil. The two hoses being swapped can happen... don't ask me how I know. This WILL cause the gaskets to blow.
 
Yes it sounds like you have a crankcase vent issue as Vinny suggests. There should not be enough pressure buildup to blow out the valve cover gaskets. Yes Honda does use sealer around the half - moon seals. I would recommend that you use a good quality flexible sealant in these areas.

Dan
 
I used the permatex red on the right valve cover gasket and she didn't blow on me.
 
I just checked and re-verified that the carb fuel vent is connected to the hose that vents out to the left side of the bike to the rear of the motor and the crank vent hose will be reconnected to the bottom right side of the of the air filter housing after installing the left valve cover gasket
 
Yes it sounds like you have a crankcase vent issue as Vinny suggests. There should not be enough pressure buildup to blow out the valve cover gaskets. Yes Honda does use sealer around the half - moon seals. I would recommend that you use a good quality flexible sealant in these areas.

Dan

+1 The oil pressure would not have anything to do with blowing the cover gaskets, so don't worry about testing that. Given that you seem confident about the vent hoses, check the following: Some shops stuff rags in the oil return galleys to prevent dropping bits into the crank case. If they left them behind, oil would accumulate above the heads and possibly cause this. That return galley should be large and open and rags or towels in there have taken on an oil color by now and may have been shoved down pretty deep so look closely.
 
With me still not knowing what caused the problems, do you guys think I should go ahead and drop my oil pan and have a look see in there?
 
Removing the pan seems a bit extreme. Are you sure no hoses were pinched or assembled incorrectly when you or the shop had things apart? When you describe the gasket blowing with a whooshing sound indicates to me that there is a crankcase vent problem as there should not be a pressure buildup. Something must not be assemble correctly. It seems like too much of a coincidence that this began happening after disassembly.


Dan
 
Removing the pan seems a bit extreme. Are you sure no hoses were pinched or assembled incorrectly when you or the shop had things apart? When you describe the gasket blowing with a whooshing sound indicates to me that there is a crankcase vent problem as there should not be a pressure buildup. Something must not be assemble correctly. It seems like too much of a coincidence that this began happening after disassembly.


Dan

+1000!
 
I know what you mean Dan. I've had those Carbs off a few times before this problem started. There is definitely nothing under the valve covers that shouldn't be there. The breather hose didn't look pinched before I removed it.
When you say crankcase vent problem, is there something other than the breather hose or the sub air filter hoses that I should be checking? You don't think possibly the oil press relief valve?
 
No this should not have anything to do with oil pressure. This sounds like crankcase pressure. For some reason the crankcase is not venting. Plugged hose maybe??
 
Not sure what other hoses to check other that than the crankcase breather hose
 
I am stumped on this one. All I know for sure is that if the crankcase is building up enough pressure to blow out the valvecover gasket - something is up with the crankase breather or hoses.
 
or its generating so much pressure the vent cant bleed it off, run a compression test to verify the compressions staying where it should be, inside the cylinders,

i came across a cbr 250 rr doing the same thing years ago, we spent a long time checking the crankcase breathers before we realised there was a hole in no.3 piston crown,
a blocked jet caused it to get very lean, the gas coming out the vent hose like a compressor line was the first clue there was a major problem.

if its running nicely and giving good compression figures it has to be a blocked vent system
 
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