2005-06 Jeep OPDA_CPS_Distributor Failure - Page 140

**lope** · 09-12-2011, 09:31 PM

Quote:

Originally Posted by Rubi4MyMrs

Lope, what does the pump end of your old distributor shaft look like? I think I remember seeing it but would take forever to find it.

Here's the comparison pic from the other thread I had. The one on the left is the old distributor. The shaft from the '05 unit has a more steeper wear pattern, wearing almost right on the edges, indicating to me that it must not be as snug a fit in the oil pump slot. By contrast, the old distributor shaft end's wear is very shallow, almost 1/3 across.

**flying_bosun** · 09-12-2011, 10:29 PM

Quote:

Originally Posted by lope

Here's the comparison pic from the other thread I had. The one on the left is the old distributor. The shaft from the '05 unit has a more steeper wear pattern, wearing almost right on the edges, indicating to me that it must not be as snug a fit in the oil pump slot. By contrast, the old distributor shaft end's wear is very shallow, almost 1/3 across.

Attachment 278268

Is the tab thicker? Is the thinner tab is changing the contact angle driving centripetally on the shaft's center and warping the shaft? It's not that simple, is it?!

I just looked at both my original with 60K and the second with 2K; the heavy wear on the upper bushing is approximately 180 degrees from the most heavily worn tab. Can anyone look at theirs or measure an '04?

(Edit: Are the shafts from the different versions the same OD?)

Heath · 09-12-2011, 11:07 PM

Quote:

Originally Posted by flying_bosun

Ia the tab thicker?. Is the thinner tab is changing the contact angle driving centripetally on the shaft's center and warping the shaft? It's not that simple, is it?!

I just looked at both my original with 60K and the second with 2K; the heavy wear on the upper bushing is approximately 180 degrees from the most heavily worn tab. Can anyone look at theirs or measure an '04?

(Edit: Are the shafts from the different versions the same OD?)

Anything is possible.

I've wondered how straight the late model cam bore and distributor bores are in the casting/machining of the block.

stock'89YJ · 09-13-2011, 11:54 AM

Thanks all for the help. Pulled the old OPDA and it looks completely worn. Jeep has 155000 km on it. No problems pitting the new one in, I will start it later on today. Don't anticipate any problems. Engine and OPDA are both TDC. I will try to post pics later as well.
Ps. The cam shaft gear looks pretty bad. Looks like I will need a rebuild soon.

**flying_bosun** · 09-13-2011, 02:11 PM

Quote:

Originally Posted by flying_bosun

Is the tab thicker? Is the thinner tab is changing the contact angle driving centripetally on the shaft's center and warping the shaft? It's not that simple, is it?!

I just looked at both my original with 60K and the second with 2K; the heavy wear on the upper bushing is approximately 180 degrees from the most heavily worn tab. Can anyone look at theirs or measure an '04?

(Edit: Are the shafts from the different versions the same OD?)

Dead end, I'm afraid. Just got the '04 distributor tab measurement from another member and it's narrower by .001".

Why the difference in the contact patch between the two versions?! They use the same oil pump according to what I've found.

**undercoverfab** · 09-13-2011, 02:39 PM

Quote:

Originally Posted by flying_bosun

Dead end, I'm afraid. Just got the '04 distributor tab measurement from another member and it's narrower by .001".

Why the difference in the contact patch between the two versions?! They use the same oil pump according to what I've found.

Could be a difference in the hardness of the shaft...

**Rubi4MyMrs** · 09-13-2011, 05:16 PM

Quote:

Originally Posted by undercoverfab

Could be a difference in the hardness of the shaft...

That is my opinion based only on what is happening to these shafts & also based on the experience I had installing my Crown gear as referenced earlier. I think tkki might have some input on this. I know he had one hardened & it did not show an improvement but I don't know how hard it started out or how hard he got it to.

**tkki1230** · 09-13-2011, 05:56 PM

Quote:

Originally Posted by Rubi4MyMrs

That is my opinion based only on what is happening to these shafts & also based on the experience I had installing my Crown gear as referenced earlier. I think tkki might have some input on this. I know he had one hardened & it did not show an improvement but I don't know how hard it started out or how hard he got it to.

The hardening that I did was only a surface kind of thing. The nitriding treatment only penetrated in a thousandth or so.

LJameson · 09-14-2011, 02:49 PM

A bit off topic but interesting...

2000-2008 Ford Vulcan 3.0 engines have the exact same problem with their OPDA. It dries up, starts to seize and doesn't let the engine rev above 3000. I'll take a closer look next time I replace one, but I'm positive that it had a decal on it from the same parts supplier. I haven't taken one apart, but I wouldn't be surprised if it had the same crappy design. At least Chrysler only used it for 2 years, ford kept using it for 8 years.

rwh63 · 09-14-2011, 07:46 PM

do we have a head count from this thread on how many here have experienced this problem? this thread is quite long, but i'm not sure how many individuals have had an actual problem.

**Jeffro06** · 09-14-2011, 08:03 PM

Quote:

Originally Posted by rwh63

do we have a head count from this thread on how many here have experienced this problem? this thread is quite long, but i'm not sure how many individuals have had an actual problem.

Let's find out.... http://www.jeepforum.com/forum/f9/po...es-no-1265072/