Cam and Crank Timing on Stock L28

[Supa Troopa]

I am trying to set the timing on the engine and I can not figure it out. I have read the factory service manual many times and I am uncertain if I have read it correctly.

 

I have the pin of the camshaft in the #1 slot on the inner set of numbers on the crank gear.

 

I have the bright link lined up with the #3 on the outer edge set of numbers of the crank gear.

 

I have the bright link lined up with the mark on the camshaft and also have #1 at TDC or 0 as indicated by the timing degree indicator.

 

I have included two picture I took to help explain where I am at. I have not adjusted the rockers yet on the head and it almost appears that at TDC, #1 intake valve is about to open. It might have to do with the fact that I have not adjusted them yet. Also this head is from another L28 block.

 

Also the two marks on the cam gear and the cam retaining cover.. ( look like - and v), mine right now looks like this -v. Literally the right end of the line touches the left part of the v.

 

I searched the forum and was unable to find a straight forward answer on a stock motor and I need some help. Thanks

 

 

[kolonelklink87]

my cam sprocket is 3-2(top)-1 from leftt to right at TDC but i'll wait for someone else to answer this one correctly... however - DONT adjust it or turn it or move is whatsoever untill you know what you're gonna do. DONT adjust the cam position untill the head is fully off the engine.

 

 

 

(correct me if im wrong guys but that cam looks 180* out?, my pin is at peak at TDC)

[FlatBlack]

I also had a hard time understanding the instructions in the FSM. Count how ever many links the FSM calls for [40?? I'm can't remember] from the notch on the crank and the notch on the cam gear.

[ozconnection]

 

 

(correct me if im wrong guys but that cam looks 180* out?, my pin is at peak at TDC)

 

Pete, you're correct, the cam IS 180 degrees outa position.

 

Easy fix, then when the cam is in the correct orientation, your little vee on the cam sprocket will line up with the notch on the thrust plate. That bit you'll find in your FSM.

 

I don't regularly count chain links. So long as your crank and cam are in the correct orientations, then your close. Factory cams can be adjusted using the factory notches, etc whereas aftermarket cams need to be properly dialed in using the cam card specs supplied with the cam. What do you have? If you need info on how to dial in an aftermarket grind, then you better search. There are some excellent threads on this topic, written by some really knowledgeable guys who have written it all in plain English.

 

Good luck, Cheers.

[Supa Troopa]

Thanks everyone. I will look into correcting this. This was my first post even though I have been lurking here for over a year. I usually find what I need through searching but this time I was in a jam.

 

So what I will do is pull the cam up, rotate it 180 so the pin is facing up and then in the end #2 on the outer edge will be at 12 o'clock correct? I am also assuming that my bright link will then be in the same location as it currently is but closer to #1 on the outer edge.

[ozconnection]

I think you'll be right with this...have you done this before? On an L series?

 

Verify that crank is at top dead centre on number one cylinder and leave it there.

Undo camshaft bolt, remove sprocket from camshaft.(if your engine is still exposed like in the pictures, its ok to proceed with this step. If not, you'll need to chock your chain so it doesn't fall down into the sump and your chain tensioner doesn't pop out of place.)

Loosen all of your rocker arms at the pedistals (sp) and remove rocker arms...keep them in order, don't mix 'em up.

rotate cam so dowel pin is at the top.

put rocker arms back in

put sprocket onto/under chain and pull that up to take up the slack on the chain and try and align the pin to the cam sprocket. Try number one hole if a new chain, number two or three if old. You may need to ride the chain over the sprocket a few links to get this right. You may also need to rock your cam back and forth a few degrees too to make everything line up. There is a hex boss on the cam halfway along its length for this purpose. A shifting spanner is pefect for this. If you're running out of hands, you can put the cam bolt back in to support the cam sprocket whilst your working the cam dowel into the sprocket. Just don't attempt to 'push' the sprocket onto the cam this way, you'll bend/break things for sure.

Then check the Vee on the sprocket line up with the notch/dash on the trust plate. Vee to the right of the notch...cam is advanced. Vee straight on the notch 0 deg. advanced.

 

That's as simple as I can make it man......good luck

[Supa Troopa]

My first time on an L series but not the first time I have set timing on a car, this one just confused the hell out of me. Thanks for the detailed instructions, definitely will make things easier. Thanks for your help.

