Should the Torque converter be moved up during install?

Myasylum

Well-Known Member
Local time
4:31 PM
Joined
May 10, 2020
Messages
235
Reaction score
47
Location
53024
Hi, I have everything in place for my rebuilt transmission. But the flex plate is about 1/2" away from the torque converter.
The torque converter is all the way back in the transmission. Can it be pulled up 1/2"?

Thanks@

20220922_205236.jpg
 

Myasylum

Well-Known Member
Local time
4:31 PM
Joined
May 10, 2020
Messages
235
Reaction score
47
Location
53024
Is that a yes, it's OK to move up a half inch?

20220922_210701.jpg
 

Dave6T4

Well-Known Member
Local time
5:31 PM
Joined
Dec 31, 2020
Messages
2,888
Reaction score
5,115
Location
Ontario, Canada
Yes, that is the way it should be. Torque converter should not be bottomed out on pump drive lugs.
 

zyzzyx

FBBO Gold Member
FBBO Gold Member
Local time
4:31 PM
Joined
Aug 5, 2011
Messages
3,029
Reaction score
3,925
Location
Lisle, Illinois
The convertor should be 1/8" to 3/16" away from the flex plate when pushed forward. If the gap
is more than that, you should shim it with hardened washers. Unfortunately, you may need longer
bolts. 1/2" is more than twice the gap that it should be. There are numerous videos on YouTube
on this subject. Yes, not enough gap would be binding on the pump impeller.
 

Myasylum

Well-Known Member
Local time
4:31 PM
Joined
May 10, 2020
Messages
235
Reaction score
47
Location
53024
See that is what I was reading too but that was for a Chevy, I thought I'd ask on this forum since it's a Mopar forum, and it may be different. Everyone else here just says bolt it up.

Then people wonder why I ask. Misinformation everywhere.

However if others have bolted this up with a 1/2" gap and it worked for them, maybe there is nothing to worry about...
 
Last edited:

Fran Blacker

FBBO Gold Member
FBBO Gold Member
Local time
5:31 PM
Joined
Sep 23, 2016
Messages
12,629
Reaction score
12,630
Location
Connecticut
I'd add a Hardened washer or two. Would not what the pump just caught or to deep. MO.
 

mopar 3 B

Well-Known Member
Local time
4:31 PM
Joined
Aug 25, 2014
Messages
11,352
Reaction score
8,530
Location
Kingsville, MO
I have never pulled one apart in over 40 years that the factory felt washers were required and there is no mention of it in the FSM. So do what you want if you think it will do any good.
 

R413

Well-Known Member
Local time
2:31 PM
Joined
Feb 4, 2019
Messages
3,322
Reaction score
6,591
Location
NW USA
The hub of the converter needs to pilot into the back of the crankshaft. So this adding a washer idea is not a good one.
 

zyzzyx

FBBO Gold Member
FBBO Gold Member
Local time
4:31 PM
Joined
Aug 5, 2011
Messages
3,029
Reaction score
3,925
Location
Lisle, Illinois
The three things that engage the torque convertor are the input spline which rotates, the Stator support
that keeps a part inside the convertor stationary, (hence the name Stator) and the two front pump lugs
that pump oil through the trans. The two splines are fine just about with any gap, but the pump gear
is about 3/4" thick and needs to be driven with as much of the two cutouts in the nose of the convertor
without pushing it up against anything causing wear, chips, shavings, etc. It needs to operate in a "Free"
state so the gap is just a close figure. I had a friend with a Buick GS and while no gap didn't hurt his trans,
it kept pushing on his crank and ate through the thrust bearing and into the block! What a Hot Mess! Maybe
his convertor ballooned too adding to the failure. As far as the convertor piloting into the crankshaft, the
pilot on the convertor slides into the crank about an inch and a quarter, so shimming it 3/8" won't bother it.
 

mopar 3 B

Well-Known Member
Local time
4:31 PM
Joined
Aug 25, 2014
Messages
11,352
Reaction score
8,530
Location
Kingsville, MO
The three things that engage the torque convertor are the input spline which rotates, the Stator support
that keeps a part inside the convertor stationary, (hence the name Stator) and the two front pump lugs
that pump oil through the trans. The two splines are fine just about with any gap, but the pump gear
is about 3/4" thick and needs to be driven with as much of the two cutouts in the nose of the convertor
without pushing it up against anything causing wear, chips, shavings, etc. It needs to operate in a "Free"
state so the gap is just a close figure. I had a friend with a Buick GS and while no gap didn't hurt his trans,
it kept pushing on his crank and ate through the thrust bearing and into the block! What a Hot Mess! Maybe
his convertor ballooned too adding to the failure.
Why are we bring up GM crap issues on a MOPAR form. WP resolved those issues years ago when he started up Chrysler.
 

zyzzyx

FBBO Gold Member
FBBO Gold Member
Local time
4:31 PM
Joined
Aug 5, 2011
Messages
3,029
Reaction score
3,925
Location
Lisle, Illinois
Because the GM trans front pump is very similar to the 727. GOT IT?
 

Dave6T4

Well-Known Member
Local time
5:31 PM
Joined
Dec 31, 2020
Messages
2,888
Reaction score
5,115
Location
Ontario, Canada
In 40 years of working with 727's, I have NEVER seen washers or shims at torque converter mounts. The distance from the engine to the transmission mount face (rear of engine block) to converter mounting surface on the drive plate is a defined distance. The distance from the front of the transmission to the oil pump mounting surface is also a defined distance. These measurements are constant and do not change from engine to engine or transmission to transmission. The pump drive slots on the converter neck are way deeper than the oil pump drive lugs are thick. As long as you felt 3 definite engagements when you put the torque converter on, you are good to go. Nothing wrong with having to move converter ahead 1/2" to bolt to drive plate. It is when you have no clearance here when you have to worry. That means the oil pump drive has not engaged.
 

toolmanmike

Henchman #2
Staff member
FBBO Gold Member
Local time
4:31 PM
Joined
Aug 11, 2010
Messages
8,688
Reaction score
15,017
Location
Iowa
In 40 years of working with 727's, I have NEVER seen washers or shims at torque converter mounts. The distance from the engine to the transmission mount face (rear of engine block) to converter mounting surface on the drive plate is a defined distance. The distance from the front of the transmission to the oil pump mounting surface is also a defined distance. These measurements are constant and do not change from engine to engine or transmission to transmission. The pump drive slots on the converter neck are way deeper than the oil pump drive lugs are thick. As long as you felt 3 definite engagements when you put the torque converter on, you are good to go. Nothing wrong with having to move converter ahead 1/2" to bolt to drive plate. It is when you have no clearance here when you have to worry. That means the oil pump drive has not engaged.

you're right you know..jpg
 

Top