Register Community Calendar Today's Posts Search

Go Back   GZ 250 Forums > GZ250-Specific > Troubleshooting

Reply
 
Thread Tools Display Modes
Old 09-03-2015, 01:00 AM   #1
chandlerbingfl
Senior Member
 
Join Date: Apr 2010
Location: Florida
Posts: 142
Gasket in between head and cylinder?

I think my lack of power is because I have a leak in the above mentioned area. My mech pointed out a stud missing a nut, he tried to replace but the stud appears to be stripped.

I guess what I'm asking is... Any idea of cost to place? Just looking for a ballpark estimate.. Even ballpark hours to do the job would help me decide whether to replace or look for something else..

TIA,
chandlerbingfl



Login or Register to Remove Ads
chandlerbingfl is offline  
Reply With Quote
Old 09-03-2015, 07:21 AM   #2
spldart
Senior Member
 
spldart's Avatar
 
Join Date: May 2015
Location: Stafford, Texas
Posts: 604
I'm gonna preface my advice with the disclaimer:
I am not a certified mechanic but I've rebuilt a number of failed motors and repaired many more
bikes.
This advice is a guess site unseen.

If you and your mechanic think the lack of power is a compression area leak due to a blown
head gasket then you should know that once that metallic ring of the head gasket gets
breached the gasket extremely quickly degrades to the point the motor simply wont run.
Especially on an air cooled motor.
I'm talking single to double digit miles.
Now if you do have a leak that has lasted for many miles then valves and rings are suspect
as they can handle leaking for more miles.

You need to do a compression test.
Once just cold.
If under 100 psi then time for a second....
through the spark plug hole you will oil the piston rings.
I try to take a straw. dip full of motor oil, then go in the combustion chamber at the back
of the piston and cyl wall and let it drain the oil. Put the tester back on and check.
If the compression test goes up substantially then your rings are your problem.
If not then gasket, valves or a crack in piston or head.

ps: some peeps just get a can of spray oil and coat the hell outta everying using the little
red straw for the second compression test.

Now the missing nut stud. Its the one where the stud comes down and a nut goes up on
it right? I had one of those missing for a few thousand miles before I found out and replaced
it.
Stripped stud..... Bummer. That is an open the motor kind of issue.
First try to determine compression dry and wet though.

A shadetree mechanic with experience can do a head gasket in an afternoon.
A shop is gonna charge a substantial chunk of change no matter what.
Whenever they open a motor they do.
Like 35 to 50 bux an hour. A few hours. plus parts.

that's my best guess.

Last edited by spldart; 09-03-2015 at 07:23 AM.
spldart is offline  
Reply With Quote
Old 09-04-2015, 12:30 AM   #3
chandlerbingfl
Senior Member
 
Join Date: Apr 2010
Location: Florida
Posts: 142
Quote:
Originally Posted by spldart View Post
I'm gonna preface my advice with the disclaimer:
I am not a certified mechanic but I've rebuilt a number of failed motors and repaired many more
bikes.
This advice is a guess site unseen.

If you and your mechanic think the lack of power is a compression area leak due to a blown
head gasket then you should know that once that metallic ring of the head gasket gets
breached the gasket extremely quickly degrades to the point the motor simply wont run.
Especially on an air cooled motor.
I'm talking single to double digit miles.
Now if you do have a leak that has lasted for many miles then valves and rings are suspect
as they can handle leaking for more miles.

You need to do a compression test.
Once just cold.
If under 100 psi then time for a second....
through the spark plug hole you will oil the piston rings.
I try to take a straw. dip full of motor oil, then go in the combustion chamber at the back
of the piston and cyl wall and let it drain the oil. Put the tester back on and check.
If the compression test goes up substantially then your rings are your problem.
If not then gasket, valves or a crack in piston or head.

ps: some peeps just get a can of spray oil and coat the hell outta everying using the little
red straw for the second compression test.

Now the missing nut stud. Its the one where the stud comes down and a nut goes up on
it right? I had one of those missing for a few thousand miles before I found out and replaced
it.
Stripped stud..... Bummer. That is an open the motor kind of issue.
First try to determine compression dry and wet though.

A shadetree mechanic with experience can do a head gasket in an afternoon.
A shop is gonna charge a substantial chunk of change no matter what.
Whenever they open a motor they do.
Like 35 to 50 bux an hour. A few hours. plus parts.

that's my best guess.
Best guess? Everything you said is viable, gives me more things to look for. Hard to type with one finger but I fractured my elbow after a nasty, dumb in a way washout in gravel while turning right.

Thank you for the info!
chandlerbingfl



Login or Register to Remove Ads
chandlerbingfl is offline  
Reply With Quote
Reply




Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:08 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.