8BA Crankshaft pulley problem

[tubman]

I got my 258 inch engine back from the machine shop. The machinist had done me the "favor" of installing a one-piece front seal, along with the requisite "Redi-Sleeve". I have never had a problem with properly installed rope seals leaking, so I have no experience with the one piece seals. I installed the new truck water pumps with no problem, but when I got around to installing the crankshaft pulley, it became obvious that it would have to be modified to fit. It looks like 1 1/4" has to be removed from the back of the pulley to make it fit. If I take that much off the pulley, I will lose most of the area in the bore that is sized to fit snugly on the crankshaft. The crank pulley I am using was represented to me when I purchased it as a '49 Mercury unit. When looking down the bore from this pulley (from back to front), there is 1 1/4 " of bore that fits the crank snugly; then there is a relieved area about 3/4" long. After that, there is another 3/4" bore that is sized to the crankshaft snout. If I shorten the pulley to fit, I will lose the 1 1/4" of support, leaving only 3/4" of support for the pulley. Is that enough? I will be going from 2" of support to less than an inch. Part of me says that should be enough, but another part of me is bothered by losing that much support area. Any suggestions will be welcomed.

Another problem is that the Mercury pulley is larger in diameter than the other 8BA crankshaft pulleys I have. Enough larger, in fact, that it will not clear the timing pointer installed in my aluminum timing cover. There seems to be enough room on the cover to drill another hole an re-locate the timing pointer. Is this the usual procedure to be used? Also, the pulley I have is for the wide belt, but it has two grooves, of which the inner one will line up with the water pumps if I trim it down as described. I am starting to wonder if the pulley I have is actually for a '49 Mercury; with the second groove, could it be from a large truck? I can make this all work, but I want to do this as easily and as correctly as I can.

Perhaps this would be the time to consider an aftermarket harmonic damper?

[flatheadmurre]

You need the later style pulley that had a separate spiral sleeve.
Cutting the pulley you have is a less good solution...they get wobbley and fail.
You could have installed a speedy sleeve on that pulley for the one piece sleeve.
And the timing covers usually have marks in the casting for 2 separate places of the needle depending on if it is wide or narrow belt pulleys.

[flatheadmurre]

Here are early and late truck wide belt pulleys and narrow car pulley.
Frontcovers truck and car style.

[Charlie ny]

The after mkt 'harmonic' pulleys I've crossed paths with have a common trait (in my
experience) ,the outer ring slips after a short time running. Hopefully this issue has
been addressed by the maker/s.
I gotta say if this was my build I'd take a deep breath yank it apart and toss the one piece seal and retro back to the rope and long pulley. This is only my opinion and I certainly respect any and all other opinions.
Charlie ny

[flatford8]

Originally Posted by flatheadmurre

Here are early and late truck wide belt pulleys and narrow car pulley.
Frontcovers truck and car style.

This is good info!!..... whats the difference in the covers?.... is it just the pointer location?.... Mark

[tubman]

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Charlie, I considered that, but was concerned about tearing apart a fresh "professional" build, and am especially concerned about what it will take to remove the "Speedy-Sleeve". It's still an option, however. That's why I'm on here looking for advice from the pros (you're one). Thanks for your input. I bought a one-piece seal from Speedway out of curiosity, and decided not to use it. The machinist says that this one is a new deal and is a lot better than the ones usually used. We'll see.

[tubman]

Originally Posted by flatford8

This is good info!!..... whats the difference in the covers?.... is it just the pointer location?.... Mark

Lots of differences; some aluminum, some cast iron, some with the provision for an extended shaft, some without, and the pointer thing. I 'm not fully knowledgeable about all of the combinations, just that you should check them for compatibility with your distributor (and now your crankshaft pulley).

[JSeery]

I would at least check with the builder about any warranty impact. I wouldn't want to mess with anything until the engine has been run to insure no major issues.

[flatheadmurre]

Late frontcovers come in 5 different styles atleast....
1. cast iron 8RT truck for widebelt and cast iron distributor
2. cast iron 8BA car for narrowbelt and cast iron distributor.
3. aluminum 8RT truck for widebelt and aluminum distributor.
4. aluminum 0BA car for narrowbelt and aluminum distributor.
Then there´s a version of aluminum frontcover that takes a cast iron distributor with no bottom support and additional reinforcement at the distributor mount...not sure if there was a car and a truck version of this to.....

