The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 09-18-2014, 06:58 PM   #1
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
broken trans modulator bolt

anyone ever have any luck removing a broken bolt on the transmission modulator clamp or come up with an alternative way to keep it in ? it's on a 1979 suburban 4x4 I just bought, and there is no way I'm getting in there with a drill.
Attached Images
 
carnut4real is offline   Reply With Quote
Old 09-18-2014, 07:58 PM   #2
bob_o
Registered User
 
bob_o's Avatar
 
Join Date: Jan 2012
Location: Arizona Bay
Posts: 145
Re: broken trans modulator bolt

What about an Easy-Out and a stubby tap handle or small crescent wrench?
__________________
1975 GMC Sierra - Electric Funeral

1962 Buick LeSabre - Mr. Krinkle
bob_o is offline   Reply With Quote
Old 09-18-2014, 08:41 PM   #3
SkinnyG
Registered User
 
SkinnyG's Avatar
 
Join Date: Feb 2012
Location: Beautiful BC, Canada, eh?!
Posts: 2,246
Re: broken trans modulator bolt

Try merely rotating it out by tapping it with a punch and a hammer.

Unless the bolt was the wrong one and was sheared off after it bottomed in the hole, it should be loose enough to persuade out.
__________________
1961 Apache: "Grabber Orange" Shortboxed, pancake, step-notch, air-ride, boosted-LS
1977 Silverado: Shortboxed & dropped, potato-potato
V8 Pontiac Firefly (Chevy Sprint): The ultimate engine swap: 5.7L in a 1.0L bag
Lotus Super 7 Replica: Scratch-built street-legal rollerskate
SkinnyG is offline   Reply With Quote
Old 09-18-2014, 08:49 PM   #4
Just call me Sean
Registered User
 
Just call me Sean's Avatar
 
Join Date: Jun 2014
Location: Orlando Florida
Posts: 1,598
Re: broken trans modulator bolt

Aluminum transmission housing and steel bolt, it might be seized in there. Sure it sucks, but you may have to pull the transmission.
__________________
Quote:
Originally Posted by Early Cuyler
Fights begin, fingerprints are took, days is lost, bail is made, court dates are ignored, cycle is repeated.
Just call me Sean is offline   Reply With Quote
Old 09-18-2014, 09:13 PM   #5
Rascal_one2001
Registered User
 
Rascal_one2001's Avatar
 
Join Date: Dec 2006
Location: North Carolina
Posts: 308
Re: broken trans modulator bolt

If it's a th350 worst case you have to pull the transfer case to get clearance to drill it. If it's a th400 you should be able to unbolt front drive shaft and the cross member and lower the Trans enough to clear to drill just don't break your distributor. Or if the bolt is broken flush you can put a 5/16 nut over the broken bolt and weld the center so it welds to the damaged bolt and then the heat will help break it free.
__________________
1985 1500 454, 4l80e, 12 bolt, 5/6 drop, 20s
Rascal_one2001 is offline   Reply With Quote
Old 09-18-2014, 11:34 PM   #6
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

What's with everybody who wants to pull the tranny, or tear it apart or drill out the bolt that's impossible to get at.
Get creative and build a simple bracket to replace the one there. Use existing bolts on the pan or the bell.
geezer#99 is online now   Reply With Quote
Old 09-19-2014, 01:04 AM   #7
Just call me Sean
Registered User
 
Just call me Sean's Avatar
 
Join Date: Jun 2014
Location: Orlando Florida
Posts: 1,598
Re: broken trans modulator bolt

Just use duct tape.
__________________
Quote:
Originally Posted by Early Cuyler
Fights begin, fingerprints are took, days is lost, bail is made, court dates are ignored, cycle is repeated.
Just call me Sean is offline   Reply With Quote
Old 09-25-2014, 08:08 PM   #8
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

I ended up fabricating an alternative way to fasten, but I changed the modulator valve, fluid and filter, and the transmission is still shifting at really high rpms ?
carnut4real is offline   Reply With Quote
Old 09-25-2014, 08:08 PM   #9
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

I have good vacuum also
carnut4real is offline   Reply With Quote
Old 09-25-2014, 09:51 PM   #10
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

