Anyone know what type of seal seats the dipstick tube into the block on a 1970 455? I can't seem to locate anything on any of the usual sites.

 

FWIW, have a look at the following write-up (fits both sbo & bbo).

Olds V8 Oil Pan Dipstick Replacement and Interchange

The actual dipstick he makes (Part Number DMR-9404) (note the flange in the dipstick where it meets the block) is noted below. From the previous article (above) you'll note the application of a dab of 100% Silicone.

https://dickmillerracing-com.3dcarts...r-SB_p_67.html

Is there such a seal located in the Oldsmobile 1970 PIM? EDIT: On second thought it may be indicated in the Engine Manual (I don't own it). I don't know - thought the above might be something for you to consider.

Additionally, in case the current dipstick broke, or still remains in the block, something to consider:

https://classicoldsmobile.com/forums...cation-102437/

 

The tube is a friction (compression) fit. You have to press (or tap, hammer, etc) the tube so the bulge goes into the block.

 

Thanks guys. Friction fit makes perfect sense. Explains why I couldn't find anything. Of course I made the mistake of already installing the header, starter, and inner fender well. I think I know what tomorrow holds for me now.

 

Kenneth is right about how the tube installs. The factory didn't use sealer.

And here is some additional additional information to make the job easier...
1. Use a 3/8" crowfoot wrench with a 3/8" extension to tap on the tube flange to seat it on the block.
2. You may need to lightly file the sealing bulges in the tube until your taps actually begin to move the tube into the block.

 

Thanks for the tip. I will try the crowsfoot wrench.

 

You don't have to remove anything. In fact, those items usually need to already be installed before the dipstick anyway. (well, the headers, certainly, which then usually means the starter as well)

 

Follow up to all of the great advice Tried my best with the crowfoot wrench and also the bolt in the top of the tube. I ended up using a dremel tool with a small grinding wheel. Took a slight amount of chrome off of the roll in the tube. It tapped right in with a bolt in the top. Thanks again for all of the helpful advice. Snug as can be and the dipstick reads accurately.