Timing

[Cav Trooper]

I am in the process of finding out what if any problems I have with my M37 engine. I had broached the subject here a little while back and got good feedback about compression testing etc. I haven't check the compression yet but I was going to check timing over the weekend since I had a extra hand to help. First, the adapter I bought at the Indiana MVPA show does not fit, although I was told it would. I rigged up an extension so that I could use my inductive timing light, got that to work.. Next problem, I noticed the front pulley was wobling some so before I started all of this, I bought a new one, looked like a PIA to replace. I did notice that there is a dimple on the back side of the pulley that roughly coincides with the timing marks since I also noticed that the 6 holes look symetical and it would be a bxxxch to find mechanical timing on the crank to pulley. Now for the kick in the xxx. When I tried to check the timing, the light flashes but the timing is no where near the pulley timing reference marks. I figured whenever the person who rebuilt the engine, if they did, didn't bother to align the pulley with the crank properly. Since I had to drain the radiator to install my heater also, I removed the radiator and found out that there is no pin or other indication on the crankshaft to indicate TDC or any other reference with the pulley. Is there an easy way to find the mechanical timing on the crank to pulley? My first thought is that I will have to remove No. 1 plug and find TDC and reference from there.

Regards,

Cav Trooper

[rixm37]

OK try this. Get #1 on the compression stroke by removing the spark plug and putting your thumb over the hole and bump the starter until you feel the pressure. OK then remove the small pipe plug over #6 and put a stick down the hole, a skewer stick works great.The hole is over the #6 piston. #1 and #6 are on the same swing, so you can find TDC by moving the engine back and forth with a wrench on the front pulley nut or sometimes just pulling on the fan and and the belt. mark the stick and you can find TDC when it sticks out of the cylinder the farthest. Then look at where you are on the pulley. Hope this helps.

[powerwagontim]

Cav Trooper,
The 6 holes on your main pulley may look symetrical, but they are not. They will only line up one way, so the timing marks are in the right place in relation to your crank.
Tim

[SOTVEN]

Cav Trooper,
The 6 holes on your main pulley may look symetrical, but they are not. They will only line up one way, so the timing marks are in the right place in relation to your crank.
Tim

I WOULD ALSO ASSUME THAT THOSE SIX HOLES WOULD NOT BE SYMETRICAL, BUT IN MY M THE PULLEY WAS 180 DEGREES OFF FROM THE TDC FOR #1 AND #6. APPARENTLY SOME MAINTENANCE GUY IN YHE GREEK ARMY MADE THEM SYMETRICAL WITH AN AIR WRENCH LOL.

CAVTROOPER, LIKE AFOREMENTIONED, FIND THE COMPRESION STROKE ON #1 AND THEN REMOVE THE BOLT DIRECTLY OVER THE #6. IMHO, AS OPPOSED TO A STICK, TAKE A PIECE OF STRAIGT COPPER WIRE, AND TWIST THE REAR END OF IT TO A LOOP SO IT DOES NOT FALL THROUGH THE HOLE IN ANY WAY, AND BY TURNING THE BELT, MAIN PULEY OR STARTER FIND THE EXACT TDC FOR #6 AND HENCE #1. TURNING WILL BE EASIER IF YOU REMOVE ALL SPARKPLUGS FIRST. ONCE TDC IS FOUND, THEN TAKE THE COVER OFF YOUR DISTRIBUTOR. IF YOUR OIL PUMP/DISTRIBUTOR SETUP WAS PUT IN CORRECTLY, THEN YOUR DIST SHOULD BE POINTING ROUGHLY AT "7 OCLOCK" (THE ENGINE BLOCK BEING 12). IF ALRIGHT SO FAR, THEN MOUNT YOUR PULLEY WITH THE MARKINGS UPWARDS AND UNDERNEATH THE TIMING POINTER. REASEMBLE EVERYTHING AND FIRE UP. IT SHOULD START OR AT LEAST "COUGH" IT IS A MATTER OF FINETUNING OF THE TIMING AFTER THAT. AS FAR AS I REMEMBER THE MANUAL SAYS 2 DEGREES BTDC, BUT SOME PEOPLE HERE ADVISED 4 DEGREES. GOOD LUCK FRIEND.

[cuz]

2 ATDC

[Rick C]

ok, question......when standing at teh radiator looking down.... which side is after and which is before TDC

[cuz]

Turn the fan in it's correct cooling direction and you'll see right away which comes first.

