Slant Six Forum :: Timing out of whack

I guess maybe I am jumping the gun than but this is how the timing marks should appear according to my FSM

Quote:

I guess maybe I am jumping the gun than but this is how the timing marks should appear according to my FSM

And if you make one more revolution of the crank, they will line up that way!
Nothing wrong there.

Edit: Some stock timing sets don't time on TDC compression. As long as the dots line up your good, that might be tdc on intake stroke and not compression stroke. if you get my point.

It's difficult to see what is wrong. Perhaps parallax based on the angle of the camera is hiding it from me. (Your date stamps are September of 2007 by the way.)

Are the dots lined up through the centerline of the crankshaft and cam? If so, then the timing set is lined up correctly. The next step is to degree the cam. If it was one of the OEM replacement cams, it is most likely to have events that coincide with the MP244. That is the most common for a mechanical replacement over the counter.
To degree the cam may require a different timing set. The one you have is the slotted type on the cam for the cam dowl. If you are going to use cam offset bushings, you will need the type with a hole drilled for the dowl. It needs to be drilled to accept the bushing.

If you have the engine out at this stage, pull the head. Put an indicator on the deck and absolutely identify TDC. I wouldn't worry too much about the cam break-in, just so long as the engine didn't spend much time at idle speed during the procedure. That's the killer.

CJ

Figured...

You might line up the dots as others have said and put the degree wheel on and see where things line up...if the numbers look good, you can button it up and take a ride (it should feel MUCH better at that point)...

If you maintained 2000 rpm for the 20 minutes etc...the cam and lifters should be OK.

If adjustments need to be made (i.e. off set bushings)...you can note the distance from the center of the gear to the cam dowel, then remove the gear and scribe a line through the slot and the center of the gear, then drill a new hole on the opposite side of the gear in line with the slot...the dots will be irrelevant at that point but you can now redegree the cam and bush it to match.

Quote:

Of course there are different interpretations and instructions given with different sets. Was the instruction on this set to point the dots AT each other?

It's an SA stock replacement gear set so the dots should point at each other like the stock sets, if installing the set on a "stock" engine...these don't come with instructions in them just the gears and the chain with the expectation that the dots get lined up and you're done...

-D.Idiot

Quote:

Of course there are different interpretations and instructions given with different sets. Was the instruction on this set to point the dots AT each other?

11 inches of mercury. ("HG) Have you checked it with an independent, known good gauge?

Don't give up hope. There are several factors that can play into poor manifold vacuum.

The basic is that the cam is what you think it is. If it isn't, then there's no telling what idle vacuum should be. Do you know what you have in there?

I had a cam in the Hooptie for a while that I was ecstatic to have 7 inches of mercury vacuum at idle. Not the cam you want in a driver. 1320 feet at a time, it was great fun.

I forget, do you have a hydraulic or mechanical setup? Did you get any documentation with your rebuild? The PN of the cam would be most helpful. Call your builder and get it. He should still have the info if he runs a brick and mortar outfit. Shade-tree, no telling.

Many of the aftermarket mechanical cams can't be lashed at OEM specs. Most of my OCG cams require lash settings of .025 to .028"
The one I just bought is .028"/.028". Sometimes it takes some experimentation to find the happy spot, as I have found most cam companies call lash a bit too tight. I'll probably end up closer to 0.030" or even more.

If modifications have been made to a hydraulic setup, the pushrods need to be checked to make sure they ride correctly in the lifter. If the lifter can't pump correctly, you could have vacuum issues.

Your not running hydraulic lifters with a mechanical rocker setup or vice-versa, right? Don't mean to be rude, just checking. It happens frequently, and will not work.

You say you can remove the lifters without removing the head. So you have a drool tube head? Can't think of any peanut plug heads I've seen that you could remove the lifters through the pushrod holes.

Keep hammering away at it. You'll get there!

Drill out the cam locating hole on the cam gear

Quote:

Drill out the cam locating hole on the cam gear

If you look at the pics his gear is the "late" aftermarket stock gear that has a machined "slot" in it instead of a drilled hole to locate the cam dowel...the only way to install the bushing is drill a new hole elsewhere on the gear and start from scratch, ignoring the dots on the gears...

Other than that, everything else will work.

