Connecting rod shims
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
-
Topic author - Posts: 67
- Joined: Fri Jan 17, 2020 6:51 pm
- First Name: Carson
- Last Name: Combs
- * REQUIRED* Type and Year of Model Ts owned: 1924 touring, 1923 roadster pickup project
- Location: Las Vegas, Nevada
- Board Member Since: 2020
Connecting rod shims
So, I lost the brass shims for one of my connecting rods while taking apart my motor several months ago. I ordered a set of new ones, but they are way too thick and the clearance is much more than it should be. The plastigauge was hardly phased after I tightened down my cap when I was checking it. I also tried putting the cap on with no shim to see if it would be within spec. It didn't look good either.
Here's a picture after I put the cap on with no shims The shims that were in my motor (and still are on the rest of the rods) are clearly much thinner than the repros I bought from langs. The repro ones are .003
Is there a way I could file the shims down to fit, or another way I could fix this? Thanks in advance
Here's a picture after I put the cap on with no shims The shims that were in my motor (and still are on the rest of the rods) are clearly much thinner than the repros I bought from langs. The repro ones are .003
Is there a way I could file the shims down to fit, or another way I could fix this? Thanks in advance
-
- Posts: 7391
- Joined: Sun Feb 14, 2021 10:08 pm
- First Name: Pat
- Last Name: McNallen
- * REQUIRED* Type and Year of Model Ts owned: 1926-7 roadster
- Location: Graham, Texas
- Board Member Since: 2021
Re: Connecting rod shims
Some shims are "peelable", that is, they are made of several very thin shims glued together. You can carefully peel off layers to get the correct fit. You have to be careful not to bend the shims. They need to stay flat.
I don't think you could get good results trying to file or sand down a shim.
I don't think you could get good results trying to file or sand down a shim.
-
- Posts: 4634
- Joined: Tue Jan 08, 2019 1:39 pm
- First Name: Norman
- Last Name: Kling
- Location: Alpine California
Re: Connecting rod shims
I agree with Pat. Also I like to keep the old shims from my engines when I work on them. Usually if you have done a number of engines several times, you will acquire a collection of shims in various thicknesses so you can stack them to give the correct fit.
Norm
Norm
-
- Posts: 5171
- Joined: Sun Jan 06, 2019 12:18 pm
- First Name: Steve
- Last Name: Tomaso
- * REQUIRED* Type and Year of Model Ts owned: 1914 Touring, 1919 Centerdoor, 1924 TT C-Cab Express, 1925 Racer
- Location: Longbranch, WA
- Board Member Since: 2001
Re: Connecting rod shims
Carson - do you always use the metric system of measurement ? You are attempting to get the clearance between .001 - .0015 thousands. I have an envelope of used shims from other engines - be glad to send you an assortment in an envelope !
-
- Posts: 1241
- Joined: Mon Jan 07, 2019 8:01 am
- First Name: Mark
- Last Name: Nunn
- * REQUIRED* Type and Year of Model Ts owned: 1926 Runabout
- Location: Bennington, NE
- Board Member Since: 2017
Re: Connecting rod shims
Heat the shim stack with a lighter. The layers will separate for easy removal. It is not a solid piece.
-
- Posts: 4725
- Joined: Fri Feb 12, 2021 12:24 pm
- First Name: john
- Last Name: karvaly
- * REQUIRED* Type and Year of Model Ts owned: 14/15 wide track roadster. 23 touring, 27 roadster pickup, 20ish rajo touring
- Location: orange, ca
- Board Member Since: 2020
Re: Connecting rod shims
Turn the paper sleeve over for English readings.
-
- Posts: 3699
- Joined: Tue Jan 08, 2019 10:43 am
- First Name: Larry
- Last Name: Smith
- * REQUIRED* Type and Year of Model Ts owned: 13 Touring, 13 Roadster, 17 Coupelet, 25 Roadster P/U
- Location: Lomita, California
- MTFCA Life Member: YES
Re: Connecting rod shims
I've been making my own shims for years, because what's available doesn't do the job. The .003" shims are fine, but I've had to make .002" and .001" shims to get the job done. I've also had to do the same thing for the mains.
-
Topic author - Posts: 67
- Joined: Fri Jan 17, 2020 6:51 pm
- First Name: Carson
- Last Name: Combs
- * REQUIRED* Type and Year of Model Ts owned: 1924 touring, 1923 roadster pickup project
- Location: Las Vegas, Nevada
- Board Member Since: 2020
Re: Connecting rod shims
Thank you guys. I decided I'd try to find something that would work to make my own shim before I get some used ones.
I figured out this aluminum can that held my soda was almost the perfect thickness when I doubled the thickness, so I cut a model of a shim. Do you guys think this will work? Or should the shim be made of brass?
I figured out this aluminum can that held my soda was almost the perfect thickness when I doubled the thickness, so I cut a model of a shim. Do you guys think this will work? Or should the shim be made of brass?
-
- Posts: 86
- Joined: Sun May 16, 2021 3:05 pm
- First Name: Cap
- Last Name: Weir
- * REQUIRED* Type and Year of Model Ts owned: 24 & 25 C Cab
- Location: Atascadero,Ca
Re: Connecting rod shims
Aluminum is fine..
Soda Can... Beer Can.. Aluminum Foil.. Used all of them..
Cap
Soda Can... Beer Can.. Aluminum Foil.. Used all of them..
Cap
-
- Posts: 1906
- Joined: Tue Jan 08, 2019 12:22 am
- First Name: craig
- Last Name: leach
- * REQUIRED* Type and Year of Model Ts owned: 1919 Firetruck/1922 Speedster
- Location: Laveen Az
Re: Connecting rod shims
I found news paper in one once? I don't recomend it but it worked.
Craig.
Craig.
-
- Posts: 1241
- Joined: Mon Jan 07, 2019 8:01 am
- First Name: Mark
- Last Name: Nunn
- * REQUIRED* Type and Year of Model Ts owned: 1926 Runabout
- Location: Bennington, NE
- Board Member Since: 2017
Re: Connecting rod shims
It must have been "hard news", not that fluff on the back pagesCraig Leach wrote: ↑Tue Aug 08, 2023 10:58 amI found news paper in one once? I don't recomend it but it worked.
Craig.

-
- Posts: 1447
- Joined: Mon Jan 07, 2019 2:42 pm
- First Name: Frank
- Last Name: van Ekeren
- * REQUIRED* Type and Year of Model Ts owned: 1916 touring, 1916 pick-up, 1924 coupe, 1926 touring, 1927 touring
- Location: Rosedale Vic Australia
Re: Connecting rod shims
T Fords never left the factory with metal shims in the rods, parts supplied rods had a paper shim called a broaching shim and was .003" thick that could be removed, then the filing of the cap was the way for adjustment.
-
- Posts: 3699
- Joined: Tue Jan 08, 2019 10:43 am
- First Name: Larry
- Last Name: Smith
- * REQUIRED* Type and Year of Model Ts owned: 13 Touring, 13 Roadster, 17 Coupelet, 25 Roadster P/U
- Location: Lomita, California
- MTFCA Life Member: YES
Re: Connecting rod shims
I just checked McMaster Carr. They have what you need in steel or brass. .001"-.003".