Stripped oil drain plug - '79 620

[fizrat]

I went to change the oil on the RV before my return trip to BC, and got two unpleasant surprises: coolant leaking from the water pump and the oil drain plug turning and turning and turning and not going anywhere. I'm finishing replacing the water pump today (after O'Reillys initially gave me the wrong one - for A/C equipped vehicles), and then turning my attention to the oil plug.

 

First, any advice on removing a stripped drain plug?

 

Here are the replacement options as I see them:

 

1. Self-tapping oversized plug, if I can find it - can anyone tell me if these oil pans are made of soft aluminum so this will work?

2. Universal drain plug, something like this: http://www.pepboys.com/product/details/8328823/ - It looks like there would be quite a bit of bolt sticking out into the oil sump. Is there plenty of clearance for moving parts near the oil drain hole? Seems like there should be, but that's something I want to be certain about. Maybe someone can recommend one that works well on Datsuns?

3. Heli-coil/time-sert - don't have any experience with these, but have seen them mentioned - anyone done it on the oil pan?

 

I want to get back on the road ASAP, so I am leaning towards #2 as it would be the quickest and least prone to human error (I have the flu and am not operating at peak condition, exactly).

[HRH]

The pan is steel and it's not thick enough for any insert.  

A universal drain plug is nothing but an oil leak.  

 

Find the thread pitch, get an oversize one in that size.  And go to NAPA, will ya!? ;)  Going to the online site, it lists the stock drain plug as 16.4mm (retarded).  It's a little larger than 5/8".  Anyway, go to a competent parts store, have them get out the oil drain plug book and simple find an oil pan drain plug either in oversize.  (They won't list one for that application, trust me) OR find another size, buy a tap, put some vaseline or grease on the tap and tap the pan.  Then get the little bits of steel out with a magnet tool, whatever hasn't attached to the grease or vaseline.  Then install new larger size drain plug.  Done.

 

There is plenty of room for extra bolt in the oil pan.  It doesn't go near anything rotating.  Not unless you use a 3" bolt.

[Draker]

Time-serts are great for oil pans. Never done it in a Datto pan though.

[wayno]

Once you get the plug out, stick a dowel or something up in the hole to make sure the oil pickup assembly is not in the way, it's right there on my diesel pan, I can see it threw the hole and touch it, but they have two drain plugs on the diesel pans.

 

If you keep fighting this, trying to find a plug that will fit without results, just buy a new/good used oil pan.

[Silky_Johnson]

If you keep fighting this, trying to find a plug that will fit without results, just buy a new/good used oil pan.

 

I've got a nice pan that came off of a '77 620 that I don't need.  If you decide to just swap out the pan, I'd let it go for next to nothing plus whatever it costs to ship (Oregon to BC?).  Let me know if you want pictures.

[fizrat]

Thanks everyone.

 

I'm going to try HRH's plan and tap up to the next size (18, I guess) and install that size drain plug.

 

That is, once I get the plug out. It doesn't want to go anywhere. I've been pulling and turning and jiggling it with vise grips for an hour now and basically no progress. Any tricks?

 

Silky - I'll let you know if it comes to that - right now I am just looking to get back up to BC from LA ASAP... I was hoping to leave Monday before all this hit the fan!

[ggzilla]

The bolt is softer than the pan threads. Once you get the old bolt out, just put a new bolt in. The pan is probably fine.

 

Use vice-grips and pull firmly down when unscrewing it. Use screw driver for leverage pulling it down.

[Silky_Johnson]

Silky - I'll let you know if it comes to that - right now I am just looking to get back up to BC from LA ASAP... I was hoping to leave Monday before all this hit the fan!

 

LA to BC?  If you end up only limping home on a temporary fix, you can pick it up on your way through Portland for free -- that is, if that's the route your taking.  My work is right off of I-5, and my house is right off of I-205.

[fizrat]

Might just take you up on that oil pan offer. I'll let you know when I have a departure time and all.

 

No luck so far on getting that plug out. It is not backed out at all, the head is flush with the pan, so I can't get a screwdriver in to pry downward (tried wedging it in, but don't think it was doing a whole lot). Using all my strength to pull with vise grips and turn it ccw, but about all I can say is that now there is a little oil dripping and the plug wiggles slightly.

 

At this point I'm considering drilling it out. Ugh.

[fizrat]

All done - a friend came and drilled/ground out the old plug and retapped with 3/8" pipe thread, and using pipe plug as a drain plug. I strained the old oil and poured it back in a couple times to wash out any metal left from our activities. Fresh oil in the morning and hopefully good to go!