International Full Size Jeep Association
Home Forums Reader's Rigs Tech Library Trail Stories FSJ-List
International Full Size Jeep Association  

Go Back   International Full Size Jeep Association > Tire Kickin' > General FSJ Discussion

Reply
 
Thread Tools Search this Thread Display Modes
  #21  
Old 03-28-2020, 09:51 PM
spduffee's Avatar
spduffee spduffee is offline
232 I6
 
Join Date: Jul 20, 2017
Location: Washington (WA)
Posts: 33
[quote=Ristow]
i'd throw a new fr118 flexplate and not worry about /QUOTE]

So I checked the Pioneer website and looked at the FRA 118, applications, and it covers the Matador 304, various CJs with 304s, but also my Wagoneer with a 360. Just to confirm I searched by vehicle: 1986 Grand Wagoneer 5.9 V8. Result: FRA 118... If that's what is already on there why worry about it? I am about to yank the 360 out, so we'll see.
Reply With Quote
  #22  
Old 03-29-2020, 03:19 AM
Carnuck's Avatar
Carnuck Carnuck is offline
 
Join Date: Feb 12, 2011
Location: Gold Bar, WA
Posts: 6,419
The little sheet of paper inside the FRA118 box used to say that it needed to be match balanced to the 304 because it came with the bigger weight for the 360. I drove 304s with a 360 flexplate and the resultant vibration was enough to wear your teeth down. I recall filing off enough weight to account for a US quarter from the balance blob.
Again, the crankshaft is shared between 360 and 304 along with the connecting rods (707 cast with V8 offset of the big ends) The difference of the balancing comes from the different sizes and therefore weights of each of pistons.
The harmonic balancer is even more important than the flexplate. There are two later model balancers. 3 bolt (like Chev) for Motorola alternator accessories or 4 bolt with Delco alternator around ‘74 and up. I was lucky enough to have both styles of belt pulleys kicking around.

There is a reason AMC had 2 different flexplate numbers for the same years of 304 and 360.
__________________
Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental.
Reply With Quote
  #23  
Old 03-29-2020, 07:34 AM
SC/397's Avatar
SC/397 SC/397 is offline
Administrator
 
Join Date: Feb 01, 2010
Location: Michigan
Posts: 863
[quote=spduffee]
Quote:
Originally Posted by Ristow
i'd throw a new fr118 flexplate and not worry about /QUOTE]

So I checked the Pioneer website and looked at the FRA 118, applications, and it covers the Matador 304, various CJs with 304s, but also my Wagoneer with a 360. Just to confirm I searched by vehicle: 1986 Grand Wagoneer 5.9 V8. Result: FRA 118... If that's what is already on there why worry about it? I am about to yank the 360 out, so we'll see.




Because it may vibrate. You might get lucky it you won't notice it.

FYI, The weight on a 304 flex plate is 1" x 2 3/4".

The weight on a 360 is 1" x 3 1/4". The factory also drilled holes in them here and there to finally balance it out. You might consider doing what Carnuck did and trim the weight on the 360 flex plate down to the 304 size.
Reply With Quote
  #24  
Old 03-29-2020, 09:57 AM
Mephistopoles's Avatar
Mephistopoles Mephistopoles is offline
232 I6
 
Join Date: Jan 21, 2006
Location: SW WA
Posts: 92
Quote:
Originally Posted by SC/397
Believe it or not..
IMG_2941 by Rick Jones, on Flickr
IMG_2940 by Rick Jones, on Flickr




This gives a partial explanation as to why factory engines ran for over 100K miles, while home rebuilt engines often barely make it out of the driveway. Along with a few other factors.
__________________
78 Wag 401/TH 400
78 J-10 401/TH 400
69 AMC Rebel 2Dr/HT 401/TH 400
Reply With Quote
  #25  
Old 03-29-2020, 10:00 AM
Carnuck's Avatar
Carnuck Carnuck is offline
 
Join Date: Feb 12, 2011
Location: Gold Bar, WA
Posts: 6,419
The only rebuilt ANC motors I had trouble with were due to poor quality Badger pistons from the ‘80s and ‘90S that weren’t up to handling ping or the motors had been massively overheated.
__________________
Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental.
Reply With Quote
  #26  
Old 03-29-2020, 10:21 AM
spduffee's Avatar
spduffee spduffee is offline
232 I6
 
Join Date: Jul 20, 2017
Location: Washington (WA)
Posts: 33
Ok, I understand now what needs to be done. Thanks once again for clarifying about the FRA118.

Harmonic balancer: If one is presently on the engine, I don't need to worry about that, correct? I only ask because it was brought up 2 or 3 times - just making sure.

Btw, I started looking into the 304 and I swear it looks like it was just rebuilt. The stamping on the heads (3216086-2) tell me they are a '74 304. Still can't find why there is a big GM stamped there, too. But looks good so far.

Shawn
Reply With Quote
  #27  
Old 03-29-2020, 03:21 PM
SC/397's Avatar
SC/397 SC/397 is offline
Administrator
 
Join Date: Feb 01, 2010
Location: Michigan
Posts: 863
Harmonic balancer: If one is presently on the engine, I don't need to worry about that, correct?
Correct. This shows a picture of it if you can see past the photosucket crap.
http://theamcforum.com/forum/amc-har...opic38898.html
Reply With Quote
  #28  
Old 03-29-2020, 04:29 PM
Carnuck's Avatar
Carnuck Carnuck is offline
 
Join Date: Feb 12, 2011
Location: Gold Bar, WA
Posts: 6,419
1973 and later 4 bolt Dampers. 304, 360, 401.

The off-set weight goes 90 degrees around on a 304 (both 3 & 4 bolt)

The off-set weight goes 240 degrees around on a 360 (both 3 & 4 bolt)

The off-set weight goes 180 degrees on a 1971-1972 401. (3-bolt)
The off-set weight goes 240 degrees on a 1973 and later 401 (4-bolt)

According to this, 304 and 360 can’t use the same balancer but the flexplate has the weight in same position but different offsets according to engine size. I know the TH400 flexplates have a “moustache” of weight that is obvious compared to each other.

The biggest question now, is this a 3 or 4 bolt balancer pulley setup.
__________________
Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
TH400 to 727... pilot bushing??? lincoln72 General FSJ Tech 8 03-14-2019 02:26 PM
AMC 727 to Dodge 727 adapter 72jeeperjoe General FSJ Tech 5 07-25-2018 10:04 AM
Chrysler (not AMC) 727 to NP229 ottocycle General FSJ Tech 1 08-14-2010 05:16 PM
727 w/ QT compatible RamJetFSJ General FSJ Tech 2 01-10-2002 09:14 AM


All times are GMT -6. The time now is 11:24 AM.


Powered by vBulletin Version 3.5.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
corner corner