Pocket Bike Forum - Mini Bikes - Reply to Topic
Thread: B1 Cylinder Head Reply to Thread
Title:
Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:
 

Register Now



In order to be able to post messages on the Pocket Bike Forum - Mini Bikes forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










  Additional Options
Miscellaneous Options

  Topic Review (Newest First)
12-25-2019 05:18 PM
CAM2
Re: B1 Cylinder Head

I use an impact gun..They make ones that work with a hammer....

Hit the nut with heat and WD-40..

For engines like the condition of yours I give the whole engine less coil a good soak in a bucket of diesel fuel for a day....

Like Christi stated it's lefty loosey rightey tightey....
12-25-2019 03:31 PM
EPR
Re: B1 Cylinder Head

They sell stuff for loosening threaded bolts and holes & nuts. Liquid Wrench, etc. If all else fails, you can use a nut splitter, after that get a new nut and clean up the crank threads. The flywheel is on a taper, so its not going to pop off, most have 2 threaded holes and you run 2 bolt thru to the cases and force it off. You can remove the clutch housing and put a socket or..... to hold the crank from turning when you try to take the nut off. I have an air gun and Kawasaki electric wheel nut remover, I keep in my truck/SUV. Make sure its on off and hit it, always works for me.
12-25-2019 03:09 PM
Chrisi
Quote:
Originally Posted by Maird79 View Post
Thanks
Your right the previous owner left the coolant in the system. I havnt been able to split the engine to have a look at everything else because the nut on the magneto/pullstart side isnt loosening, do you know if its reversed thread?
it's a normal thread, you can use a piston stoper or a clutch stoper, heat up the nut will help to loose it.
12-25-2019 02:36 PM
Maird79 Thanks
Your right the previous owner left the coolant in the system. I havnt been able to split the engine to have a look at everything else because the nut on the magneto/pullstart side isnt loosening, do you know if its reversed thread?
12-08-2019 08:27 AM
CAM2
Re: B1 Cylinder Head

Quote:
Originally Posted by Maird79 View Post
Update - the screw secures the dome
Nice...... ...


Ive built a few Blata rep engines for 7-8ft r/c boats and all of the reps I built didn't even have a hole.....

The dome simply pressed-in as you can see from the picture below..

Judging by the oxidation aswell as rust inside that aluminum-magnesium dome that bike will probably need a whole waterpump rebuild with WP shaft and all.....

Good Luck

12-08-2019 07:40 AM
Maird79 Update - the screw secures the dome
12-05-2019 04:57 PM
Maird79 Good idea 👨‍🔧 thanks
Diesel fuel is that just petrol. Or is it actually diesel i would soak it in
12-05-2019 12:01 PM
CAM2
Re: B1 Cylinder Head

Quote:
Originally Posted by Maird79 View Post
Its definitely replica
Where you screw the spark plug in is all one piece its not going to push through. And taking the screw out hasn't released the dome 🤷‍♂️
You have lots of oxidation locking the o-ring inside....soak the dome in diesel fuel for an hour and with a deadblow hammer hit the sparkplug boss and the dome will release....
12-05-2019 10:32 AM
MrKitty probley to bleed air out of the cooling system maybe they failed to get it down into the water jacket those clone engines are known to be extra special...
12-05-2019 07:44 AM
Maird79 Its definitely replica
Where you screw the spark plug in is all one piece its not going to push through. And taking the screw out hasn't released the dome 🤷‍♂️
12-05-2019 06:53 AM
Chrisi
Quote:
Originally Posted by Maird79 View Post
Hello
I pulled out a M4 8mm screw out of the hole in the cylinder head
I thought it would release the dome underneath i think its called, but it doesnt do anything?
Whats the reason for the screw/hole? 🤷‍♂️
That don't look like a Blata head, it looks like a replica head where dome and head are two pieces.
12-05-2019 05:53 AM
Maird79 I should have said because you cant see from the pictures is that the hole is threaded for the first 4mm then threaded for the last 4mm then it has a floor, your reply is totaly right about letting air escape etc. No coolant would be able to escape from the hole even with the screw out. I thought it must be to secure the dome but even with the screw out the dome will not budge it seems its all one piece. To be honest i think this particular engine is an older b1 because ive seen those domes unattached from the head and it shouldnt be difficult to remove but this one seems resilient.
12-05-2019 05:26 AM
Maird79 That makes sense thanks, just made me wonder why mine had this screw and other/new cylinder heads didn't.
12-05-2019 01:53 AM
CAM2
Re: B1 Cylinder Head

Quote:
Originally Posted by Maird79 View Post
Hello
I pulled out a M4 8mm screw out of the hole in the cylinder head
I thought it would release the dome underneath i think its called, but it doesnt do anything?
Whats the reason for the screw/hole? 🤷‍♂️
The dome presses out with a lil WD-40 and some pressure...Theres an o-ring that makes the seal...

The screw on top is used to bleed the trapped air pocket out of the headcap after the radiator is filled .....

You crack the screw fill the rad and when water leaks out instead of air tighten the screw....

Trapped air causes steam..Steam makes a lot of pressure;-more pressure than your head gasket can take and will make it go pop....

Good Luck
12-04-2019 05:11 PM
Maird79
B1 Cylinder Head

Hello
I pulled out a M4 8mm screw out of the hole in the cylinder head
I thought it would release the dome underneath i think its called, but it doesnt do anything?
Whats the reason for the screw/hole? 🤷‍♂️

Posting Rules  
You may not post new threads
You may 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

 
For the best viewing experience please update your browser to Google Chrome