At last, almost two years since I started the engine rebuild it was time to verify if all my posts on the blog were done correctly. So far so good. Final answer will come after the first test run. Getting the license plate next week. Most of the work on the motor was done after I completed the “Man Cave” and the Man Cave was essential for a successful ending. Old and blind I need light and space for such a job. Hopefully this blog can be at inspiration for others working with the same GT 750 issues and pleasures 🙂
Put the kettle on:
Click on the images for detailed view
No decals are used, all hand painted by my nephew Thomas Grenasberg.
According to the information in fig 1 the SRIS tube from the front side should go from the left cylinder inlet ( see the label C in fig.2) to the center cylinder SRIS outlet port. The SRIS type 2 system. Center to Right and Right to Left, all according to fig.6-13 from the manual
From left cylinder inlet
To the Center cylinder SRIS check valve outlet.
Fig.4 shows the two remaining tubes. From Right to Left (red arrow) and Center to Right (yellow arrow ) .
Did the mounting of the cover on the left hand side today. The cover will also house the timing plate, points and capacitors.
I was advised to add some silicone gasket in addition to the new paper gasket, please see the pictures.
Don’t add silicone where I have the yellow marker. I did it wrong and had to wipe it off after the mounting.
Mount the gasket. I had both alignment studs in the cover and therefore I put the gasket as shown.
Add silicone gasket.
To be able to align the side cover in its correct position the pin must hit the hole in the disk rotating the timing camshaft. Be gentle and don’t use force. Rotate a bit to left and right until the cover snap on.
I still had the original screws. Did some polishing on the heads before the mounting.
The difficult job is done, got the cylinder block down onto the pistons without breaking any of the piston rings. Got a helping hand from a friend, was too scared to do it alone.
Hmm, rusty bolts. A new kit has been ordered from UK. The attempt to refurbish the old ones was not a success. Let’s hope I soon get the parts and can mount the cylinder head the next weekend.
Step 1. Remove the thermostat housing
Not an easy task, all of three screws were stuck. Applied some anti rust solvent and went ahead with the job the next day.
The housing were heated up by using a butane torch and in addition I used an impact screwdriver to get the screws loose.
Finally I had the parts separated
Cleaning of the parts using the ultrasonic washer
Step 2, verify the function of the thermostat:
According to the service manual the vale opening temperature is 82 deg C and wide open (8mm) at 95 deg C.
82 deg C and closed
85 deg C and half opened
90 deg C and almost fully opened
Good to go, the thermostat is functioning as specified.
Thermostat response time:
See how it’s closing only seconds after it is out of the boiling water.
Step 3, polishing the thermostat housing:
Nice and shiny 🙂
New parts to be mounted
Step 1: Circlip
Mount one circlip in all three pistons. Move the end position away from the cutout. Be gentle and don’t bend the circlip too much. Use a screw driver as a tool to flip it into the position in the groove. Always new circlips, never reuse old one.
Step 2: Piston rings
Mount the piston ring as shown on the photo. Be aware of the pin locking the ring, see the arrows. You don’t need any special tools for mounting the piston rings. They are quite expensive an if you are afraid of braking any of them, drink a beer before you start 🙂
Step 3: Gasket and O-rings
Mount the gasket, don’t forget to mount three O-rings underneath the gasket.
Before you continue, cover all holes so you don’t drop any parts inside the engine. Can be difficult to retrieve.
Step 4: Pistons
Oil the bearing before and after it’s installed in the rod.
Remeber the washers (31)
Push in the piston pin and mount the last circlip at the end.
Make sure the right piston (label R) is on the right hand side and the arrow is pointing forwards. The left and center piston are identical and are both labeled L