5.3/TH350 starter issue
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5.3/TH350 starter issue I'm having trouble getting my starter to fit. I'm using the spacer and TCI flexplate. Ive got the spacer between the block and flexplate and the flexplate bolted to the converter. I've gone through some threads that suggest putting the spacer between the flexplate and converter but won't that leave a gap between the flexplate and converter? Maybe I'm overthinking it. The way it is now the gear housing for the starter hits the flexplate. I'm using a starter for an 05 5.3.
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From: Emory Texas currently
spacer is on wrong u need the spacer between the flexplate and torque converter if using the 5.3 flexplate my 6.0 is the opposite i just did it last night so its still fresh on my mind and my 5.3 i did a few weeks ago ive never had any issues with its lined up perfect every time as long as i had my spacer right
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From: Emory Texas currently
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Ok now I'm getting confused haha. With the flexplate bolted to the crank the starter lines up fine. But with the spacer in between the flexplate and converter there will be a huge gap. The reason I originally got the spacer was because there was a 3/8" gap between the converter and flexplate. Having the spacer/flexplate/converter combo fixed that. Maybe I'm going crazy but I'm thinking the starter is the issue.
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From: Longview, TX
Which TCI flexplate did you get?
I found this on another thread. Seemed to work out on the same set up with a TH400.
"TCI flexplate that should have the right pattern and came with the appropriate spacer to support the nose of the TH400 converter. It is TCI P/N 399754 and cost $225 through summitracing.com. It came with fasteners for attaching to the crank, but not for attaching to the converter. I used it for running the compression check and it engaged properly with the starter. I plan to mockup the stall converter on it next time the engine is on a hoist."
I found this on another thread. Seemed to work out on the same set up with a TH400.
"TCI flexplate that should have the right pattern and came with the appropriate spacer to support the nose of the TH400 converter. It is TCI P/N 399754 and cost $225 through summitracing.com. It came with fasteners for attaching to the crank, but not for attaching to the converter. I used it for running the compression check and it engaged properly with the starter. I plan to mockup the stall converter on it next time the engine is on a hoist."
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%5BURL=http://s222.photobucket.com/user/sharkbait_015/media/11EB51A9-A5DE-46DD-99CB-BDAE1CF48DE2.jpg.html%5D%5BIMG%5Dhttp://i222.photobucket.com/albums/dd143/sharkbait_015/11EB51A9-A5DE-46DD-99CB-BDAE1CF48DE2.jpg%5B/IMG%5D%5B/URL%5D
this was with the crank/flexplate no spacer combo. There is about a 3/8 gap between the converter and flexplate. The spacer between the flexplate and crank solved that. Just the starter issue.
I can't get any photos to load onto Photobucket right now for some reason but with the spacer between the flexplate and converter there would be a huge gap.
this was with the crank/flexplate no spacer combo. There is about a 3/8 gap between the converter and flexplate. The spacer between the flexplate and crank solved that. Just the starter issue.
I can't get any photos to load onto Photobucket right now for some reason but with the spacer between the flexplate and converter there would be a huge gap.
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BIG BRUTE - Starter to flexplate ring gear. help Ok now I'm getting confused haha. With the flexplate bolted to the crank the starter lines up fine. But with the spacer in between the flexplate and converter there will be a huge gap. The reason I originally got the spacer was because there was a 3/8" gap between the converter and flexplate. Having the spacer/flexplate/converter combo fixed that. Maybe I'm going crazy but I'm thinking the starter is the issue.
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From: Alaska
I’m a little confused by your post. What is a “short shaft” 5.3L? All LM7’s were truck and SUV engines with no real variations. Also, what year 4L60E are you running? If it’s a 99+ truck or suv unit, it should bolt up to an LM7 without any need for a spacer.
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Thanks for the reply - So from my research, most Gen III engines have a shorter crank shaft flange (off-set of about 4/10" closer to the block) where as 6.0L and 4.8L had a crank flang that extended 4/10" past other Vortec and other LS engines. I am totally baffled! My situation:
I have a 5.3 LM7 form a 2003 GMC Sierra (I originally had it mated to and advance adapters bell to a AX15 Manual transmission)
I now have a 2003 - 2006 (not sure exactly the year) 4l60e. (I have a separate computer from USShift to run it) I have to torque converter that came with it.
