4Af timing belt off a tooth? - Toyota Nation Forum : Toyota Car and Truck Forums

bigbret · 01-23-2010, 08:43 PM

Hello all,

I am new to this site, I have just installed a new timing belt on a friends 89 corrolla. The original problem is that he did not pass California emissions testing. The ignition timing was set way off and the car failed the test because of it. I replaced the belt and lined up all the marks. I went to set the ignition timing and can not get it to 5 degrees. The distributor is maxed out on it's adjustment. I can get the timing to 15 degrees btdc, but then the dizzy runs out of adjustment room. I believe the cam timing is off a tooth or more? Any thoughts?

tomtom25 · 01-23-2010, 08:54 PM

Sounds like your timing is off a tooth. check your cam there should be a grove behind it to line it up with. Should just be able to just take the tensioner loose and turn it.

bigbret · 01-23-2010, 08:58 PM

Quote:

Originally Posted by tomtom25

Sounds like your timing is off a tooth. check your cam there should be a grove behind it to line it up with. Should just be able to just take the tensioner loose and turn it.

So I don't need to remove the whole belt just the top two belt covers. Then loosen tensioner and align the cam marks?

tomtom25 · 01-23-2010, 09:02 PM

no you shouldn't have to with those you can take your tensioner off and that should give you enough slack in it to get your cams in the right place. It saves from having to take it all apart.

bigbret · 01-23-2010, 09:09 PM

Well that is great I did not feel like taking this all apart in the rain tomorrow. So with the tensioner removed I will have the free play needed to readjust the cams. The groove you are reffering to is on the #1 cam bearing cap right or somewhere else? I referenced a hole in the exhaust cam pulley that lines up with the dot on the cam bearing cap. The intake cam gear also had a mark at 12:00. Does anyone have a picture they could post up?

tomtom25 · 01-23-2010, 09:13 PM

sorry i don't have any pics for you to look at but yeah it should give you room. the intake cam has a groove in it aswell at 12 but if not then it will have a hole in it that lines up with a groove behind it.

bigbret · 01-23-2010, 09:16 PM

Can I do this without removing the valve cover?

tomtom25 · 01-23-2010, 09:18 PM

no you shouldn't have to take the valve cover off.

Bitter · 01-23-2010, 09:28 PM

got the diag port jumpered to set timing?

bigbret · 01-23-2010, 09:36 PM

On the 4AF I thought you do not need to use the jumper! ( the car in carb'd)

eage8 · 01-24-2010, 01:27 AM

Quote:

Originally Posted by bigbret

On the 4AF I thought you do not need to use the jumper! ( the car in carb'd)

yeah, it has a vacuum advance on the distributor. I think you actually have to unhook a vacuum line and plug it...

and yes, you do have to take off the valve cover. you can't get the top timing belt cover off without taking that off.

Flashmn · 01-24-2010, 04:01 AM

Yeah on a 4A-F you need to take off the vacuum lines and plug them. then set it to the specified timing. If you dont do that, you'll never get it to 5degrees.

***SCT*** · 01-24-2010, 04:13 AM

Maybe this pic I posted in another thread would help. The two vacuum lines people are saying to disconnect and plug to do the timing.

And also, on 4AF motors (carbureted), you don't need to use a jump wire on the diagnostic plug (E1 to T). That's for 4AFE and maybe 4AGE, not 4AF.

Flashmn · 01-24-2010, 05:45 AM

Theres an error in the drawing,the green one comes off too.

EDIT: Correction, workshop manual says to take one off, but my other service manual says to take off both...And you're supposed to take off the one closer to the distributor housing (not the one in the drawing you made). I guess it really doesnt matter even if you take off both as the other one goes to the carb vacuum port, which means it doesnt see vacuum until you crack open the throttle plate.

Bitter · 01-24-2010, 08:42 AM

sorry, my mind put the E into 4AF automatically.