help with timing issue 5mge

[johnychavo]

Hey guys I'm assembling my 5mge to slap back into the cressida..and I've come across a weird timing issue..I set the crank to tdc then align the exhaust and intake cams.put the belt on and tension.ed it.did three turns by hand and then with the belt tight on the intake side I re tensioned it.then I noticed the rotors was pointing down.I was always under the assumption.it should be facing the number one plug.anyone in or near sacrameto wanna give me a hand so i don't screw this up haha

Crank at tdc...


Intake cam...


Exhaust cam...


Rotors...


Also trying to figure out how to align the cam pulleys correctly because the cam pulley has a few pin holes but there is only one pining the cams :/



Also have a set of cam pulleys that only have three holes..and e and t marks...


Anything I should watch out for? Any help would be greatly appreciated...

[ihateu3]

You are suppose to spin it twice and check, reason being is for every two rotations of your crank, the cams do one full rotation. So if you spun it three times, then even though your crank pulley lines up and cams, you are actually 180 degrees off on the crank (piston not at top dead center, exact opposite).

So basically, if you want to spin it more than 2 times, then spin it 4, 6, or 8 times to be in proper alignment. Just don't try to allign on odd number of spins like 1,3,5 or 7 or you will be 180 out

[Don L.]

Becareful swapping cam pulleys. Notice some of the pulleys use a round tooth belt and the earlier cars use a square tooth belt. Not interchangeable.

Don L.

[johnychavo]

Becareful swapping cam pulleys. Notice some of the pulleys use a round tooth belt and the earlier cars use a square tooth belt. Not interchangeable.

Don L.

Ok that makes sense becasue I have a set that looks odd compared to the one that were on my seized engine.how about the pin tho? Do i just use the middle hole on the cam pulley?

[johnychavo]

You are suppose to spin it twice and check, reason being is for every two rotations of your crank, the cams do one full rotation. So if you spun it three times, then even though your crank pulley lines up and cams, you are actually 180 degrees off on the crank (piston not at top dead center, exact opposite).

So basically, if you want to spin it more than 2 times, then spin it 4, 6, or 8 times to be in proper alignment. Just don't try to allign on odd number of spins like 1,3,5 or 7 or you will be 180 out

Yeah i knew all the just confused about lining up the cam pulleys now.there's 5 holes on each pulley can figure where to slide it on

[Don L.]

Yes, just use the middle hole on the pulley, be sure the pin is in the middle hole on the end of the cam.
The hole selected on the pulley and cam have to match, or timing is gonna be very off.

[Road Ripper]

Looks like you have an 82 engine, that uses the square tooth profile for the timing cogs. They had 2 more pin holes in them for additional cam settings. These engines were being raced back in the day, so the racing teams needed a quick way to adjust cam timing for the desired powerband. They are also used to set the cam timing properly after the belt stretches or the head has been milled down/block decked.

Here's a thread on how the cam timing affects the powerband, and how to adjust it for the desired powerband:
http://www.celicasupra.com/forums/sh...and-advantages

[johnychavo]

Looks like you have an 82 engine, that uses the square tooth profile for the timing cogs. They had 2 more pin holes in them for additional cam settings. These engines were being raced back in the day, so the racing teams needed a quick way to adjust cam timing for the desired powerband. They are also used to set the cam timing properly after the belt stretches or the head has been milled down/block decked.

Here's a thread on how the cam timing affects the powerband, and how to adjust it for the desired powerband:
http://www.celicasupra.com/forums/sh...and-advantages

Well my old motor that's seized is a 85 and the cam pulleys have 5 pin holes.the new motors pulleys have 3 pin holes.which pulleys should I use for the new motor?

[johnychavo]

Yes, just use the middle hole on the pulley, be sure the pin is in the middle hole on the end of the cam.
The hole selected on the pulley and cam have to match, or timing is gonna be very off.

That makes so much sense i appreciate the continued help and advice Don!

[johnychavo]

I see where I messed up the new motors pulleys only have three holes and are rounded and the old motors pulleys have 5 and are rounded.I guess my question is should i use the 3 hole or 5 hole on the new motor with the matched belt? Will the belt guide on the crank be rounded or square too?