Blocky deck fix

docs

Member (SA)
Jun 26, 2010
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Hi all, after having an issue with a blocky deck and resolving it I thought I would share it as it may be a common issue.

The heads were not raising far enough and allowing the tyre wheel to engage the take up spool and thus playing a tape. After investigating whether it was being caused by the deck head spring issue I could see that this issue was indeed present but was not the reason for the heads not raising, so one thing at a time, lets get the heads being able to move far enough up first.

After investigating the deck a bit and taking the back plate off along with fiddling and trying to raise the heads manually, I could see there was a piece which was stopping the heads raise any further.

The front plate must be removed to see the deck front.

The photo below shows the take up spool and tyre which engages it inside the red circle and the problem causing the heads to stop short.
deck1.jpg

Below is a look at how the take-up spool is engaged by the heads raising and the small lever above the yellow arrow dropping into the narrower gap on the head plate beneath the red arrow as it moves upwards. When the lever moves into the space the tyre engages the take-up spool and makes it turn.
deck1.5.jpg

A closer look at the little notch which seems to be resetting after manually moving the gears and flywheel. This is where it should be resetting to but as you can see in the picture above that it is resetting too low.
deck2.jpg

Looking at the reverse of the deck and carefully removing the security plate for the flywheel and the flywheel itself, you can see the lever which is related to that little notch on the front. At this stage you can determine that it is related to the pause function. This lever lowers the notch on the front and subsequently lowers the head plate. Trying to manually move it was difficult because it was stiff as hell.
deck3.jpg

Removing the shoe clip on top and sliding the lever off revealed a pretty dirty and grim looking pivot post,
deck4.jpg

I basically cleaned that post and inside the hole on the lever to provide a smoother contact, put it back together and tested manually that the lever would be easier to move and it was.

if you have this issue, don't automatically assume that it is related to the head spring issue (which can be read here - https://boomboxery.com/forum/index.php/topic/13086-ge-3-5259a-blockbuster-play-not-engaging-ff-rw-pause-fine/ )

Incidentally, the pause button and mechanism worked fine, its just that the lever behind the button stays in the on position and doesn't reset when pause is taken off again.

Hope this might help others fixing their blocky decks.
 

T-STER

Member (SA)
Jul 14, 2014
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Cracking fix Dave and so useful you documented it with pics. I have a blocky so it's good to know what to do if this issue crops up. How do you like your blocky?
 

Hisrudeness

Member (SA)
Jan 1, 2014
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Thanks for this Dave. This will help as a reference point for people. I assume this applies to the similar box with the long strip leds? Ive forgotten the model? Anyone?
 

BoomboxLover48

Member (SA)
Dec 3, 2010
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Great information shared there Dave!

I've had the same issues with Akai auto reverse decks. Posts were pretty much frozen and was stuck. So, auto reverse will not engage at all. It was AKAI GX F66 R deck that had this issue. After I knew this issue I always check the posts.
 

randyjohnson1

Member (SA)
Dec 31, 2018
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My girlfriend got me a "blockbuster" for Christmas The tape deck was messed up so bad that I couldn't even shut the door with a tape inside and it also had the problem described in this tutorial. I did the repair above and was able to listen to a tape - it played nicely. It still struggles with FF and Rev, but one thing at a time. Thanks for the great tutorial - wouldn't have solved it without all those great pictures! BTW, new to the forum today!!
Can anyone list the 3 belt part numbers? I've seen different notes with different belt numbers referenced. I have SCQ8.2 pretty much identified but I'm uncertain what the other 2 are. Thanks for the great article!!!!!
 

docs

Member (SA)
Jun 26, 2010
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Thrilled that this has helped.
Regarding ff/rew, make sure you give the tires a clean (which usually engage the flywheel though I can’t remember how they engage on this deck) as these are what slip when ff/rew is not too strong.
 

randyjohnson1

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Dec 31, 2018
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docs said:
Thrilled that this has helped.
Regarding ff/rew, make sure you give the tires a clean (which usually engage the flywheel though I can’t remember how they engage on this deck) as these are what slip when ff/rew is not too strong.
Thanks for the advice! I'll give it a try when I figure out the belts and install them.
 

randyjohnson1

Member (SA)
Dec 31, 2018
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Update - I had to really tear into this thing to get it to work perfectly - but - mission accomplished. New belts are installed, but the problem listed above was discovered in several areas. Apparently, the original lube used where a part pivots or rotates on a metal post dries and causes the part to not move or move with difficulty. I had to remove all of these pieces, clean the posts with alcohol, and use pipe cleaners with alcohol to clean out the holes that mate with the posts. Also, in the fourth picture of this tutorial above (to the right of the image) is a plastic gear that requires lube on top where a another pivoting plastic piece slides. Even though the lube felt fresh, I had to clean and re-lube the surfaces to get the play and stop functions to complete their cycles. By watching and testing the tape unit while it was out of the case, I was able to focus in on the pieces not working. This tutorial was incredibly helpful - I don't think I would have figured this out, otherwise.

GE Blockbuster.jpeg

Here's a pic.


Not sure why it is upside-down
 

caution

Member (SA)
Mar 25, 2014
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Boomboxery
View attachment 42442
I basically cleaned that post and inside the hole on the lever to provide a smoother contact, put it back together and tested manually that the lever would be easier to move and it was.
I had the same issue, but after cleaning the lever's hole and the shaft, it was still stiff. The plastic shrunk, so I had to lightly bore it out before it began to move freely again.
 
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Pothoel

New Member
Jan 25, 2022
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Idaho
Great info here! My SCR-8 deck will stick intermittently in the play position, thus not allowing the tape to be removed. Manually turning the internals will release it, so it sounds like some sticky parts are the problem. I've been able to re-create the issue with the deck sitting out of the box and can see where it appears something is just not releasing due to the dirt and grime mentioned above. Time to dive in for a good cleaning.