Is anyone using the TA direct fit Viton seal (TA 1516) with success? My machinist recommended that I use a Cadillac seal (Mahle JV600). It's only $15 and he says he uses it all the time on Buick 455 without issue. I attempted to trim the seal per the Rear Main Seal Install sticky. I actually thought I did a pretty good job. I trimmed it to 0.008" above the parting line. I figured I'd split the difference between the recommended 0.005" to 0.010". It looked square, but when I installed it it wasn't even close. The two halves were barely touching and I clearly did not trim it squarely. So, now I'm wondering if I should continue going through seals until I get it right or go with the direct fit seal.
Good reading, including input from TA. https://www.v8buick.com/index.php?t...mend-the-bop-one-piece-rear-main-seal.383432/ Devon
Thanks for the feedback! After reading the referenced thread, I think I will try TA's no trim seal. I think the extra money spent will save me some time and frustration.
I've used the old TA/Ford seal and it last 13+ years. I recently weighed my options in a freshen-up and used the new TA Viton seal. Never mind the BOP seal or any seal that needs trimming. I think the Ford seal and the Caddy seal have been discontinued, or superseded back to a rope. Like I wrote in the linked thread, the TA seal is easy-peasy. For less than $50 more, why mess around? And good grief don't use any sealer in the grooves!!
Well, so much for no frustration! I test fitted the TA no trim seal and it bulged pretty badly. Since that capped off an otherwise frustrating day, I didn’t think to take a picture of it installed. I did however install one half some what flush with the parting line on the block to see how much it stuck up and I did the same thing with the other half of the seal in the cap. It extended a little bit above the block parting line, and a lot more in the cap. I flipped the two halves of the seal and the seal still stuck out quit a bit from the cap. (See pictures.) I double checked the groove in the cap and block to make sure there was no debris and they were clean. Any thoughts? Thanks, Jim
The T/A seal is trim to fit as the instructions say. It sticks up further than .020 more like .060. You need to measure how much it protrudes out with a dial caliper. And trim accordingly.
TA offers several seals. TA 1516 is a direct fit and TA 1516B is a trim fit. I bought the TA 1516 (direct fit). I assumed direct fit meant there was no trimming needed. Was that a bad assumption?
Are you still able to share an installed photo? The protrusion doesn't look too bad at first glance, obviously we're seeing it all on one side, but it's been a while since I've dealt with a rear seal. Devon
I’m building the engine at a friend’s house. I’ll try to get over there today or tomorrow, reinstall it, and take a few pictures.
As per the instructions for the 1516 direct fit seal states on line 4 that if the seal protrudes more than.040 seal must be trimmed both halfs.The attached pictures illustrate both the instructions and also how much the seal sticks out of a Buick cap three different blocks checked the exact same the amount the seal protrudes is..060. Also in my experience .040 still causes the seal to bulge at the parting line .015 to .020 seams to be the correct preload
I did see that, but since the instructions are used for six different seals and the 455 has a trim fit and direct fit, I assumed that part of the instructions applied to the trim fit seal. I'm going to test fit the seal again. I'm wondering if I had the seal shifted too far in the cap, so when I put the cap on the block, the seal bulged on one side and was barely touching on the other side. Once I saw the bulge on the one side I stopped seating the cap (although it was very close), so the seal in the block may not have shifted to the side that was not bulging to even out the preloud. I don't know ... just a thought. I give another try and see what happens.
I called TA and they confirmed that the TA 1516 (direct fit) seal does not require trimming. With that said, this whole conversation may be a moot point. Now I'm concerned that my engine is cracked even though I had it checked by an engine builder. That will be a topic for a soon to be new post. For the sake of obtaining some closure, and in hopes that I'm wrong about the crack, I'll share some pictures of the installed seal and the bulges.
Any thoughts on why the direct fit seal is not fitting correctly? I'm considering trying my luck again with trimming a Cadillac seal … if I get my cylinder wall issue straightened out.
How much material was removed during the line bore/hone? Are you sure you are pushing it all the way into the grooves?? I've never seen so many people have so many troubles with rear main seals, including some well-known Buick engine builders.. I'm not sure what is being done incorrectly. The old Caddy seal is likely made of nitrile rubber. Some would say TA's Viton seal that you have is better. Maybe call TA? My block in my convertible has been line honed once a long time ago, and the direct-fit TA Viton 1516 seal fit fine during a 13-year freshen-up last winter and is 100% leak free.
I purchased a couple of the 1516 seals installed them in three different blocks all three protruded out one side about .060 measured! which is way too much for a direct fit. That’s according to TAs own instructions clearly state that if the seal sticks up further than noted you must trim the seal as far as I am aware of there is no direct fit seal available. you may have a block that varies a few thousands no way it would change enough to create as much difference as I noted. You can clearly see in the picture I posted! And maybe installing one and not trimming it and it didn’t leak you got lucky however, I would not trust that much pre-load!It has to bulging at the parting line. do it right follow the instructions it’s not that big of a deal.
Tom, mine did not fit like that at all. Now I'm going to find a spare main cap or pull one off of a core and see how the spare seal I bought fits. I wonder if yours and Jim's are mis-bagged and are for the early AL blocks w/ the groove cut too deep. The old 1516 was the Ford 6-cyl seal (discontinued), which was a no-trim, direct fit (at least in my block anyway!). No doubt the instruction sheet and the catalogue can use a "tune-up".
Unfortunately, this is the second time I know of that the block has been align honed. The previous owner had it done once. I had it checked when the engine came apart and the engine builder said it didn't need to be align honed. Later, I took the block to another engine builder and I mentioned it didn't need an align hone, but for some reason he align honed it anyway. I'm not sure how much he took off. I double checked that nothing was in the grooves and the seal was fully seated, then I had a friend confirm that. Yeah, the instructions are use for multiple seals, so I figured the portion that discusses trimming did not apply to the 1516 seal. I did call TA and asked them and they stated that the direct fit seal does not require trimming. Obviously, I can't leave the seal the way it is. I either need to trim it or get a Cadillac seal and trim it. I spent the extra money on the direct fit seal so I didn't have to trim it. I may just return the TA seal and buy the Cadillac seal for a third of the price. That will give me three opportunities to get it right. I just checked my seal and it has a 1516 cast into it.
A line honing would not cause that much difference you’re talking a few thousands. You can’t go by just somebody telling you it does not require trimming put the damn seal in and measure it that will tell you. And if the seal is bulging at the parting line, then there’s a problem.
