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Question about rear main seal

  • Thread starter Thread starter Yellowpnoy
  • Start date Start date Jan 6, 2007
Y

Yellowpnoy

New Member
Feb 6, 2006
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Jan 6, 2007
#1
  • Jan 6, 2007
  • #1
I just installed a rear main seal on my engine today and this is the first time i have done this. I used to hammers or anything like that and greased the seal to help slide on the crank. My question is, it seals around the crank nice and tight, but the outside edge of the seal has about an 1/8" gap between it and the block, is this normal for these motors ? I have a dart block if that makes any difference. Also, the seal spins with the crank. Thank for any help!

Anthony
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
3
58
Port Elgin, Ontario
Jan 6, 2007
#2
  • Jan 6, 2007
  • #2
if you have an 1/8 inch gap my guess is that the seal is the wrong size. You did it right though...a guy I work with just screwed a seal on a 98 Caravan by trying to but it on dry......it rolled the inner edge out
 
Y

Yellowpnoy

New Member
Feb 6, 2006
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Jan 6, 2007
#3
  • Jan 6, 2007
  • #3
Thanks roland, i couldnt beleive that was the right way that it went on. And i didnt think that that was right for it to spin on the crank. I will order one from jegs. Thanks!
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
3
58
Port Elgin, Ontario
Jan 6, 2007
#4
  • Jan 6, 2007
  • #4
make sure to let them know you have a dart block...Maby there is a difference. But Napa and most other parts stors should have them in stock
 

Mustang78

New Member
Feb 8, 2006
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Aberdeen, WA
Jan 6, 2007
#5
  • Jan 6, 2007
  • #5
dont grease the outer lip where it touches the block! also pack wheel bearing grease on the inside or the seal where the spring is, that will hold the spring in there when installing(if the spring comes out in your engine you need a new seal..and think of the internal damage....)gently tap the seal in usign a crisscross pattern as to not put it in sideways, and as you know fill that inner gap where it rides on the crank with assembly lube, good luck!

~Mark~

~Mark~
 
Y

Yellowpnoy

New Member
Feb 6, 2006
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Jan 7, 2007
#6
  • Jan 7, 2007
  • #6
I looked at the package the seal came in and there was a sticker over top of another sticker, i held it up to the light and i could read behind it that it said it was for a ford 232 V6 (3.8l)!! Now i know why it didnt fit, totally different part number than what i needed! I will be sure to pack it with bearing grease. Thanks for all your help!

Anthony
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Jan 7, 2007
#7
  • Jan 7, 2007
  • #7
The teflon seal is Fel-Pro BS40644 the rubber seal is Fel-Pro BS40620 and your local parts store should have them....

One thing I do on all the DART blocks I do it take the edge off the block where the seal slides on or it will slightly shave the outside of the seal when you tap it in. I have tired the grease method with good and bad results but the theory is dead nuts. I also put a very thin coating of Permatex on the outside of the seal before tapping it in, this helps it slide ina dn makes a leak free seal. I also like to leave it set up for a day if possible before starting the engine.

If your running a vac pump you can get a double lipped seal to help...
 
Y

Yellowpnoy

New Member
Feb 6, 2006
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Jan 7, 2007
#8
  • Jan 7, 2007
  • #8
Rick91gt, why didnt you post this sooner? LOL!! I went to put the seal in and it started shaving some of the rubber off the outside of the seal. I was going to do exactly what you said to do, take the edge off the block so it didnt tear the seal again. I will put some permatex on there to make sure its leak free. Thanks!! BTW, rick i should have said this was a 351 block, not a 302, i guess those part #'s are for a 302 block.

Anthony
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Jan 7, 2007
#9
  • Jan 7, 2007
  • #9
hehe...being an engine builder that is just part of standard block prep for me, it's something a lot of guys miss, same goes for the freeze plugs, cam plug.

yeah those were the 302 part numbers..the 351 uses BS40645 teflon or BS40592 for rubber
 
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