[19Fordy]

Here is the pulley you need.
There is usually one on Ebay motors.
Not cheap.

[tubman]

"19Fourdy" - Thanks for the picture; I bought a narrow belt car pulley off eBay and I know what you mean about price. I bid on about a half dozen and lost, but finally got one at a price I thought was close to reasonable. I can only imagine what they want for one of these. Luckily "flatheadmurre" has an extra that he's bringing from Sweden when he comes to Minnesota next week for his annual parts hunt. I've sold a bunch of parts to guys there, so I guess it's time to reverse the favor.

Do you (or anyone) know what the pulley I have is from? I'll probably end up selling it and would like to be correct on the fitment. There is an "S" stamped on it, along with "8B" and a diamond with a couple of little letters inside it.

[19Fordy]

Sorry, I don't know what the pulley you have with the long "snout" fits.

[flatheadmurre]

It´s just the early style 8RT pulley that has the spiral integrated with the pulley.
Later ones are 2 piece with a separate "wearsleeve".
Both styles fit any 8BA/8RT/Merc with wide belt pumps.

[V8 Bob]

Testing. I am trying to post some pictures from my hard drive, since Photobucket now wants a fee, but they are too small. Thought I could delete the post but so far can't, so I'll finish the post and hope it helps.
The pictures show 4 types of front covers I have collected over the years. Covers A and B are alloy, while C and D are cast iron.
Cover A should only be used with the extended shaft alloy distributor, but has two pointer locations that allow use with the large sheet metal wide belt pulleys or the cast narrow belt pulleys.
Cover B also has two pointer locations but is designed for the cast iron distributor.
Covers C and D are cast iron with only one pointer location, and are also used with the cast iron distributor.
I don't think any one cover was intended for any one engine type, as all have been found on trucks, Fords and Mercs.

[rotorwrench]

The one with the built in spiral oil seal surface is the original issue of the part. Likely 1948 and early 49. The short one should work but the intent was for the pulley to seat against the sleeve to get the pulley secure and to align the belts properly. If the "speedy sleeve" is not large enough to clamp against, I would consider this a problem. Most speedy sleeves I've used in the past are very thin and can be removed by scoring the sleeve along it's length and then carefully getting under it with a chisel type tool to break it at the score line then peel it off. The ones made for the seal usually are sized to replace the separate spiral seal sleeve.

Personally, I don't do "favors" like this without the owner knowing what is going on. In this case, the favor is causing more work than you had originally planned to do. Not much of a favor in my book. These type seals work but if the old style ain't broke, don't try to fix it.

[tubman]

I was thinkin' truck, but the stamped "8B" makes me wonder.

[tubman]

Notice the word "favor" was in quotes on my original post. This sleeve seems to be at least 1/16" thick. Perhaps his improved one piece seal uses a sleeve analogous to those used on the later vehicles. If so, that would solve a lot of problems. These guys have access to parts us "normals" don't know about. I'll wait until I get the proper pulley and then make a final decision (which may involve tearing it down and using a rope seal).

Thanks for the help guys; this has been very enlightening.

[V8 Bob]

Sorry. Here are the pictues. This used to be so easy with Photobucket, now I have to learn another way. If you click on the pictures they should enlarge.

099.jpg

056.jpg

[Ol' Ron]

This is an excellent post, gives the phrase "plan Ahead" some real meaning. Building an engine is different than putting one together. In this case I just cut the pulley to fit, but sometimes that doesn't work, but I've had no trouble with that solution. However. I prefer to use the GM harmonic balancer, bored for a press fit to the crank then add or make a pulley. But planning this is the important part of building an engome.

[woodypecker]

I have a 51 or 52 8rt engine and the pulley from it has an S stamped in it but no 8ba outer diameter at pointer is 6 3/4 inch. It has a support length of two inches. One solution would be cut your pulley and have the guy that did you a favor make a bushing to slip inside your pulley and get the 2 inch support. the bushing needs a cut out section to fit over the key way. Good luck.