i think my cams are out 180 degrees???

[DeftAnesthetik]

as the title states i think i may have buggered up and installed my cams 180 degrees out, at top dead centre the lobes on #1 are pointed AWAY from each other, i was sure i was doing it right at the time but having gone back a re-read a few cam timing threads it seems to me that they should be pointed TOWARDS each other at #1 TDC. I never bothered to double check at the time and now am worried. Funny thing is it runs. I can see how this may be possible with both intake and exhaust being "upside down" for a lack of better description.

I finally managed to get the adjustable cam gears in and have been trying to get them dialed in but am having a heck of a time. (hence me going back and re-reading all i can about adjusting the cams) and have come to this conclusion.

any help here would be great. if i have them in properly it means i don't have to pull the top end apart AGAIN. But what MUST be done MUST be done. 1 month left to get this thing before the season starts.

[2jzhilux]

What motor is it?
There should be two dots on the cams that will line up with each other
They will be on the gears

[DeftAnesthetik]

sorry, 4age, non stock cams so i dont have the dimple, i checked the stock intake and it appears that i have them in correctly, as looking top down on the stock item with dimple up the lobes are to the left.

[roadsailing]

turn your motor over once and they will be pointing "away from each other"

[Steve M]

having gone back a re-read a few cam timing threads it seems to me that they should be pointed TOWARDS each other at #1 TDC.

That's interesting, I've only ever played with 18RGs and at TDC #1 they have the cyl. 1 lobes pointing AWAY from each other.

As roadsailing said, if you turn the motor to the next TDC position, you will find the cams are opposite but that would be TDC #4.

Sorry I can't be of much help here, I just thought that top point was interesting.

[merc-blue]

do you have a dial indiactor.
If not buy one
If you cant set TDC and Degree you cams


otherwise put the cam cover back on and give up!

[-GT-]

Goddamn, is this a joke?! Somebody listen to this man!;

turn your motor over once and they will be pointing "away from each other"

So if your intake cam is '180 out', and your exhaust cam is also '180 out'... (keep in mind we're talking a 'four stroke' engine)

... perhaps you've just set the cams at TDC for the intake stroke, as opposed to TDC for the exhaust stroke???

[DeftAnesthetik]

no, they are supposed to be pointed away from each other. in reality i did not need to ask. i am(or did at this point) degreeing with a wheel and dial indicator. thats why i needed to know. confusion was beacuse i had to roll the engine over 110 degrees before valves started lifting. as a note of a bit of (what i believe to be) misinformation out there, you roll the engine CLOCKWISE 110 degrees to adjust the EXHAUST and then COUNTERCLOCKWISE to adjust the INTAKE. most places i have read tell you to advance the engine for the intake and roll it back for the exhaust. i can tell you that this is incorrect. again unless MANY MANY things are wrong with my setup but if its out, i will keep it out since its running B-E-A-UTIFLY.

[-GT-]

No, they're not in upside down, or backwards. I cracked up a bit earlier because your statement about why you were concerned about your cam timing reminded me of a hilarious thread somewhere recently about a guy who thought his cams were in upside down, sorry if i was a bit blunt.

You stated you were concerned that your cams were timed '180 degrees out' because at no1 TDC the lobes were pointed away from each other, when you expected them to be pointing at each other (the lobes are at 9 and 3 o'clock, when you thought they should be at 3 and 9?)

Your cams turn one complete revolution for every two complete crankshaft revolutions. Therefore if you turn your crank over one complete revolution (ie around and back to no1 TDC) your cams will turn half of one revolution (ie go from 9 and 3 to 3 and 9), and voila, problem solved.

Or am i completely misunderstanding your problem?

[DeftAnesthetik]

stock cam timing at #1 TDC intake stroke all match marks lined up cam lobes on #1 should be pointed AWAY from each other. I know i can make them point together by rotating the crank 360 but then the knock pins on the cams are not lined up to the marks on the.... (head/camcover/plate???) as described in any 4age manual. Really it just looked funny to me, but this is my first attempt at degreeing an engine. its all a learning experience, i am a free-form logical thinker, if whatever it is i have mantled as my current project, works or doesnt work, i have to question why and expand my understanding of the universe. unfortunately sometimes i need help wrapping my head around stuff and thats where the forums come in. i know sometimes i get on here and ask what could be considered "stupid" questions but by far i am not the worst perpetrator of such posts, i will spend the time to search for relevant answers and if they exist i dont post a new question. and hopefully get an answer that works for me and maybe helps out some others. there i go rambling again....

[-GT-]

Hey not at all dude, i understand. I realised i could've been more constructive as my first post was having a bit of a laugh to myself more than anyone, but i think even once i was trying to help i was still being pretty oblique about the point i was trying to make, which is this;

what dictates that the engine as on the intake stroke when at TDC, rather than the exhaust? It's not the marks. It's the position of the cams.

You may very well have got the cams 180 degree out from the marks but the engine, or cams, or whatever has no idea and gives no fark for where the marks are, the engine will still run perfectly, and nothing is wrong in the setup, apart from perhaps a couple of marks used for setup purposes and have no impact on the actual running of the engine.

Whether you're on the first crank rotation of the cycle or the second is only determined by where the cams are in their rotation - you may have been trying to configure the drivetrain in no1 tdc intake but if they're 180 out that position just became no1 tdc exhaust.

[-GT-]

stock cam timing at #1 TDC intake stroke all match marks lined up cam lobes on #1 should be pointed AWAY from each other.

Another way to try and convey what i'm trying to say; it's not the intake stroke because the marks are all lined up, it's the intake stroke because the lobes are pointing away from each other.

If they're not pointing away from each other but are actually pointing towards each other, it's not the intake stroke, it's the exhaust stroke, and your marks are 180 out.

[DeftAnesthetik]

I have/had them in correctly. Its all good. Thanks

[roadkill]

Hi,

For future refernce as long as you have TDC on cyl 1 and the lobes on the cam for cyl 1 are "pointing" in opposing directions then they should be correct. It is only really your timing that will be out by 180 deg (ie trying to spark at top of exhaust, not top of compression) and this will be heaps easier/quicker to fix!! If one come was out by 180 deg you would probably have lots of bent valves!!!


bEn

[DeftAnesthetik]

OK, OK, OK.... I figured out why I was all messed up. here is the explanation for those who are/maybe in the future struggling with timing their cams.

Initially you will need to set the timing belt as described in the BGB (or any other 4age manual) Knock pin for intake at nearly 12 o'clock and exhaust at nearly 6 o'clock. So the index marks on the (again i want to say cam cover) on the front of the head line up with the cam gears. Looking at the cams, you will see that the lobes are facing AWAY from each other on #1 cylinder. to set your cams to 110-110 or 100-100 whatever the case may be you need to rotate the crank 360 degrees to bring #1 back to TDC. now you will notice the lobes on the cams are facing TOWARDS each other. its from here you install your degree wheel and dial gauge set a pointer at 0 degrees. Rotate 110/100 forward, and adjust intake for MAX lift, rotate 110/100 backward, and adjust exhaust for MAX lift.

My confusion cam from reading Billzilla's site here (http://www.billzilla.org/4agmods2.htm)
i was reading....... "With the engine at Top Dead Centre (TDC) #1 or #4 cylinder, and what you are looking for is to have the inlet cam lobes for #1 cylinder just starting to open"

when i hear/read the word "engine" i think of the complete assembled package. had i read "block, pistons or bottom-end" it would have been less confusing.