[thrustnut]

Crank looks a little advanced also...at TDC on mine the key is to the left of the 1200 position, yours looks opposite. Might want to check that also, just pull your rocker arms first. Any one have a good way to verify crank TDC without putting the cover and pulley on? Other then watching the piston stroke, which can be a little inaccurate. For your numbering thing, if you use #1 hole, you LINE UP with #1 on the outside of the gear.

[HowlerMonkey]

When I find a "cam 180 degrees out" I just reclock the distributor shaft 180 degrees out and start driving right away.

[thrustnut]

Why not just fix it right?

[HowlerMonkey]

The only thing that is different if the cam is truly 180 degrees out is the distributor shaft.

 

If it is a couple of links on either side of 180 out or perfectly timed, there may be valve bending already.

 

Once the engine turns a few revolutions, the color of the links mean nothing.

 

My suggestion has far less risk of catastrophic cam mistiming and subsequent valve bending than "fixing it right".....especially when applying to someone with not a whole lot of experience.

[thrustnut]

So how would installing the dizzy 180 out and leaving the cam to engine timing be less catastrophic? If you remove the rocker arms (as stated before) thus releasing the valves into the head, rotating the cam to the correct position (which will not move the valves because there's no arms) ensuring the cam to engine timing is correct. Everything that has to do with the timing on this car is incorrect, you try to install the dizzy 180 out and start the engine and I'm pretty sure it will be toast. If your already in there, just do it right. Cutting corners will cost you money.

[ozconnection]

So how would installing the dizzy 180 out and leaving the cam to engine timing be less catastrophic? If you remove the rocker arms (as stated before) thus releasing the valves into the head, rotating the cam to the correct position (which will not move the valves because there's no arms) ensuring the cam to engine timing is correct. Everything that has to do with the timing on this car is incorrect, you try to install the dizzy 180 out and start the engine and I'm pretty sure it will be toast. If your already in there, just do it right. Cutting corners will cost you money.

 

That is absolutely correct Thrustnut. I would be taking this approach if this were my engine I was putting together

 

You can simply change the plug wires around on the dizzy cap, so that timing is effectively 180 degrees about face. But this is all screwy....just put it together right as you and I suggested too and remove all confusion. Simple.

 

And I'm sure Howlermonkey isnt suggesting dropping the dizzy spindle and clocking it 180 or dismembering the dizzy innards to clock that 180, are you? Don't go there man!

 

Cheers.

[HowlerMonkey]

So how would installing the dizzy 180 out and leaving the cam to engine timing be less catastrophic? If you remove the rocker arms (as stated before) thus releasing the valves into the head, rotating the cam to the correct position (which will not move the valves because there's no arms) ensuring the cam to engine timing is correct. Everything that has to do with the timing on this car is incorrect, you try to install the dizzy 180 out and start the engine and I'm pretty sure it will be toast. If your already in there, just do it right. Cutting corners will cost you money.

 

 

I guess you missed the part of my mentioning that it would be a solution ONLY if the cam/crank relationship was exactly 180 degrees out.

 

First thing to do is loosen greatly and/or pop out the rockers so that any movement of either cam or crank does not result in pistons hitting valves.

 

The second part of fixing this is identifying how far off the timing is and remembering whether the engine was turned while in this state of cam/crank index because you may have already experienced damage that needs to be addressed.

[thrustnut]

I didden't miss it...just trying to figure out why you would do it

[HowlerMonkey]

LOL.......you must also be an A&P.

 

OK.....I'll bite.....

 

How about when you chance upon a friend in the paddock at palm beach international raceway who's trying to get his SCCA improved touring 240z started after swapping in an engine someone else built because he popped his the day before.......and he only has 15 minutes to go until he has to be on the track?

 

That engine the rest of the season that way at the front of the pack and it took me all of 8 minutes to do it.

 

There's a time and a place to exercise options like that but you have to know of the options available in order to exercise them.

 

I was just adding an option to the thread.

[thrustnut]

I see how its an option, and someone with experience could pull it off, but when you install the cam upside down and are asking for help because your not sure what's wrong with it it would be best to stop and take it all apart and start over. If not because it would be "correct" but just to figure out what you did wrong and get it right for next time. I can just see someone installing the dizzy 180 out, the cam is almost 180 out and engine say 10 deg. ATDC...man, I would want a video! Anyway, yes I'm an A&P but I was a turbo-prop mechanic in the AF prior, and any time I did a job for the first time it was by the book...after you know what your doing you start cutting corners. I guess I still hold to that.