FYI,

-D.Idiot

Author:	mattelderca [ Sat Feb 01, 2014 11:56 am ]
Post subject:
Quote: I guess maybe I am jumping the gun than but this is how the timing marks should appear according to my FSM And if you make one more revolution of the crank, they will line up that way! Nothing wrong there. Edit: Some stock timing sets don't time on TDC compression. As long as the dots line up your good, that might be tdc on intake stroke and not compression stroke. if you get my point.

Author:	1930 [ Sat Feb 01, 2014 12:11 pm ]
Post subject:
Quote: Quote: I guess maybe I am jumping the gun than but this is how the timing marks should appear according to my FSM And if you make one more revolution of the crank, they will line up that way! Nothing wrong there. Edit: Some stock timing sets don't time on TDC compression. As long as the dots line up your good, that might be tdc on intake stroke and not compression stroke. if you get my point. I had assumed that the dots needed to be lined up at the bottom closest to each other on # 1 compression stroke and assumed that was a universal set-up that the FSM would have indicated as well. I guess thats what I get for guessing. Shame on me for being so quick to point the finger, frustrated. Back to no idea now why the vacuum readings are so low. Will have to play around with degreeing a cam I guess, maybe that would improve the readings.... 11 pounds at idle. Thanks

Author:	ceej [ Sat Feb 01, 2014 4:39 pm ]
Post subject:
11 inches of mercury. ("HG) Have you checked it with an independent, known good gauge? Don't give up hope. There are several factors that can play into poor manifold vacuum. The basic is that the cam is what you think it is. If it isn't, then there's no telling what idle vacuum should be. Do you know what you have in there? I had a cam in the Hooptie for a while that I was ecstatic to have 7 inches of mercury vacuum at idle. Not the cam you want in a driver. 1320 feet at a time, it was great fun. I forget, do you have a hydraulic or mechanical setup? Did you get any documentation with your rebuild? The PN of the cam would be most helpful. Call your builder and get it. He should still have the info if he runs a brick and mortar outfit. Shade-tree, no telling. Many of the aftermarket mechanical cams can't be lashed at OEM specs. Most of my OCG cams require lash settings of .025 to .028" The one I just bought is .028"/.028". Sometimes it takes some experimentation to find the happy spot, as I have found most cam companies call lash a bit too tight. I'll probably end up closer to 0.030" or even more. If modifications have been made to a hydraulic setup, the pushrods need to be checked to make sure they ride correctly in the lifter. If the lifter can't pump correctly, you could have vacuum issues. Your not running hydraulic lifters with a mechanical rocker setup or vice-versa, right? Don't mean to be rude, just checking. It happens frequently, and will not work. You say you can remove the lifters without removing the head. So you have a drool tube head? Can't think of any peanut plug heads I've seen that you could remove the lifters through the pushrod holes. Keep hammering away at it. You'll get there! CJ

Author:	1930 [ Sun Feb 02, 2014 3:55 am ]
Post subject:
Quote: It's difficult to see what is wrong. Perhaps parallax based on the angle of the camera is hiding it from me. (Your date stamps are September of 2007 by the way.) Are the dots lined up through the centerline of the crankshaft and cam? If so, then the timing set is lined up correctly. The next step is to degree the cam. If it was one of the OEM replacement cams, it is most likely to have events that coincide with the MP244. That is the most common for a mechanical replacement over the counter. To degree the cam may require a different timing set. The one you have is the slotted type on the cam for the cam dowl. If you are going to use cam offset bushings, you will need the type with a hole drilled for the dowl. It needs to be drilled to accept the bushing. If you have the engine out at this stage, pull the head. Put an indicator on the deck and absolutely identify TDC. I wouldn't worry too much about the cam break-in, just so long as the engine didn't spend much time at idle speed during the procedure. That's the killer. CJ Quote.........Are the dots lined up through the centerline of the crankshaft and cam?............ I plan to verify this today Quote............To degree the cam may require a different timing set. The one you have is the slotted type on the cam for the cam dowl. If you are going to use cam offset bushings, you will need the type with a hole drilled for the dowl. It needs to be drilled to accept the bushing.............. I have no idea what you mean exactly here, I have looked at the degreeing cam deal in the engine faq section and see nothing about bushings, can you elaborate please, with pictures if possible. BTW Ken spoke highly of you Quote.........If you have the engine out at this stage, pull the head............. I do not have the engine out at this point but pulling the head really isnt that big a deal and I might just be doing that anyway to have some other head work done. On an un-related topic I have read somewhere on this forum about machine work being done on slant heads and the valves becoming sunk down too far into the head, do you know anything about this....I would like to read more about this if possible, Id like to verify all the work I had done was done correctly. Thanks

