Topic: 121cu amc timing marks

[57stevej]

i need some help locating the timing marks on a 121 cu amc inline 4cyl ohc engine. the head has vw/audi markings on it but the valve cover has american motors on it. i have located the mark on the cam gear but don't know what to line it up with. i know where the mark is on the crank pully but they are about 2'. if anyone has any advice or knows where i can get a timing diagram plmk. thanks steve

[jamie1]

If you can me the CC and what car it is in,I might be able to help you. 121 cu tells me nothing.

[57stevej]

THE BEST I CAN FIND OUT IS THAT THIS ENGINE IS A 2L AND IT CAME IN A 79 AMC CONCORD. IT IS IN A 79 JEEP CJ NOW. IT IS AN OLD POSTAL SERVICE JEEP. I BOUGHT IT LIKE THIS AND HAVE NO INFO ON IT. THANKS, STEVE

[57stevej]

FOUND MORE INFO. MANUFACTURE DATE AUG-79, JEEP DJ-5G 8185981. ENGINE FAMILY V-T (AUTO TRANS) 121CID 4CYL, OHC.

[barrie1]

Welcome to the Forum 57steveJ. Make sure both are cleaned up and easy to read. Do you have a timing Gun handy as you will need one to check or reset the timing on this engine. Usually the marks are on the Harmonic balncer and the Degree plate behind the Balancer on the front of the motor. With the engine running you will see the degree's of timing with the light as the Balancer rotates past the Timing Degree plate.

[Sterling]

He's looking at the cam gear. That would indicate that he is looking for valve timing advice not ignition timing.

[tenpenny]

"If you can me the CC and what car it is in,I might be able to help you. 121 cu tells me nothing."

Well, you know it's an AMC..121 is cu inches...if that tells you nothing, then you don't know much....

I do believe that the AMC 121 was a vw/audi 2 liter engine built under license....try a jeep user's forum.....

(Message edited by tenpenny on February 06, 2005)

[Smainville]

This 4 cyl was built by Audi/Porsche for AMC, I had one in my 77 Gremlin and what a nightmare in the winter.  I recall very well that this bloody engine always "ping" adjusting the timing was difficult.  A google search does not come up with much, someone with a book would be ideal.

[articsteve]

I very well could have been built by Audi, but not Porsche.

Put the number 1 cylinder to TDC and see is you can find your other mark.  What repair have you down exactly?

I drove a Gremlin once with a 3 speed manual on the floor.  I think it was a 75.  It was like driving a tank.  It was a horrible vehicle.

(Message edited by articsteve on February 06, 2005)

[maritime_storm]

Newer ohc VW/Audi engines are setup as follows, being that VW/Audi engines do not tend to change in design much over time{why frig with what works right?}, this may be of help. There should be a dot on the cam gear it should line up with a corresponding dot on the head, there should be a groove in the cam at the back of the engine designed to have a bar fit in it to hold the cam from turning, when the 2 dots are lined a bar will fit in this groove. On the crank there should be similar markings to line up, when lined up insert timing belt, adjust tensioner and tighten, turn engine over by hand 1 full turn to verify that the marks are still lined properly. This is the very simplified method to do it written from memory on my 1991 1.6L/NA I had, but my service manual showed that the SOHC's at the time we're similar, yours may not be though so approach what I've written here with caution. Myslf I would have saved the trouble and put the 258 CID AMC I-6 in it, but you've decided on the four. Hope this is of help.

[Smainville]

Articsteve, here is a good read on this beast...

1977: This year was notable as the year the AMC Gremlin received its first major body restyling. The front of the car was shortened by 4 inches, with new front clip sheet metal, fenders, grill and bumper. The rear was restyled with a larger glass hatch and tail lights. The gasoline filler was moved behind the rear license plate. This eliminated the exterior location of the gasoline filler cap which at one time became a signature of the car with a heavy and ornate Gremlin symbol cast into the design of the filler cap (then as now, a high theft rate item causing a redesign shortly after the introduction of the car with a simpler and less ornate filler cap). Mechanically the biggest change was the availability of a new four cylinder engine based on the Porsche/Audi design. This engine featured an overhead camshaft and an aluminum cylinder head. Unfortunately this engine was underpowered and to some extent improperly geared to move the Gremlin and other AMC cars down the road well and proved to be an unpopular option. This was also the first year for the introduction of a new four speed transmission, an all synchronized Borg Warner designated the SR-4. It was available on both of the six cylinder engines. The 2.0L four got a lower power version called the HR-1.

http://www.amcyclopedia.org/tiki-index.php?page=1970-78+Gremlin

57Stevej, you might find your info from posters on that site, good luck.

(Message edited by smainville on February 07, 2005)

[articsteve]

Smainville; That was an interesting read.  So the Gremlin was around for 9 years.  That is just amazing.  The prices back then are also amazing.  The standard of living was better back then with respect to cars.  Super cheap gas, $25. per year insurance if you dared, 4 bucks for a license plate.

They really changed the Gremlin over that time period.  By and large the American Motors cars were pretty blah.  A high school buddy's parents had a Hornet and a Matador.  We used to go out and kill them.  As a kid I loved the AMX with a 390 I believe it had.

[barrie1]

The AMX did have a 390 among other engines. There is even a set of hi-performance heads which make these into one very fast car. There is a few of these left in my area and they are both done up with the 390's and special heads.

[57stevej]

thanks for all the info. we just kept working with it and got it running. if anyone runs across a repair manual for this engine plmn. thanks again, steve

[maritime_storm]

Chilton Manuals cover this car.