Packard Forum Index » V-8 (1955-56)

G'day Mates, has anyone had a problem with the NAPA RR158 distributor cap for a '56 Patrician. After getting my (Delco) distributor reworked recently I was going to fit a brand new cap that I had as a spare. When fitted while the distributor was still out of the car the rotor wouldn't complete a full rotation without solidly hitting a cap terminal. Checking inside the cap didn't show anything obvious that was out of whack so I have to assume that it's a manufacturing fault. I paid for two new caps as spares when I bought the car and one was, and still is, fitted to the car without any problems. I'm now wary of the NAPA product and am wondering if there is another brand in the US suitable for this car and readily available. I doubt I'll find anything over here unless another make/model car uses the same cap. Cheers, John

I'm now wary of the NAPA product and am wondering if there is another brand in the US suitable for this car and readily available

Yes, Standard Ignition's cap for a 55-56 Delco would be DR-427, assuming that part # is still current. I've had no problems with Echlin/NAPA parts but do happen to have a fairly new Standard cap on my Carib.

PS - many GM models used the same cap. I can generate a list for you if you wish.

Here are my thoughts. Maybe the end play of the distributor is causing the rotor to hit a cap contact because you tried fitting the new cap with it out of the engine. I would think that it would only be able to rotate about 45 degrees between contacts. Is it hitting all contacts or just one? Maybe the rotor and cap need to be from the same manufacturer. I would this this not likely, but it may be the case with your problem. Just some thoughts.

(o{I}o)

All GM 8 cylinder distributors of approx 53-56 used the same cap, so it shouldn't be too hard to source one. I am suprised you are having trouble with the RR158 as I have installed dozens with no problem. I'd check to be sure there is no flashing inside the rotor that might be holding it up a bit high. Also, on a V-8, pull down on the shaft as you turn it as they tend to have a lot of end play.

Hi JP, I experienced the exact same problem with a Standard Ignition cap for another make. I assume the terminal(s) are not correctly cast or positioned. It really seems as more of the replacement parts for our cars are outsourced to developing nations the quality gets worse and worse.

I had the same problem with my cap and rotor after ruling out the housing and shaft runout. Found the problem was the rotor itself the fit that goes over the shaft was oversize the rotor would rock on the shaft and hit the posts on the cap. After checking several old used rotors on the shaft found the NEW rotor hole was larger and allowed to much movement. Guess we all assume the new parts we purchase are of the same quality standards as the orignal name brand OEM parts. Looked on Ebay found a orignal Delco still sealed in paper and metal box.

Yes, there are many offshore rotors and caps which are sloppy-loose on the shaft or housing.
No, it is not always safe just to toss on a new cap/rotor and crank 'er up.
Maybe, since it is such a pain to pull the Packard V8 distributor, check carefully for correct feel. If the rotor wiggles or the cap slides around, there is the risk of contact and destruction.

jack vines

Yes, there are many offshore rotors and caps which are sloppy-loose on the shaft or housing.

That's for certain. I don't know the make or if it was missing the little clip inside the rotor (which some have) but a friend learned this the hard way with an IGT rotor; it was such a poor fit it slipped on the shaft and when the car started it blew the air cleaner to smithereens and did some minor sheet metal damage to the hood as well.

Just as good practice says we should always pay attention to the lubrication needs of distributors (which are generally neglected except for the oiler or grease cup), we should also always check for excess play in the shaft whenever the cap is off.

G'day Mates, sorry for the tardy response but apart from having a bit to do, it's the middle of winter over here and pretty cold in the shed. I don't know what I'm doing wrong but I actually prepared a response and went to upload a photo to it and the lot disappeared into the ether never to be seen again, so I'm trying again and holding my breath at the same time as I not the world's best typist and it takes awhile to write this stuff! This time I might actually submit the text and then edit and try to add the photo later.

OK, I dug out my spare distributor, which is a #1110865 and fitted with twin points (factory setup?) and, to my surprise, is also fitted with my other new spare NAPA #RR158 cap and NAPA #RR159 rotor button (as usual, the grey matter has failed me again). It seems I retained the original cap and rotor button for the replacement distributor in which I fitted the Pertronix kit (the theory being to carry a good distributor in the spares should the electronic one fail).

Anyway, I was able to compare both new NAPA caps, both on and off another distributor in good condition, and I can report they are different. One cap has brass terminals while the other has aluminium, and the inside terminal "tunnels" on the brass cap are wider. The cap that caused me to start this thread is the one with the aluminium terminals and it still has the same rotational problem on this distributor, leading me to the conclusion that the cap is the problem, more specifically probably a manufacturing fault, and unlikely to be the suggestions you all kindly offered.

I think this cap is headed for the bin and I will be looking to replace it, although as I now realise I still have a good spare the situation is not urgent. Owen, the GM caps you mentioned are likely to be my best bet over here so when you have the time, I would greatly appreciate a list of the relevant part numbers. Thanks in advance. Cheers, John

Sorry fellas, I've tried three times to upload this bxxxxy photo of the two caps but can't make it work. It's a JPEG of 1,222 KB's. I'll try a couple of more times.

Quote:John,

When doing lengthy posts, especially for a one finger typist like me, it's best to save it somewhere before you preview or post it. Reason being, I think, is that PackardInfo times out after a while, then when you try to post your post what it does is log you in again.

Regarding the pic size, that's probably the reason it's not uploading.

See you at Kangaroo Island.