blazin_blazer
1/2 ton status
that means .....uhh, that means, uh,...your halucinating...b/c its not possible
iirc 1 piece is on 3'' circle and 2 piece is, on i believe 3.25'' circle
CK5
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1pc or 2 pc rear main seal?
- Thread starter Artemis Entreri
- Start date
that means .....uhh, that means, uh,...your halucinating...b/c its not possible
iirc 1 piece is on 3'' circle and 2 piece is, on i believe 3.25'' circle
chevyuser74
1/2 ton status
my engine in 74 has a 2 pc rear seal, i know this cus i had to replace it, the flexplate bolted to it is from an 87, i know this because i bought it when i swapped in the 700r4, so is my engine a freak of nature?
Randy92782
1 ton status
So yours would work seeing as how the 2 pc is bigger. Was there a gap anywhere??
chevyuser74
1/2 ton status
no i dont think so i could take a picture of it, the engine is back out of my truck cus i wanted to rebuild it for some more power
Sorry but a flexplate for a 1 piece rear seal ABSOLUTELY POSITIVELY WILL NOT bolt up to a 2 piece rear seal engine. The 2 piece rear seal engines have a 3.58" bolt circle for the flexplate and the 1 piece has a 3" bolt circle for the flexplate.
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chevyuser74
1/2 ton status
is it possible i have a 1 peice crank in my engine?
You cannot install a 1 piece seal crank into a 2 piece seal block but it is possible to do the opposite with the use of a special adapter.
chevyuser74
1/2 ton status
well i have a pioneer fra159 flexplate bolted to the back of my 2pc seal block i can take a pic if u like.
Sure, take a pic but also a pic of the back of the crank. The flexplate would have a balance plate welded to it if it was from a 1 piece rear engine as ALL SBC engines built 1986 and later are externally balanced on the rear.
The Pioneer FRA159 is for a 1 piece rear seal engine so if it is bolted to your crank then your engine is 1986 or newer.
The Pioneer FRA159 is for a 1 piece rear seal engine so if it is bolted to your crank then your engine is 1986 or newer.
chevyuser74
1/2 ton status
i guess i would learn that my block is probably newer then but why the 2 peice seal then?
chevyuser74
1/2 ton status
im not trying to be difficult or a smart ass or anything im just curious/confused more or less.
You need to take pics of the back of the crank. It is impossible to have a 2 piece seal crank with a 1 piece seal flexplate.
So where is the pic of this flexplate you have? Are you positive on that Pioneer part number?
chevyuser74
1/2 ton status
my engine is at work so i cant get pics till tomorrow, but yea im sure on the part number, the receipt is probably in my files somewhere. i bought it probably 2 years ago but i remember it distinctively cus my cost at carquest was 20 dollars more with my discount, than autozone sold the same part/brand for to everyone.
Take pics tomorrow of BOTH sides of the flexplate and also the back of the crank and post them here.
Slapperbar
Retired Navy NDT Examiner
Subscribed out of curiosity.
Are you sure you understand what makes it a 2 piece seal? Did you replace the seal from under the engine and install one half at a time? Or install the new seal on the back of the block with the tranny removed?
chevyuser74
1/2 ton status
dropped the pan took the cap off put in the 2 peice seal, i took pictures but left my camera at work
dropped the pan took the cap off put in the 2 peice seal, i took pictures but left my camera at work
Come on, don't leave us all hanging now.
Did you take pics of BOTH sides of the flexplate and also the back of the crank? Also, how about taking another pic of the flexplate with a tape measure across two of the mounting holes opposite of each other (180* apart), this will show us the bolt circle (either 3" or 3.58").
chevyuser74
1/2 ton status
i cant take pictures of both sides of the flexplate with it off cus i really dont feel like messing with it cus the engine stand makes it less easy to take off but i took pics all the way around and one with a tape measure to show the bolt pattern, also the pics obviously show no aluminum bracket to hold the 1 piece seal the bolt pattern is approximatly 3.5 inches i took a bunch of pics from a different angles
Ok, if your engine has a 2 piece rear seal and a 3.58" bolt circle flexplate that would be correct. The 3.58" bolt circle is for a 2 piece seal engine not a 1 piece seal engine so the FRA159 flexplate number you gave is the wrong number and would never bolt up as that flexplate has a 3" bolt circle.
