Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Random bolt size question...

Thread Tools
 
Search this Thread
 
Old 03-26-2019, 11:49 PM
  #1  
Member

Thread Starter
 
micktroup's Avatar
 
Join Date: May 2005
Location: California
Posts: 238
Likes: 0
Received 1 Like on 1 Post
Car: 1991 Z28 Camaro
Engine: 5.7L V8
Transmission: auto
Random bolt size question...

I have two missing bolts I need to replace: 1) the bolt that holds the fuel line bracket to the front of the driver's side head on my 5.7L TPI is missing. 2) One of the bolts that retains the throttle position sensor has sheared off flush with the throttle body(previous owner, not me!).

Anyone know what size bolts they are and where to get them?
Old 03-27-2019, 01:55 PM
  #2  
Senior Member
 
427seven's Avatar
 
Join Date: Jan 2019
Posts: 571
Received 482 Likes on 233 Posts
Car: 1989 Firebird GTA
Engine: Motown Aluminum 427
Transmission: TH400/GVO
Axle/Gears: Dana 44 IRS 3.75:1
Re: Random bolt size question...

Any chance you could take a pic of the bolt sites on the engine and post....?
Old 03-27-2019, 02:29 PM
  #3  
Supreme Member
iTrader: (1)
 
GeneralDisorder's Avatar
 
Join Date: Mar 2017
Location: Portland, OR
Posts: 4,255
Received 422 Likes on 323 Posts
Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Random bolt size question...

For the throttle body - pull the other one and measure it. Calipers and a thread gauge.

For the other - find something that threads in an measure that. It's likely SAE If it's going into the head. So probably 5/16 or 3/8. Likely a coarse thread. So either 5/16 x 18 or 3/8 x 16.... would be my wild a$$ guess.

GD
Old 03-27-2019, 02:35 PM
  #4  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,408
Received 649 Likes on 573 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Random bolt size question...

For the tps it’s a odd metric size 4.5mm iirc. You can ask in the wanted classifieds section. Or retread to a fine thread machine screw.
i think it’s 11/64
Old 03-27-2019, 08:14 PM
  #5  
Supreme Member

iTrader: (58)
 
Drew's Avatar
 
Join Date: Jul 1999
Location: Salina, KS
Posts: 20,309
Received 1,052 Likes on 748 Posts
Re: Random bolt size question...

Get the TPS screw from the junkyard. Look for any same generation GM, TBI, TPI, EFI V6, etc should all be about the same. Worst case, drill and tap the next size larger for a standard machine screw.

The fuel line clamp bolts to the exhaust manifold stud until 88, when it started bolting to the serpentine bracket. m8x1.25x16 is the serpentine bracket bolt.
Old 04-07-2019, 08:37 PM
  #6  
Member

iTrader: (1)
 
gta90's Avatar
 
Join Date: May 2008
Location: Southwest
Posts: 119
Received 0 Likes on 0 Posts
Car: 1990 GTA (T-Top)
Engine: 305 TPI (LB9) / 115k miles
Transmission: 4L60 (MD8 non-E)
Axle/Gears: 2.73 (GU2) 28 spline POSI (G80)
Re: Random bolt size question...

Bolts are cheap. Go to your local hardware store and pick up a couple bucks worth. Ace, True Value, etc. They sell grade 8's too. Dont waste your time and money at the dealership or junkyard.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Roc THIS
NW Indiana and South Chicago Suburb
10
08-03-2010 07:09 PM
1LEZ
Engine/Drivetrain/Suspension Parts for Sale
1
11-11-2009 10:38 AM
Tater13150
Tech / General Engine
1
12-30-2002 11:11 AM



Quick Reply: Random bolt size question...



All times are GMT -5. The time now is 09:44 PM.