Jump to content
Sign in to follow this  

Engine blowing from cylinder cover gasket

Recommended Posts

Hi guys, I'm new to the forum so i think it's etiquette to introduce myself.

 

My name is Martin and I'm from Buenos Aires, Argentina. I'm the proud father... i mean owner of a '92 xr600r.

 

I've had the bike for a couple of years (after owning a couple of bikes before it) and i absolutely love it. But as any old bike, i has it's coughs and hiccups every one in a while.

 

The latest started a few weeks after rebuilding the engine (not me but the local mechanic). At first it was only noticeable at high revs. A valve adjust seem to solve it but it came back. I'm talking of a sound when accelerating the bike that sounded like a perforated exhaust. The bike stood for a few months because of other repairs, but when i started riding it again the sound not only came back but it became more noticeable and could be heard at low revs as well.

 

Long story short, i took it to the mechanic and he says it looks like the cylinder cover gasket is leaking, probably due to a stripped thread on the cover. He recommended doing inserts but the quote is quite steep.

 

So here's the questions. I'm thinking of doing this myself. Not the actual inserts, but all the taking the engine apart and putting it back together. I have done some work on the bike and on some of my previous bikes, but messing with the engine seem a bit more complex to me. Do you think this is something that i could do at home myself? 

 

Thanks in advance for any help or tips and I'm glad to be joining these forums.

Share this post


Link to post
Share on other sites

Installing inserts is something you can do at home. You can go heli-coil or Time-Sert. I have not spent any time Argentina (West coast of South America only) but I would think Heli-Coil is available in your locality.

I've installed these at home in the same location as you will need with nothing more than a drill, bits, and some red loctite...

Share this post


Link to post
Share on other sites

Installing inserts is something you can do at home. You can go heli-coil or Time-Sert. I have not spent any time Argentina (West coast of South America only) but I would think Heli-Coil is available in your locality.

I've installed these at home in the same location as you will need with nothing more than a drill, bits, and some red loctite...

 

Thanks condershire, i appreciate the tip about the inserts. But it's the taking apart and putting the engine back together that worries me. Maybe it's that i've never done it (i'm lying actually, i tried to put new gasket on a 50cc piece of crap when i was 15 and i only made it worse) and it looks more difficult than it really us, but i would hate to mess it up.

Share this post


Link to post
Share on other sites

Thanks condershire, i appreciate the tip about the inserts. But it's the taking apart and putting the engine back together that worries me. Maybe it's that i've never done it (i'm lying actually, i tried to put new gasket on a 50cc piece of crap when i was 15 and i only made it worse) and it looks more difficult than it really us, but i would hate to mess it up.

confidence, everyone has some hesitation. get a book, go slow and methodically and take pictures as you go. remember that someones hands put it together, yours can take it apart and back together. just like a recipe, if you follow the directions, it will come out finished the way its intended.

  • Like 2

Share this post


Link to post
Share on other sites

It sounds like you have a blown head gasket, not a valve cover gasket. I just did a rebuild on mine over the winter for the same problem. Mine ran OK... the reason I knew it was leaking compression was it would blow bubbles out the joint between the cylinder and the head when I started it up after washing it. Soapy water will tell you if you have a leak.

  • Like 1

Share this post


Link to post
Share on other sites

It sounds like you have a blown head gasket, not a valve cover gasket. I just did a rebuild on mine over the winter for the same problem. Mine ran OK... the reason I knew it was leaking compression was it would blow bubbles out the joint between the cylinder and the head when I started it up after washing it. Soapy water will tell you if you have a leak.

 

Right now i'm midway in the engine disassembly. I have drainded the oil and going back seems more work to keep going. I did see oil perspiration on the cylinder cover gasket and that's my main suspect. But i guess i won't know until i have removed the engine and examined the threads to see if any is worn or stripped.

 

I'll keep an eye to see if the valve cover gasket looks bad. Thanks a lot guys!

Share this post


Link to post
Share on other sites

Post a few pictures of the cylinder head to bore surface areas when you get that far in. People here are pretty good at being able

to eyeball and id the leak area just by looking at the gasket between the two surfaces..ie,,.pop a couple of shots of both sides of the gasket

and post them if you can..Then remove the gasket and post a few shots of both metal sufaces..head side,,and bore side..

Edited by Horri

Share this post


Link to post
Share on other sites

If the head gasket is the culprit, you will see carbon tracks where it has been leaking. What you describe cannot really be the valve cover as there is no compression under the valve cover (unless your rings are shot). If you hear what sounds like an exhaust leak, it is not likely caused by a valve cover leak. If you had an XR650L, it could also be leaking from the front of the head where the smog apparatus connects... you have an XR600 though so that should not be a concern.

 

My head gasket was blown and there were no stripped bolts, bad threads or warped parts... just a bad gasket. Don't assume that you have a problem until you get into it and see.

Share this post


Link to post
Share on other sites

It sounds like you have a blown head gasket, not a valve cover gasket. I just did a rebuild on mine over the winter for the same problem. Mine ran OK... the reason I knew it was leaking compression was it would blow bubbles out the joint between the cylinder and the head when I started it up after washing it. Soapy water will tell you if you have a leak.

I like this advice. I am going to try it myself next time i fire the pig up. How common is a leaking/blown head gasket on the xr600r-xr650l air cooled mill ThumpNRed.....especially if it has been driven hard?

Share this post


Link to post
Share on other sites

Not sure how common it is, but mine was likely a product of flogging the crap out of it and getting it really hot, splashing through a creek... (really hot with rapid cool down).. you know the drill... trail rides in August :ride:

Having said that... you may be next in line :devil:  A spray bottle of soapy water will tell the tale.

 

I like this advice. I am going to try it myself next time i fire the pig up. How common is a leaking/blown head gasket on the xr600r-xr650l air cooled mill ThumpNRed.....especially if it has been driven hard?

Share this post


Link to post
Share on other sites

Not sure how common it is, but mine was likely a product of flogging the crap out of it and getting it really hot, splashing through a creek... (really hot with rapid cool down).. you know the drill... trail rides in August :ride:

Having said that... you may be next in line :devil:  A spray bottle of soapy water will tell the tale.

Yikes...! So im guessing comming out of the woods and driving into a car wash, shutting the bike off and taking the high pressure hose to the pig might not be such a good idea neither.

Share this post


Link to post
Share on other sites

Post a few pictures of the cylinder head to bore surface areas when you get that far in. People here are pretty good at being able

to eyeball and id the leak area just by looking at the gasket between the two surfaces..ie,,.pop a couple of shots of both sides of the gasket

and post them if you can..Then remove the gasket and post a few shots of both metal sufaces..head side,,and bore side..

 

Thanks a lot guys, really! It is very helpful and encouraging to receive so much advice and knowing i can come back here when i'm stuck. I haven't had time these days to move forward but i can't wait to do so. 

 

I don't know if it helps but here are a couple of videos of the bike running cold and hot. The "punctured exhaust head" sound is not noticeable (or doesn't appear) when i'm not riding. I'm guessing that's because the engine only blows when it has to exercise force.

 

Bike cold: 

Bike hot: 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×