Author:	1930 [ Sun Feb 02, 2014 4:05 am ]
Post subject:	Re: Yep...
Quote: Figured... You might line up the dots as others have said and put the degree wheel on and see where things line up...if the numbers look good, you can button it up and take a ride (it should feel MUCH better at that point)... If you maintained 2000 rpm for the 20 minutes etc...the cam and lifters should be OK. If adjustments need to be made (i.e. off set bushings)...you can note the distance from the center of the gear to the cam dowel, then remove the gear and scribe a line through the slot and the center of the gear, then drill a new hole on the opposite side of the gear in line with the slot...the dots will be irrelevant at that point but you can now redegree the cam and bush it to match. Quote: Of course there are different interpretations and instructions given with different sets. Was the instruction on this set to point the dots AT each other? It's an SA stock replacement gear set so the dots should point at each other like the stock sets, if installing the set on a "stock" engine...these don't come with instructions in them just the gears and the chain with the expectation that the dots get lined up and you're done... -D.Idiot Quote............You might line up the dots as others have said and put the degree wheel on and see where things line up...if the numbers look good...............I will line things back up this A.M and make sure its not off a tooth or so. What numbers, I have a degree wheel, I found two of them stored away, Not sure which to use, you can see one has a notch that looks like it fits over the keyway on my crank, havent tried it yet. Dont I need the original cam specs in order to use these? I do not have these specs and wont have access to them, is the cam maybe marked somewhere, maybe a number that I could see if I were to remove it? Quote...........If adjustments need to be made (i.e. off set bushings)...you can note the distance from the center of the gear to the cam dowel, then remove the gear and scribe a line through the slot and the center of the gear, then drill a new hole on the opposite side of the gear in line with the slot...the dots will be irrelevant at that point but you can now redegree the cam and bush it to match............ Im afraid at this point I am not clear on any of this, will keep working on figuring it out though, eventually things will click and fall into place. Thanks

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Author:	1930 [ Sun Feb 02, 2014 4:07 am ]
Post subject:	Re: Yep...
Quote: Figured... You might line up the dots as others have said and put the degree wheel on and see where things line up...if the numbers look good, you can button it up and take a ride (it should feel MUCH better at that point)... If you maintained 2000 rpm for the 20 minutes etc...the cam and lifters should be OK. If adjustments need to be made (i.e. off set bushings)...you can note the distance from the center of the gear to the cam dowel, then remove the gear and scribe a line through the slot and the center of the gear, then drill a new hole on the opposite side of the gear in line with the slot...the dots will be irrelevant at that point but you can now redegree the cam and bush it to match. Quote: Of course there are different interpretations and instructions given with different sets. Was the instruction on this set to point the dots AT each other? It's an SA stock replacement gear set so the dots should point at each other like the stock sets, if installing the set on a "stock" engine...these don't come with instructions in them just the gears and the chain with the expectation that the dots get lined up and you're done... -D.Idiot Quote..........It's an SA stock replacement gear set ...............Thanks for this bit of info, I did not know that the SA stamped into them meant stock replacement.