[Lifer]

ok, question......when standing at teh radiator looking down.... which side is after and which is before TDC

I can't believe someone actually asked that question!

Still, we all have to start somewhere, I guess. If you truly didn't know, it was not a dumb question. It just indicates that you're starting with more of a handicap than most of us.

[MSeriesRebuild]

The correct timing is 4 degrees BEFORE TDC. 2 degrees after is in the manual, however it is totally wrong. After TDC timing is too late, setting at this set will always cause a very poor running and performing engine.

The marks on the pulley are actually self explanitory, the crankshaft turns clockwise, thus the marks on the right side of the TDC mark as viewed looking down on the pulley are before TDC.

The pulley only mounts on the crank in 1 position, it can't be installed out of time.

[Rick C]

LOL, I knew the answer...was being a wiseass... But figured with the turrnover in the room maybe go basic on the timing issue. BTW mine doesn't run well on either 2 or the 4 setting....it pings like crazy on hills at those...

[cuz]

I know the manuals are horse crap for the gods of the G741 but at least 12 of them give you the option for the 230 six from 2 BTDC to 6 ATDC. I set 2 ATDC static and check her with the timing light and a vacuum gage and take it where it does best. There can always be a better setting but I don't call the initial factory spec settings wrong simply because I found something that works better. If I find something that works better I'll pass it along as an aside.

[MSeriesRebuild]

Not trying to be a God Cuz, nor a book only guy that seems to be your style in all areas. The thing is this, talk to all the master mechanics you know in various fields. I think you will find that they all say any timing after TDC is not a good setting. Fuel quality and elevation will cause some variation in an optimum setting, however not a lot. Most agree the 2* ATDC in the book was a mistake and was meant to be 2* BTDC. There are many mistakes in the manuals, some are more obvious than others, this one is pretty obvious with all whom I've ever discussed it with. No I'm not trying to start an arguement, just passing along the facts

[cuz]

or a book only guy that seems to be your style in all areas.

This is argumentative in any circle. You still are enveloped in the god thing.

In these forums normally less than 20% of the members are experienced mechanics and even less about 5 to 10% are professional mechanics. Therefore one should shed the tenured professor's coat and demeanor and try to get back to basics. In most cases the basics start with the book. I've been involved in training mechanics both classroom and OJT for many years and you start with the book, then add some personal experience, then add the shortcuts and by then they have the confidence to explore even further on their own.

You can think a spec is wrong in any book. Can you prove it is wrong? Can you explain why the +2 to -6 numbers managed to stay in all the Mopar and Army pubs dating from 1935 thru present? Have you even researched it this far?

[M37UK]

"In these forums normally less than 20% of the members are experienced mechanics"

Damn, my cover's blown .......................

[MSeriesRebuild]

or a book only guy that seems to be your style in all areas.

This is argumentative in any circle. You still are enveloped in the god thing.

In these forums normally less than 20% of the members are experienced mechanics and even less about 5 to 10% are professional mechanics. Therefore one should shed the tenured professor's coat and demeanor and try to get back to basics. In most cases the basics start with the book. I've been involved in training mechanics both classroom and OJT for many years and you start with the book, then add some personal experience, then add the shortcuts and by then they have the confidence to explore even further on their own.

You can think a spec is wrong in any book. Can you prove it is wrong? Can you explain why the +2 to -6 numbers managed to stay in all the Mopar and Army pubs dating from 1935 thru present? Have you even researched it this far?

This is getting rather pathetic.

Hey Cuz, why in the world would I need to spend time researching something that I already know doesn't work; I have more productive stuff to spend time on.

Got a challenge for you; set up a 230 at -6 as a research project of your own; then post a truthful analysis of how well you are impressed with it's performance; ask me then if I can prove it's wrong if you still feel the need. I know it would hurt your feelings to even consider anything I would suggest, with that said my only suggestion to you is to have a couple of spare batteries on the side as a 24 volt jumper; with timing set up on -6, you may have to do some extended cranking before it starts.

I have no idea and won't even ask where you came up with the stats you posted here about less than 20% of forum participants being experienced mechanics. Neither do I have any idea about the mechanical skills of most who post here; however, Cuz you have over time managed to convince me that most likely you fall into that less than 20% catagory that you describe.