With the torque converter fully seated in the pump, there ends up being a a hug gap between the torque converter and the flexplate. (I have a dished flexplate). If I use the spacer between the flexplate and the crank, I have a perfect 1/8 inch - which is pretty much were I need to be) Problem is - The starter will now not reach the ring gear on the flexplate! frustrating.... (if I use a flat plaxplate with the spacer, it will be too large a gap.... If I don't use the spacer and I keep the dished flexplate, too large a gap.) Is there a different starter with a little longer gear/shaft I can get that will reach the extra 1/4 to engage the flexplate ring gear..). Hope this makes sense.... Thanks
I have a 5.3 LM7 form a 2003 GMC Sierra (I originally had it mated to and advance adapters bell to a AX15 Manual transmission)
I now have a 2003 - 2006 (not sure exactly the year) 4l60e. (I have a separate computer from USShift to run it) I have to torque converter that came with it.
With the torque converter fully seated in the pump, there ends up being a a hug gap between the torque converter and the flexplate. (I have a dished flexplate). If I use the spacer between the flexplate and the crank, I have a perfect 1/8 inch - which is pretty much were I need to be) Problem is - The starter will now not reach the ring gear on the flexplate! frustrating.... (if I use a flat plaxplate with the spacer, it will be too large a gap.... If I don't use the spacer and I keep the dished flexplate, too large a gap.) Is there a different starter with a little longer gear/shaft I can get that will reach the extra 1/4 to engage the flexplate ring gear..). Hope this makes sense.... Thanks
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From: Alaska
There is no extended starter for these engines. The only “odd crank” LS engines are the 99-00 6.0L with the iron heads - these had the long crankshaft, which stuck out an additional .400”. These used a flat flexplate.
The only reference of .400” shorter on LS engines, is when measuring crank protrusion from the bellhousing flange compared to an SBC crank. This is where the flexplate spacer comes in, when you are mating an LS engine to an SBC transmission and torque converter. Since you are using an LS 5.3L and LS specific transmission, you should not need the spacer as you are essentially using a factory combo.
Is the dished flexplate you have OEM, or aftermarket? Torque converter OEM as well? They should mate up with zero issues and no spacer.
The only reference of .400” shorter on LS engines, is when measuring crank protrusion from the bellhousing flange compared to an SBC crank. This is where the flexplate spacer comes in, when you are mating an LS engine to an SBC transmission and torque converter. Since you are using an LS 5.3L and LS specific transmission, you should not need the spacer as you are essentially using a factory combo.
Is the dished flexplate you have OEM, or aftermarket? Torque converter OEM as well? They should mate up with zero issues and no spacer.
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I’m with you 100%. This is why I am baffled. I though “plug and play” because this is the transmission that should fit perfectly. The torque convert is the one that came with the transmission. The flexplate is from NAPA and is for a 2003 GMC Sierra 1500 4x4 with 5.3 engine. It is dished (convex). It fits the convert and the crank flange like a glove. When spaced from the crank flang, to fit the torque converter, the ring gear on the flex-plate is to far from the starter gear, but perfectly spaced for the torque converter. Makes no sense - should there be spacers on torque converter to flexplate and maybe put the flexplate spacer on the front on the flax plate between the torque convert and fp?? Really makes no sense. And really frustrating. —— bottom line: 1. no spacer = way too much spacing between FP and torque converter. 2. Spacer between FP and crank = perfect spacing but starter won’t reach to engage... thanks again.
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From: Alaska
You really shouldn’t need anything spaced to make this work.
When you say there is too much room between the flexplate and the torque converter when everything is assembled as it should be normally, what exactly are you referencing? It is normal for the torque converter to slide out some to mate to the flexplate. When you slide the torque converter forward, does the snout seat against the crank flange at the same time that the bolt ears rest against the flexplate?
Edit: Can you also post a picture of the transmission, including the ID tag on top and the bellhousing? One possibility is you may have the wrong transmission or bellhousing.
When you say there is too much room between the flexplate and the torque converter when everything is assembled as it should be normally, what exactly are you referencing? It is normal for the torque converter to slide out some to mate to the flexplate. When you slide the torque converter forward, does the snout seat against the crank flange at the same time that the bolt ears rest against the flexplate?
Edit: Can you also post a picture of the transmission, including the ID tag on top and the bellhousing? One possibility is you may have the wrong transmission or bellhousing.
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With the spacer, there is 1/8 inch of space between the flexplate and the mount points of the torque converter. (Which is perfect)
Without the spacer, it is roughly an inch (give or take).
The torque converter pilot fits perfectly.
It is a 3KCD (2003 4l60e)
Without the spacer, it is roughly an inch (give or take).
The torque converter pilot fits perfectly.
It is a 3KCD (2003 4l60e)
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I am having same issue . The starter gear are not reaching the fly wheel all in after I replaced the engine and I used flex plate that I got from eBay. The 6.0 engine even though it is the same engine size I removed, this one has shaft protruding a-little more than the original engine. Please advise me how you solved this mystery.