PDA

View Full Version : AMC 401 - Unknown Origins???


Bulltear Ad
Bulltear Ad

CJ-7-401
07-17-2007, 07:17 AM
I've got an AMC 401-V8 in my 1978 Jeep CJ-7. I know it is not the stock engine. For ease of replacing parts, I'm trying to identify it's origin.

Facts:

1) Has a "401" cast in the block on both side of engine
2) Has 2BBl carb, with a cast iron intake manifold, that looks to be stock.
3) Entire engine is painted "light red to orange" and probably could be stock color

4) metal tag on passenger valve cover shows "107 H22"

5) Oil dip stick & fuel pump on drivers side
6) All polution control items are plugged up.
7) Oil filter on pass side.

Does this engine have a serial # or id # anywhere on it to help identify?
I'm trying to determine the year and poss. the vehicle it came out of too.

Thanks for everyone's help on this ID project.

Jim

tufcj
07-17-2007, 07:39 AM
The 2BBl cast manifold and red color would indicate that it's out of an International Harvester originally. All AMC 401s were 4BBL and blue.

107H22 would indicate: 2BBL 304 engine built 07/22/1977, so I bet the valve cover tag is from your original engine.

1 = Year (1968 or 1977)
07 = Month (July)
H = 2BBL 304
22 = 22 day of the month

AMC sold 401 to International while they had a shortage of their own engines due to a strike at the foundry if I recall.

All parts except the dipstick are identical to AMC. SOME (not all) heads had the last digit or 2 digits of the year cast between the rockers on the end opposite the casting number. The year may also be cast in the lifter valley. It would require removing the valve covers or intake if you're really curious.

Bob
tufcj

J4GRAND
07-17-2007, 07:40 AM
Stock 401 2bbls were used in International Harvester pickups and Travelalls and were known as a V400 since IH had their own 401 which was completely different than the AMC 401. The only engine codes I could find for the 401 are from the Int'l Full Size Jeep Assoc. I think you may have valve covers from a 304 engine as those were the ones that had an H as the fourth digit in the engine code and were interchangeable with the 401.

CJ-7-401
07-17-2007, 08:45 AM
So here is where I am right now. I need a new fuel pump. From the above my 401 is definately not a "jeep" motor and must be a "IHC" engine that was bought from AMC -- All due to the 2BBL carb, providing it's stock.

PROBLEM: I bought a fuel pump for a 1978 Jeep Wagoneer w/ the 401 CI (towing package). The new fuel pump looks similar but smaller and the attachment flange has a different shape and the fuel line connections look different too. I did not yet take out the existing fuel pump, since it's still working, although it leaks. I dont want to take it out and disable the Jeep until I have a correct part to install and that one may be hard to find if the IHC part is different from the Jeep part.

What should I do?

1980_Cj7
07-17-2007, 09:08 AM
I have run into two different versions of fuel pumps for AMC V8's, one with the valves facing up, and one with the valves facing down. Both mount up and work fine, although some reworking of the fuel line is required.

If the mounting flange is the same, the arm is the same length and offset (yes, the cam on the cam isn't straight in from the fuel pump opening, IIRC it's offset to the rear), then it should work.

Dusty
07-17-2007, 10:50 AM
all the international engines share all the same hard parts with the amcs including the fuel pump. some parts superceed the older parts and thus we end up with having to rework things. going the route of the ihc fuel pump with a parts store made confound your problems.

to give you an example my cj needed a new fuel pump i took the cast in part number to 3 parts stores as well as the old pump all three had slightly different variations of my pump all with the same cast in part numbers on them.... same scenario as you with the fuel lines not close to where i needed em

CJ-7-401
07-17-2007, 12:32 PM
Okay, the mystery is getting solved. Went to the Carquest auto parts distr center store (huge inventory). I asked for a
fuel pump for a 1974 IHC Travelall w/ a 400V engine (6.6L) by AMC

They had it in stock!! Openned it up and it looks exactly like the one in my 401. So I guess mine is a IHC version on the AMC 401. Pictures of the two fuel pumps are shown below.

The big one is IHC 401 the smaller is the Jeep 401 (specifically for a 1978 Jeep Wagoneer)[/url]

1980_Cj7
07-17-2007, 01:16 PM
Bigger pump? I hope for your sake the size of the pump isn't directly related to how much gas you use, because our 401 with the smaller pump uses more gas than you can imagine, ha, ha. Why am I laughing? Maybe I'm delirious???

CJ-7-401
07-17-2007, 01:28 PM
Bigger pump? I hope for your sake the size of the pump isn't directly related to how much gas you use, because our 401 with the smaller pump uses more gas than you can imagine, ha, ha. Why am I laughing? Maybe I'm delirious???

Yeh, I hear that!!! Right now I'm at 9 mpg!! Can't get much worse. I'm running 4.10 gears. Maybe I should take it out of low range every once in a while for a change!!

Seriously, The "bowl body" on the IHC is 3.613"
On the Jeep it is only 2.725"

So according to your math, I'm on the way to 6-3/4 mpg!!

fuzz401
07-17-2007, 05:08 PM
9 mpg thats good I get maybe 1/2 to 3/4 gal to a 1/4 mile pass

1980_Cj7
07-17-2007, 05:54 PM
9 mpg thats good I get maybe 1/2 to 3/4 gal to a 1/4 mile pass

If I'm doing my math right, that translates to 1/3 mile per gallon!!! Holy (tire) smoke!!! No wonder you're trailering to the Jeep show. There aren't enuff gas stations between your house and the show, ha, ha.

Whatsamatta, didn't you read the EPA sticker before you bought that thang???

CJ-7-401
07-17-2007, 08:36 PM
Well it appears that I have the "odd ball" AMC 401 that was sold to IHC and they modified the engine with a 2 BBL carb & IM
painted it orange/red and put it in their "Travelall" in 1974 when the IHC motor plant was "on strike" and IHC ran out of their motor of choice a IH 392 V-8.

My mech. buddy showed me a vacuum line that goes from the 2BBL carb to the distr. He said the vacuum level changes the timing in the distributor to be advanced or retarded as the vacuum PSI changes, via throttle response.

This seems pretty complicated, does what he is saying make sense??

shawn
07-18-2007, 05:48 AM
Yes it makes sense. All Carbs have a "ported" vacuum port, usually used for dissy vacuum advance (but also for other things like egr, charcoal canister purge, and stuff like that).

Bulltear Ad