Author:	1930 [ Sun Feb 02, 2014 4:14 am ]
Post subject:
Quote: 11 inches of mercury. ("HG) Have you checked it with an independent, known good gauge? Don't give up hope. There are several factors that can play into poor manifold vacuum. The basic is that the cam is what you think it is. If it isn't, then there's no telling what idle vacuum should be. Do you know what you have in there? I had a cam in the Hooptie for a while that I was ecstatic to have 7 inches of mercury vacuum at idle. Not the cam you want in a driver. 1320 feet at a time, it was great fun. I forget, do you have a hydraulic or mechanical setup? Did you get any documentation with your rebuild? The PN of the cam would be most helpful. Call your builder and get it. He should still have the info if he runs a brick and mortar outfit. Shade-tree, no telling. Many of the aftermarket mechanical cams can't be lashed at OEM specs. Most of my OCG cams require lash settings of .025 to .028" The one I just bought is .028"/.028". Sometimes it takes some experimentation to find the happy spot, as I have found most cam companies call lash a bit too tight. I'll probably end up closer to 0.030" or even more. If modifications have been made to a hydraulic setup, the pushrods need to be checked to make sure they ride correctly in the lifter. If the lifter can't pump correctly, you could have vacuum issues. Your not running hydraulic lifters with a mechanical rocker setup or vice-versa, right? Don't mean to be rude, just checking. It happens frequently, and will not work. You say you can remove the lifters without removing the head. So you have a drool tube head? Can't think of any peanut plug heads I've seen that you could remove the lifters through the pushrod holes. Keep hammering away at it. You'll get there! CJ Quote.........Have you checked it with an independent, known good gauge? ............... I have checked it with two different gauges Quote............Do you know what you have in there?............No idea whatsoever, I am assuming a generic stock replacement. Engine was just re-built. Quote............ I had a cam in the Hooptie for a while that I was ecstatic to have 7 inches of mercury vacuum at idle. Not the cam you want in a driver. 1320 feet at a time, it was great fun................... I have no idea what a Hooptie is but I will assume its slang for a style of vehicle. Quote.............. I forget, do you have a hydraulic or mechanical setup? Did you get any documentation with your rebuild? The PN of the cam would be most helpful. ............... I have hydraulic, no information for the cam is avail. Is there a part number on the cam I could see if I were to remove it? No modifications away from the hydraulic set-up Quote.............You say you can remove the lifters without removing the head. So you have a drool tube head? Can't think of any peanut plug heads I've seen that you could remove the lifters through the pushrod holes..............My engine is 1986, evidently from what I have read ( and posted info on ) I can remove the lifters without removing the head, have not attempted that yet.

Author:	1930 [ Sun Feb 02, 2014 5:23 am ]
Post subject:
Ok I have re-checked, this is again with the engine at TDC. It would appear that the cam gear is off. Very difficult to hold a screwdriver down the plug hole and turn the crank at the same time and get that sweet spot but I did the best I could and then had my wife help me by turning the crank as I just held the screwdriver. I am going to assume that the only way to get this ABSOLUTE TDC is by removing the head and using my dial indicator, is that correct? Or is there another way? What do you guys think? I know the picture is crappy, I am trying to shoot it through some front end sheetmetal.

Author:	Reed [ Sun Feb 02, 2014 11:07 am ]
Post subject:
I think: (1) pull the cam gear and remove the chain. (2) reinstall the cam gear (3) rotate the cam and crank independently until the dots line up (in stock form the slant is a non-interference motor, meaning the valves will never hit the top of the piston). Temporarily removing the rocker arm shaft will make turning the cam much easier. (4) remove the cam gear while moving the cam as little as possible. Reinstalling the rocker arm shaft will help hold the cam in place while you loosen the cam gear retaining bolt. (5) reinstall the chain and the cam gear (6) verify the dots line up now (7) use a degree wheel to determine the centerline of the cam (8) Remove the cam gear. Drill out the cam locating hole on the cam gear and use cam advance bushings to put the cam where you want it, if necessary (9) put it back together and check your vacuum at idle

Author:	1930 [ Sun Feb 02, 2014 2:36 pm ]
Post subject:
Thank-you Reed. You are right on the money. There are a few other things I plan to check first but ultimately I will be using these directions I am sure

Author:	DusterIdiot [ Sun Feb 02, 2014 2:59 pm ]
Post subject:	Nope..
Quote: Drill out the cam locating hole on the cam gear If you look at the pics his gear is the "late" aftermarket stock gear that has a machined "slot" in it instead of a drilled hole to locate the cam dowel...the only way to install the bushing is drill a new hole elsewhere on the gear and start from scratch, ignoring the dots on the gears... Other than that, everything else will work. FYI, -D.Idiot

Author:	Reed [ Sun Feb 02, 2014 5:20 pm ]
Post subject:	Re: Nope..
Quote: Quote: Drill out the cam locating hole on the cam gear If you look at the pics his gear is the "late" aftermarket stock gear that has a machined "slot" in it instead of a drilled hole to locate the cam dowel...the only way to install the bushing is drill a new hole elsewhere on the gear and start from scratch, ignoring the dots on the gears... Other than that, everything else will work. FYI, -D.Idiot Whoops! Good catch DI. I didn't look that close.

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