TR - Removing wires from distributor cap

i had mine cleaned just recently, best to clean them but sorry i dont know how. ...dont ask me why, what, but they are different and not interchangeable...and of course you need to purchase these from MM with ferrari. Replaced mine in 2005 because they were 19 yrs old and original, and my bill shows 800.50 CDN for the left one and 899.99CDN for the right one back in 2005...im assuming they are kissing almost $1,000 by now.

 

I removed both sets of wires and caps from my ex-TR ('85). My advice would be to remove one wire / pintle (?) screw at a time and wrap a piece of masking tape to both and number them to match the wire number. This way you won't get confused when hooking things back up. Also take note of which wire connects to which plug on which bank (if you remove the wires from the plugs also). You'll see what I mean once you get started.

The small pintle / set screws that hold each wire to the cap can be gently unscrewed using a small screwdriver. These pintles vary in length, and they pierce the plug wire (you'll see the hole in the wire when you pull it out of the cap). That is why numbering them and keeping them straight is so important respective of their individual plug wire.

After cleaning the cap, and before reassembly, I'd recommend lightly and gently sanding the contacts in the cap and the pintle screws with a small piece of fine sand paper so as to clean off any surface corrosion / wear.

In my situation, I wasn't planning on going to all this effort -- but -- I needed to replace the worn rubber distributor cap boots with new ones, and figured I might as well check all that while at it, since the plug wires have to pull through the small holes in the rubber cap boots.

 

Good advice!

A few digital photos, some pieces of masking tape and as many notes as you can write about what goes where and how long the wires are supposed to be will save a lot of trouble later.

You can use a good aerosol "contact cleaner" to wash out the oil (you might want to replace the distributor seal as well).

Make sure that any flammable solvents inside the distributor cap is allowed to evaporate before you put it back on or BOOM! you'll have pieces of cap all over when you start it.

Silicone on the wires will make them easy to install.

 

I have made several sets of plug wires for TRs and have found that you should verify continuity of each wire with an ohm meter prior to installing everything back on the car. Check resistance from the terminal in the cap to the spark plug terminal at the end of the plug wire. The Lance-Screw doesn't always pierce the wire properly for a good connection. It's not unusual to have to remove a wire or two to reseat it in the cap and "re-pierce" it with the Lance-Screw. Be careful not to strip out the heads of the Lance-Screws. If you do other Italian cars like certain Fiats use them too. Be sure the center carbon button is in good shape too and that the little compression spring is okay.

You can buy new distributor caps for about $325 each (last price I knew anyway) from Frank Baker at Imported Auto Parts in Eatontown, N.J. They are considered "aftermarket" because although they are made by the original supplier to Ferrari....the Ferrari logo isn't on the caps. They are the exact same thing though.

 

Just replaced my TR distributor caps and www.allferrariparts.com had the best price by far -- $120 each (144637 and 144638). As Jeff described, "they are made by the original supplier to Ferrari....the Ferrari logo isn't on the caps", and they don't have the cylinder number stickers on them although they have the little raised circular area for the round number stickers (and, although allferrariparts tracks them by separte part numbers, they are the same part since there are no numbers.)

AFAIK, the stock left and right are the same cap except for the cylinder numbering.
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how long have these after market ones been around ? any data on how long they last ?

PS....why does ferrari have them listed as separate pieces that cannot be interchanged ?

 

Because the stock RH bank cap has 1-2-3-4-5-6-B labels and the stock LH bank cap has 7-8-9-10-11-12-B labels

I compared them to my stock caps and would say that they came out of the same mold (except without the MagnetiMarelli logo) and same materials - only obvious difference is that the end of the piercing screws is shaped a little differently (a "cone" rather than a "needle").

 

For 1/8th of the price i think we can live without the MM symbol and a cone end. Any long term tests on these ? they work exactly like the OEM product ? They do this for 308s, boxers as well ? That is a hell of a score for the price, i would only be alittle concerned if it melted to mess up and burn wires and damage the rotor inside.

 

These caps work fine, I had to buy new caps thanks to the POOR wire installation done by Automotive Restorations in Stratford CT(definitely not the place to bring your car for servicing) I have put about 6k miles on them already and there havent been any problems. Definitely be sure you push the wire all the way in before you screw them down. Another thing I noticed was that some of my spark plug extenders were cracked, this also may be worth looking into.

 

Without the MM symbol and the cyl numbers could cause you .025 points in a concourse event....While I try to keep the TR as original as possible, this is and will never be a GTO so driving it and being able to afford to keep it on the road is more important to me.

BTW, I was told by a Ferrari Mechanic a bit ago to check and change the rotors as when they wear, they cause more of a gap and wear the cap. If you change the rotor it will greatly lengthen the service life of the cap.

 

If you just want to clean the caps, you do not need to remove all the wires. Just make sure all are tight, then remove caps, turn them around so you can see and clean with an aerosal electronic parts cleaner and let dry, worked fine on mine.

 

I'd agree 100% with this concern when buying from a no-name eBay source, but you should give some weight to the source of these parts -- www.allferrariparts.com is a long-time, well-established, and well-known F part company that IMO would make it "right" if there ever was an unforseen problem.

I'd also like to say that their on-line parts lists is an excellent resource (if a part is listed) -- often there is extra useful information given in the parts description that none of the other on-line parts databases provides.

 

I think most of use arent entering the concours any time soon ...with that said at 1/8th of the price difference this is an excellent source. I wouldbe hard against putting something into the motor like a Volvo Thermostat to say $300.00 but this cap thing is fantastic. Only problem now, how do you tell you're mechanic you want these in instead?

 

Yeah, but, then you get the car not running right and they blame the part not there work We have all heard that story before.

 

Keep an eye onthe oil in the dist. cap. There is a seal around the cap that should prevent extrenal oil for seeping in but most don't have them. Another source is the rotor mounting shaft itself is rubber mounted to the endplug of the intake camshaft which is oil filled. The rubber can age and crack letting oil past. There is a lip type seal in the mounting flange of the dist. cap ($110 from ferrari which has a second lip sealing surface or $11 from the local bearing/seal store) which didn't fix the problem. The local dealer said the fix was engine out, the second dealer said engine out repair and the most senior mechanic at the second dealership said pickel fork and 20 minutes! Think of these things like old british sports cars, the red silicone sleeving can be installed over solid core ign wire (Mercedes uses it), the brass/copper contact points can be cleaned with sandpaper and a rubber boot covers the dist.cap (on my car) and the horse isn't visible. Treat the car to a new rotor. On my car, the wire fromthe coil to the cap had burned away inside the insulation, the carbon electrode had ground away 1/8 inch and the backing spring had broken in half......and the car still ran great! YMMV.

Jeff Pintler
89 348tb, 86tr

 

I just pulled off my two caps and found oil in the left bank cap. The problem is the oil seal pn #132452 $41.95 around the end of the intake cam. Its mounted in the distributor cap support, get a new gasket for the cap support when you order the oil seal. Simple job, don't even have to remove the roter, just rotate the plate and out it comes.
Good Luck

 

Becareful of these other caps that don't fit. Do they have aluminum contacts verses copper? I had the same issue with the Lamborghini Diablo I have. A Jag cap would fit, but due to the material used, it could get feed back and pop a computer. it wasn't worth the risk so I spent the extra $ for a Magnelli Marelli cap and rotor. Trust me I hated every minute of it, but I got my info from a very reliable source. Becareful on some of the short cuts. Also you may want to drill about5 1/8 pin holes on the caps to allow the Ozone gases out that the spark causes. This will help extend the life of these caps.