Author Topic: Fan spacer 3857041  (Read 2582 times)

hrlyfxdl

  • Member
  • ***
  • Posts: 166
    • View Profile
Fan spacer 3857041
« on: May 09, 2018, 07:07:53 PM »
I've searched through the forum and wasn't able to find any posts regarding this issue. I am trying to put back together correctly a 1968 350 for my car. I have gotten the spacer 3857041 and the correct 4 blade fan, along with the correct water pump and pulleys. My challenge is finding the right length OEM set of 4 bolts to hold this all together. I purchased a set on ebay and they seem to be about a 1/4" too long (they were our of a fan spacer 3927794). Both are pretty close to the same length according to the research report on CRG, but they won't work. They bottom out at the end of the threads on the water pump.
My question is, what length of bolt should I be looking for? I couldn't narrow it down by looking at the AIM for bolt 9425299 (couldn't find any size info) or is there a problem with my mount on the water pump that the end of the bolts aren't passing through to stick out a slight bit on the back side?

Thanks for any help. I posted the subject line as is so maybe easy to come up in a search later on for someone else. Shane
1968 Camaro SS 350 8L34677?
07A  E107  TR 712  U-U

5hane

bertfam

  • Hero Member
  • *****
  • Posts: 4492
    • View Profile
Re: Fan spacer 3857041
« Reply #1 on: May 09, 2018, 08:41:51 PM »
Shane, the 9425299 bolt was the replacement for the older 454891 bolt used in the late 1950's through early 1960's, and the specs for that bolt was 5/16-24 x 2.5". While it "should" be the same specs for the 9425299, there's no guarantee!

Ed



Petes L48

  • Hero Member
  • *****
  • Posts: 792
    • View Profile
Re: Fan spacer 3857041
« Reply #2 on: May 09, 2018, 09:04:13 PM »
I don't see the 9425299 bolts listed in the AMK catalog (which would have given dimensions).  Might be wrong, but I though the bolts/machine screws protruded though the threaded holes in the water pump flange?  Are you running out of threads on the bolt, or are the bolts not going through/out the back side of the flange?  Someone may have a set sitting in the garage which they can measure. 

hrlyfxdl

  • Member
  • ***
  • Posts: 166
    • View Profile
Re: Fan spacer 3857041
« Reply #3 on: May 09, 2018, 09:27:32 PM »
Ed, thanks for the updated info on the bolt numbers and size. I had gotten a set on ebay that measured 2.5" as they came from another spacer that was just a 1/16" difference than the one I have. They just went to the last thread on the flange and stopped, like I'd have had to wrench hard to push them past the back of the flange.

Pete, yeah the bolts hit the last thread on the flange and won't turn past it to stick out a bit in the back. If that is how they are supposed to be then the bolts I have should be fine that I purchased and I've got a problem then with the flange that I'll have to fix, probably retap, so the little extra bit of bolt protrudes through the back side of the flange. Just didn't want to go that far if I was missing something else.

Thanks guys, great help. Hope this solves it for someone else down the road. Cruise on!

1968 Camaro SS 350 8L34677?
07A  E107  TR 712  U-U

5hane

hrlyfxdl

  • Member
  • ***
  • Posts: 166
    • View Profile
Re: Fan spacer 3857041
« Reply #4 on: May 29, 2018, 01:47:56 PM »
Just an update, tapped out the holes on the flange on the water pump and worked like a charm. Bolts pass through without a hitch and stick out the back side about a 1/4". Thanks for the info and help guys.
1968 Camaro SS 350 8L34677?
07A  E107  TR 712  U-U

5hane