Removing GT750 cylinder barrels

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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

Drewski wrote:
Suzukidave wrote:As many GT fans there are in the UK i cannot see where one couldnt be borrowed ?
There should be one available for loan once I've got mine together. I can't believe the problems I had trying to find those bolts online today, got there in the end but I've had to go with 1.5 pitch rather than 1.25.
Are you talking about the pusher bolts or the hold down bolts ?
the older i get the faster i was
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

The pusher-down bolts. I could find them long enough, strong enough, with full length thread and the right pitch.........but not all four together :!: :D
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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

The pitch on the pusher bolts isnt that critical so use what you can find .
the older i get the faster i was
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

Suzukidave wrote:The pitch on the pusher bolts isnt that critical so use what you can find .
Roger :up:
Pusher bolts sourced, and I can get them machined at the ends to fit onto the cylinder studs......steel plate next.
Spent the afternoon geting the engine stripped down ready to remove and the cylinder bolts have been sitting in a deadly mix of Acetone, Rust Eater and WD40 all week.

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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

Have you tried at all to see if the cylinder will come loose without a puller plate ? If your engine was one that came from the factory with the sealing washers on the head bolts you may be lucky that the block will move with a block of wood and a sledge hammer . The block is very strong around the exhaust ports so can be hit on pretty good without damage , just take care of the exhaust studs or best if you could remove the studs first .
the older i get the faster i was
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

I havn't given it much "hammer"...mainly because I can't get in to give it a swing. Presumedly the "block of wood and sledge" routine is with the engine out ja?
I've poked down by the side of some of studs to get an idea of condition and with about 4, (the back ones suffice to say), I can get right down. I'm not sure how scientific this is or if it has any relavence to how easily they'll split but it seemed quite good news. The single stud for the head came right out too.
Head gasket was the worst I've ever done :x Blown head gasket has rusted everything in the vicinity, anything near that was stuck solid.
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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

It would be a challenge to get at the engine block with the bike standing . If you could lay the bike over on its side in the yard with something soft under it you ( and a helper ) could get a good swing at it . Disclaimer .. please be careful if trying :shock:
the older i get the faster i was
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

OK...finally cobbled a puller together, I've got 3 sets of pusher bolts to go with it- 70mm for cracking the block, 120mm for stuborn examples and 150mm for blocks that fight you all the way.

If anyone on here can use it, just PM me and I can post it on. I'll post it anywhere at the users cost but obviously post to the States and Oz will cost a small fortune :( If your anywhere near B'ham or Cambridge UK I can drop it off or your welcome to collect.

I'm going to give it a test run as soon as I get my engine out and on the deck. Total cost was about £30GBP, just under $50 US...............although I did treat myself to a new tap and wrench for another 30 knicker :ssh:

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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

That looks like it will do the job for sure , nice thick piece of steel :up:
the older i get the faster i was
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

Nearly sliced the end of my thumb off with it when sticking it in the car too :oops: I'm tempted to try it now but the bike's in my Dads garage and I'm not sure his neighbours would appreciate me hammering at 10 PM :D
Drewski
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Re: Removing GT750 cylinder barrels

Post by Drewski »

Houston....................we have seperation 8) :lol:

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You wre right, I didn't really need it. I'm not sure how much of that was down to soaking the studs for about a fortnight but getting the block off in the frame gives me a better chance off lifting the rest of the motor out on my own.

Big thanks to OP and the forum for the description etc :up:

I did get a couple of M8 holes slightly out....my fault for not taking enough time marking them out..... but re-drilling them slightly bigger sorted that out.

Seperation revealed what looks like a serious blowby problem :D

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And maybe a partial seizure?
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aslsmm
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Re: Removing GT750 cylinder barrels

Post by aslsmm »

Guys I've been working with this for a month now and can't seem to get it. I'm using all thread cut into 7 bars and nuts to create the pressure studs. I'm also using a extra head I have instead of a puller plate. The right side of the barrels has released, but the left side is stuck. I've removed the studs and hammered in the hole thats still stuck but no luck. It's an early 73 motor, had anyone else encountered this?
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Suzukidave
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Re: Removing GT750 cylinder barrels

Post by Suzukidave »

Oh yeah ... no two come off the same , you really need the block to lift the same on both sides as if it get cocked on the studs it can really get stuck . If you didnt try heat do that , its a lot of mass to get heated up but if you can it could help .
the older i get the faster i was
blakenator
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Re: Removing GT750 cylinder barrels

Post by blakenator »

they are a pain to get off, I had one stud that was seized but everything else was free. I just had to keep pulling up until it was free, you have to pull it quite far
dnaj11
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Re: Removing GT750 cylinder barrels

Post by dnaj11 »

I've got one that's gonna be hard. Got this 71 kettle and it came with the head off, otherwise complete and with a title. On closer inspection, two of the smaller head bolts are broken off in the cylinder. Two of the other smaller bolt holes are stripped, one with half a heli-coil sticking out, the other with a full heli-coil installed. The cylinder is partially raised on the right side but nearly (not completely though) flush on the left side. The right side has visible pry marks at the base. I'm guessing they went to work on something and broke the smaller head bolts, then couldn't get the cylinder off and may have stripped the remaining bolt holes. I've got everything soaking in PB blast. I'm very intrigued by the hammer drill technique. I've got an air hammer. Might I grind down one of the bits to flat and dull and try it. Can't really use the puller technique because half the holes to hold the plate are stripped or broken.
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