So, just adjust the modulator!
A small flat head screwdriver will work.
geezer#99 is online now   Reply With Quote
Old 09-25-2014, 09:55 PM   #11
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

I'll give it a shot. I figured it would preset
carnut4real is offline   Reply With Quote
Old 09-25-2014, 10:01 PM   #12
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

It's acting the same as it did before Changed it could it be the governor
carnut4real is offline   Reply With Quote
Old 09-25-2014, 11:38 PM   #13
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

Late shifting or early shifting is usually modulator.
They aren't pre-set.
Be aggressive in your adjustments. Don't go just one turn at a time.
IIRC turning it out is the way to go.
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 01:26 PM   #14
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

Geezer thanks for the info, let me ask you this, is the fluid suppose to run out when the modulator is removed ? I've turned it out multiple turns with no results, but thought I had read somewhere that there shouldn't be much fluid behind it ?
Thanks
carnut4real is offline   Reply With Quote
Old 09-27-2014, 01:56 PM   #15
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

Yes! A little fluid comes out when you remove it.
Did you make sure the pin was put back in when you installed the new one?
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 01:58 PM   #16
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

I can feel the pin in there, and I never did remove it, but the fluid is running out
carnut4real is offline   Reply With Quote
Old 09-27-2014, 02:16 PM   #17
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

If you pull the hose off, no fluid should come out.
You do know the screw for adjustment is inside the hose nipple.
Can you see the screw end when you look in there?
The pin goes in the end of the modulator when you install the modulator back in the tranny.
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 02:46 PM   #18
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

I do know how to adjust it, but it is in such a tight area that I have to remove it to adjust it. I can't even fit a small screw driver from an eye glass kit between the transfer, and modulator. I was not aware that the pin is small enough to fit in the modulator, as my knowledge of the transmission is limited. maybe the pin is missing, and that is why fluid is pissing out ? I changed it in my garage, and saw nothing come out, but it could have fallen on the support or something ? I have no way of looking in the hole where the modulator goes, so not sure how to prove whether the pin exist or not ?
carnut4real is offline   Reply With Quote
Old 09-27-2014, 03:21 PM   #19
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

The pin is about 1 inch long and looks like a small nail.
To see in a tight spot use a mirror and a flashlight. Shine the light in the mirror and angle the mirror where you want to see.
Maybe you didn't have the pin in there to start with. PO might have lost it.
No pin would cause your high shifting problem.
The pin slides right in the end of the modulator.
To make a tight fit 90 degree screwdriver I've used an allen wrench ground down on the end to fit in the hole.
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 03:28 PM   #20
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

Ok, I'll give it a try. I found a used pin on eBay, and it look like a small cam shaft. It's actually within driving distance of me, will the pin stick out or could it be flush with the hole it sits in, because when I put my finger in there I can feel something move, but it's flush ?
carnut4real is offline   Reply With Quote
Old 09-27-2014, 03:32 PM   #21
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

THe pin should fall out IIRC.
And It should stick out, not flush.
When you take it out, take a pic of it.
In fact, take a pic of the modulator before you pull it out.
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 04:14 PM   #22
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

ok, so I pulled the pin out with a pair of tweezers, and it looks like a cam shaft about 2.5" long. The last 1/8" appears to be spring loaded, so I'm not getting the modulator in all the way with the strap I made up. If this is causing the issue I am going to have to remove the broken bolt, so I can use the stock clamp ?
carnut4real is offline   Reply With Quote
Old 09-27-2014, 04:32 PM   #23
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

Is there a chance of a pic?
I don't recall a pin like that.
geezer#99 is online now   Reply With Quote
Old 09-27-2014, 04:50 PM   #24
carnut4real
Registered User
 
Join Date: Jul 2014
Location: Enfield NH
Posts: 31
Re: broken trans modulator bolt

http://i.ebayimg.com/00/s/MTE5NVgxNjAw/z/siwAAOSwPe1UFKFF/$_57.JPG
carnut4real is offline   Reply With Quote
Old 09-27-2014, 05:16 PM   #25
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,702
Re: broken trans modulator bolt

Linky no worky!!
geezer#99 is online now   Reply With Quote
Reply

Bookmarks


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 07:55 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com