308 Oil drain plug

I noticed that noone responed to you thread so I'll give you an opinion not an answer. My 308 appearently had the drain plug stripped because someone nicely welded a small al plate on the pan and threaded it however it is not the same size as the other plugs. I doubt if the factory would use a heli-coil. If the 1/2" plug is working maybe it's best leaving will enough alone. I don't know if there is a heli-coil with the correct dimensions to fit 1/2" and the OEM plug. I did want to tell you I saw a repair kit on Ebay a while back to fix a stripped plug hole. I checked and there were none up for auction currently. At least you know that there is such a thing but you had to drill out the drain hole to use this repair plug. Good luck.

 

Hello from Germany,

actually on the later engines there is a helicoil for the oil drain plugs. Both on the transmission and engine pan.
The Ferrari part no. is 112254 and I have one here.

Problem is, that only heaven knows where to get the correct helicoil tap and tool for fitting this insert.

Another example for helicoils on these engines is the rear cambelt cover. On earlier engines they used studs and nuts. On these cylinder heads there are no helicoils for the relevant studs.
On the later engines they used bolts to attach the cambelt cover. And on these cylinder heads there are helicoils.

Best Regards

Martin

 

As a long time owner, I learned that sometimes it is better to leave well enough alone. If it is not leaking, leave it alone. If that changes, then fix it.

 

I had a similar problem in my 330. I made a fitting that screwed into the 1/2" pipe threads and was tapped for the proper plug on the inside. See http://www.parrotbyte.com/kbc/ferrari/OilDrainPlug.htm for details.

 

Hi Martin
What you said about the helicoil makes perfect sense. The aluminum might be too soft to hold up with any torque and something like an oil drain plug that is changed often would tend to wear the aluminum threads out. You said that later engines had helicoils on the drain plugs so what did the earlier ones do? Hope you had a nice Holidays.

 

There is a 22x1.5 mm Heli-coil inserted in both pans, they do wear out mostly do to over tightening the plug. Fastenal, Tacoma Screw and others can order a 22x1.5 mm Heli-coil set, but its 3 weeks and around $250.00 (I’m sure they make it to order, no demand) you still will have to provide the drill. The better fix is using a steel bung plug insert.

 

There is a repair plug on ebay now that may work for you. Look at ebay auction #300068214936 and the ends on Jan 14. Good luck.

 

Hello from Germany,

overtightening the plug can not only lead to a stripped thread, but also to radial cracks around the hole.
I had this worst case years ago. Maybe some previous owner or mechanic - or even me - was more used to cast iron machines than italian aluminium artwork.
In that case, nothing but a new pan helped. The old one now serves well as my workshop ashtray.

Best Regards

Martin

 

The pan can be repaired, but keep in mind “IF” you heli arc the pan, it “WILL” warp. Not only will it warp like a banana, but depending on how much repair / weld it needs, it may also shrink. The pan can be annealed and warped back into its flat state, but it takes a person with some metallurgy knowledge and a lot of patience (the pan baffle risers hold the heat and after annealing, will warp the pan again upon cooling). If you attempt to heli arc a crack, first drill a 1/8” hole on both ends to prevent the crack from spreading.

 

thanks for this. Since I have a drysump car, the oil pan has no baffles. It's just a flat cover. Still expensive but not that much like the wetsump pan.
And removal is easy. Just undoing all nuts but no removal of the dipstick tube and temperatur sender, which are both located in the oil tank in my case.

Best Regards from Germany

Martin
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Martin, your one of the lucky ones with the easier fix. If you pan ever did need welding, it certainly would be easier to flatten verses the wet sump style with baffles. It looks like you could re-machine one from billet if needed.

 

Timesert appears to make the 22x1.5mm kits

http://www.timesert.com/html/mtrcsert.html

These are said to be more durable than a helicoil.

 

there is one on eBay, here is the link:

http://cgi.ebay.com/ebaymotors/Ferrari-308-328-Mondial-Engine-Trans-Bung-Plug-Repair_W0QQitemZ300068214936QQihZ020QQcategoryZ6755QQrdZ1QQcmdZViewItem


stephen