Flex Plate Inspection Cover Help

[Richard J]

Hi all,

I’m looking for some help figuring out the correct inspection cover for my 69 RS/SS coupe that I am restoring. It’s a numbers matching 350 300hp with a turbo 350. I’ve had both the engine and tranny rebuilt and I’m now ready to put them back in the car. The car came without a starter but there was a 153-tooth flex plate and a plastic inspection cover found amongst the parts that came with the car. I’ve installed a nice rebuilt 8338 starter and a 168-tooth flex plate which I am being told was correct for that engine and trans. Now when I try to put the inspection cover that I have on the tranny it hits the bottom of the flex plate to the point it will grind a hole in it.

Wasn't the factory inspection plate metal and was there a unique one for the 168 tooth?
After searching the different parts outlets I’ve not had any luck finding a cover that would work so any input would be greatly appreciated.

[Petes L48]

I had a similar issue with a 67 L48 with a Powerglide.  Most of the parts sellers didn't even know there is a specific 168-tooth cover.  I finally found one at Summit of Jegs that would fit. The pan should be metal, not plastic.     

Looking at this further, I noted the 69 AIM only lists one inspection cover for the TH350 (UPC M38) so I'd assume they made one pan that would accommodate both the 153 and 168-tooth flexplate. By comparison, in the 67 AIM for M35, they list two part numbers for the pan, one for the L48 specifically.  So they probably would have done the same in 69, unless they made a "one-size fits all" cover.  That TH350 part number is 6261091.

The part number for the TH400 (UPC M40) pan is 3868810.  That one would definitely fit a 168-tooth, but I don't know if covers between a TH350 and TH400 are interchangeable.
 

 

[KevinW]

Is the th350 metal cover the same as this one? part number 15522128.  I'm just trying to figure out what I have.

[Richard J]

Kevin, your cover looks like the hole configuration as that on my TH350 from what I can see. My question is, is the bottom of the pan deeper on yours than the plastic one to allow for a 168 tooth flex plate. My plastic cover has a part number of 6261091 on the inside of it as Pete mentioned, but as I said earlier the 168 hits the bottom of it and won’t bolt up.
Would it be possible to PM me for some measurements?

[KevinW]

The pan is 7" deep at the center.  What is the plastic's measurement?

[Richard J]

Using your measuring method it looks like about 6 3/4 inches. I tried attaching a photo of my measurement of the plastic one but being new at this it wouldn't work. ( Most likely operator error) I also measured the starter opening and it is approx. 3" wide.

[KevinW]

Use the "preview" button, then the "attachments" selection appear below text box.  it opens additional buttons, then you can choose a local file to attach.

My starter hole is 2"wide by 3" deep, but there is plenty of metal to trim to dial in the starter hole.

The circumference of the flex plates is: 12.75" for 153 and 14" for 168.

So the radius for 153 is 6.375 and the 168 is 7".  This pretty much matches our measurements.  There is a little bit more room at the bottom of the cover due to the measuring tape tab not at bottom.  So I remeasured using a finer point and it is almost 7 3/8".  So it looks like the metal one is for the larger 168 tooth flexplate  

[KevinW]

PM sent BTW

[Richard J]

Kevin, yes I interested do you know what the cover came off of and what year?

[KevinW]

I can't find anything on the internet for that part number, but other covers with similar part numbers are 80s to early 90s.  I posted this cover a while ago asking for what it was an someone told me a TH350, but i cannot find that now

[big iron]

Richard,
 6261091 is the correct under pan  for 69 350 with 350 trans.
Bob

[Richard J]

Bob, thanks for your input. Then I guess that would mean I would have had a 153 tooth originally? If so then what starter would have been put on at the factory?

[KevinW]

Richard, the starter would probably a regular one, aluminum nose, bolts in-line, mostly 110831, but could be 1108420 (see this post  http://www.camaros.org/forum/index.php?topic=2779.0;all ).

Please let me know if you are planning to switch to the smaller flexplate, so I can stand down  

PS, I thought all the TH350's received the 153 flex plates too, but I do not have any 1st hand knowledge.  I do have the larger flywheel on my manual L48.

[big iron]

Richard,
Kevin W is correct, 1108361 1st design and 1108420 2nd design
Bob