12a oil pump chain
 

I'm sticking this '85 12a in a MGB and I had the pan off tonight to see how I can re design it so I could fit it behind the front cross member. I looked up and noticed the oil pump drive chain had more slop than I would have thought it would have.

So how much chain slop is too much? I have the pan off and am feeling it from the bottom. How tight are they when new?

Does a new one come with a master link and I could spin it around without taking the front cover off?

Push the center section between the top and bottom of the sprocket and pump. If you can push it more than 1/2 inch in from the original position, that is too much play.

And no, they do not come with a removeable link.

You can get the oil chain at www.rocauto.com for $15

can you get the oil pump off and the chain on from the bottom then or does the front cover have to come off?

The front cover must come off.

The E-shaft passes thru the chain, and thru the front cover. Also, the chain gear bolts onto the oil pump from the front, and you cannot get sufficient slack in the chain to remove it without first unbolting the chain gear.

To install the oil pump chain, you have to remove the front stack, which means removing the front cover. There's no workaround.

You guys make things harder than they need to be. I'm sure the oil pump chain is fine.

+ 1. :lol:

:dunno:

http://img.photobucket.com/albums/v2...tuff/chain.jpg

:icon_tup:

Thanks guys for the specs out of the book. I'll take another look at it and maybe I can convince myself it's good enough ;)

I guess I hoped that someone would post up that yes the OEM one is a crimped master and it all has to come apart but 54 links of #7 chain and a clip master works fine.

Better luck next time I guess.

I talked to the GF's father tonight and asked him to measure the slop in the chain.

He emailed back: 3/4" total slop back and forth. I thought that was bad news but It looks in the picture that you are supposed to measure it from a centered position (straight edge between the sprockets) and it pushed to one side.

So I guess that's ok since that would be 3/8 from centered?

Thoughts?

Oil pump chains practically never fail. How many posts for oil pump chains failing vs apex seals/clutches/trannies/you-name-it failing can you find on this forum? Search noob! Just kidding, but search to find your answer (yah noob! :) ).

Now that I'm working for transit I get to see the people that ride the short bus .... I'll say if I see ya
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I searched like crazy to try to find the spec on chain slop I found nothing so I posted.

Now you're posting that I should have ... searched for ?? ... I know chain issues are not a common problem that's why I had to post to find the spec.

Are you suggesting that because it's not a common problem I shouldn't measure it ?

I am a diesel equipment mechanic and for the last few years I've looked after the transit fleet here so I may not know a lot of spacific rotary info but I know that when you can almost cock a chain link back on it's self to skip a sprocket tooth it's worth finding out how to measure it.