How to change your OPDA

Also, once you get the OPDA out, shine a flashlight down the rabbit hole and look T the camshaft gear. If your OPDA gear is jacked up, there is a chance your camshaft gear is as well. Unfortunately, the only way to fix this involves a new camshaft.
 
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I just received these from the guy I trans swapped with. Figured they're worth the share so people know what to look at in cheap replacement - this has a 2014 manufacturing date printed on whatever brand it is. His PO swapped it.

You can test for this without even pulling the OPDA by removing the plastic cover and pulling up on the plate. If it moves more than maybe 1/16" you know it's worth pulling to check.

It appears this is a dorman OPDA. One of the stickers: 689-201

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I just received these from the guy I trans swapped with. Figured they're worth the share so people know what to look at in cheap replacement - this has a 2014 manufacturing date printed on whatever brand it is. His PO swapped it.

You can test for this without even pulling the OPDA by removing the plastic cover and pulling up on the plate. If it moves more than maybe 1/16" you know it's worth pulling to check.

It appears this is a dorman OPDA. One of the stickers: 689-201

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For those that may not have the same spatial assessment skills as others, the amount of wear that the drive gear caused on the bottom of the housing is just slightly less than what it would take to disengage the lower end from the oil pump. Had it kept going much more, he likely would have smoked the engine due to lack of oil pressure.
 
Yikes! Anybody else seen this happen on their dorman OPDA? Wonder how many people have preventatively replaced a Mopar OPDA with one of these only to jump from the frying pan into the fire?
 
I'd be worried about what's in all the bearings and such, but this is what came out from the oil pan. I don't think that housing is magnetic either, so no way to catch the nuggets aside from a few early oil changes and a prayer.

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I'd be worried about what's in all the bearings and such, but this is what came out from the oil pan. I don't think that housing is magnetic either, so no way to catch the nuggets aside from a few early oil changes and a prayer.

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For those that may not have the same spatial assessment skills as others, the amount of wear that the drive gear caused on the bottom of the housing is just slightly less than what it would take to disengage the lower end from the oil pump. Had it kept going much more, he likely would have smoked the engine due to lack of oil pressure.
What we are seeing here is a either the reluctor wheel assembly has worn into the top OPDA housing where it sets against the top bushing or the reluctor wheel has slipped on the shaft. Thus allowing to much gap at the bottom of the OPDA housing thrust bearing and the gear, the thrust bearing then dislodged and got chewed up.

Since the lower bushing of the OPDA is flush with the bottom of the housing the gear was then riding against the bushing once the thrust bearing was gone. There was no danger of losing oil pressure.

The real issue is what caused the OPDA shaft to drop down causing the failure. Could you show us pictures of the bottom of the reluctor wheel?

Thanks
 
What we are seeing here is a either the reluctor wheel assembly has worn into the top OPDA housing where it sets against the top bushing or the reluctor wheel has slipped on the shaft. Thus allowing to much gap at the bottom of the OPDA housing thrust bearing and the gear, the thrust bearing then dislodged and got chewed up.

Since the lower bushing of the OPDA is flush with the bottom of the housing the gear was then riding against the bushing once the thrust bearing was gone. There was no danger of losing oil pressure.

The real issue is what caused the OPDA shaft to drop down causing the failure. Could you show us pictures of the bottom of the reluctor wheel?

Thanks

Not quite, the arrow points to where the OPDA sits on the engine block. This was pushed up and chewed through the metal past the thrush washer, which means the flat end of the OPDA was within a very small threshold before dislodging and losing oil pressure.

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From what I can see in your pictures the gap between the gear and housing is way greater than the amount wore off the bottom of the housing and missing thrust washer, see images. Maybe 1/16 " of the gap is from the thrust washer and wear which is not enough to account for the gap we are seeing. The gear is a pined to the shaft so that is not where the gap is coming from. So only thing left is that something in the head/top of the OPDA is either worn or has come loose.

Could you post a couple of pictures of the inside of the OPDA?

Thanks.



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Does anyone know if the oil pump can be turned manually from the OPDA shaft opening? After replacing my camshaft I’m trying to get the new OPDA to align correctly.
 
Don't have any flat head versions of those around. I only have access to the flat head V8's.

Well , I hoped you might have had a hurricane or super hurricane lying around in Jeep world.
Hey, Merry Christmas to you and your wife!