Another 1967/ac bb question

[Kenneth B.]

From whet I have read all BB 67'S had the short dip stick like my 435 but my 67/air BB has a long tube. If it had the short one it would be hard to get it out because of the AC hoses, Is there a chance that the AC Corvettes had the longer tubes/stick or should I change to the short one?

[John H.]

Re: Another 1967/ac bb question

From whet I have read all BB 67'S had the short dip stick like my 435 but my 67/air BB has a long tube. If it had the short one it would be hard to get it out because of the AC hoses, Is there a chance that the AC Corvettes had the longer tubes/stick or should I change to the short one?

Ken -

I've never seen anything in the Assembly Manual (either in the C60 or L36 sections) that calls out a unique dipstick and tube with air conditioning; I'm accustomed to seeing the top of the dipstick tube about 1-1/2" above its attaching bracket to the exhaust manifold bolt. I think passenger cars used a longer tube (and different dipstick).

The revision block for the '67 BB dipstick (L36, sheet A6) calls out dipstick #3860316 and #3862732 tube on early cars (same parts used in '65 and '66), which changed to #3925520 dipstick and #3870324 tube; those revisions were made on the sheet on 2-8-67 (tube) and 3-5-67 (dipstick), but I don't know the actual implementation date on the line, or the dimensions of either one - maybe Joe L. has the dimensions.

[Joe L.]

Re: Another 1967/ac bb question

Ken -

I've never seen anything in the Assembly Manual (either in the C60 or L36 sections) that calls out a unique dipstick and tube with air conditioning; I'm accustomed to seeing the top of the dipstick tube about 1-1/2" above its attaching bracket to the exhaust manifold bolt. I think passenger cars used a longer tube (and different dipstick).



The revision block for the '67 BB dipstick (L36, sheet A6) calls out dipstick #3860316 and #3862732 tube on early cars (same parts used in '65 and '66), which changed to #3925520 dipstick and #3870324 tube; those revisions were made on the sheet on 2-8-67 (tube) and 3-5-67 (dipstick), but I don't know the actual implementation date on the line, or the dimensions of either one - maybe Joe L. has the dimensions.

John-----


I don't have the dimensions on the 3862732 and 3870324 tubes. However, I believe they were either the same length or, at most, very slightly different. For one thing, the 3870324 tube became SERVICE for 1965-66 Corvette big blocks and could be used with the original dipsticks. For another thing, there's very little difference in the GM #3860316 and GM #3925520 dipsticks. The 3860316 and 3925520 both have a dimension from the seat to the "full" mark of 17-13/32". The 3860316 has a dimension from the seat to the "add" mark of 18-1/8" whereas the 3925520 has a dimension of 18-1/2". I think the change was probably made because of some calibration problem observed with the 3860316 dipstick.

The "long" dipstick and tube came into use for the 1970 model year. These parts also became SERVICE for 1965-69 Corvette big blocks but only when used as a set. Notwithstanding the difficulty of accessing the dipstick on cars with C-60, I do not believe that any 1965-69 big block was ever ORIGINALLY equipped with a "long" dipstick and tube, although I wouldn't absolutely rule it out for late 1969's, C-60-equipped or not.

[Kenneth B.]

Re: Another 1967/ac bb question

THANKS That is what I thought. I did notice when I put the short one in It was almost under the 2 AC hoses.