If I have to pull the cover, i'm going back to chain! [Archive]

john8662

05-30-2006, 00:15

In troubleshooting this annoying ticking I get I got to thinking about that annoying POS gear set I've got installed in the engine.

I went back and looked at the images of it installed on the block during assembly, I can't tell whether it's right or wrong.

Got out another gear set that I had purchased for another engine and played with it aligning the VERY uninformative little f'in dots.

Yes.. I'm not happy.

Anyways, I figured there were at least two ways that the dots "look" close, but which way is the correct way.

I remember seeing BobND's image of drawing a line, so I did that, counted the teeth on the big gear (48) and the little gear (24) and drew my line right in the middle, but at the teeth count it ain't in the middle, kinda odd. Especially considering the dot is not matched with a preticular tooth.

Got me thinking...

Which IS CORRECT?!?!?

Here are my two shots of the ways that I could manipulate the gears to get them to sorta line up. There is NO absolute center alignment of the marks whatsoever (that's what makes me furious).

Setup A:

http://members.cox.net/trialanderror/gears/First.jpg

Setup B:

http://members.cox.net/trialanderror/gears/Second.jpg

Here is the "image" from DSG's Paperwork... Notice the position of the key on both the cam gear and the crankshaft gear, then form your opinion on the gear position.

http://members.cox.net/trialanderror/gears/DSG_Desctructions.jpg

Finally, this is the same gear meshing as Setup A, but turned a little, notice how the dot is more towards the right hand side of the image. This is EXACTLY how it's installed in my engine currently.

http://members.cox.net/trialanderror/gears/FirstAppear.jpg

It's been a busy weekend on comparing these gear sets. I'm not impressed with the quality control between sets. I've got three of these things, and I compared them and they vary on the position of the dots on the gears, hmm..

BobND

05-30-2006, 05:49

I made a mark on the gears opposite the timing marks, by counting the spaces and teeth to locate a mark 180 degrees from the factory mark, and then drew lines on the gears. Made it more clear how they should line up, I THINK.

http://ndtc3500.stellarnet.com/~blweltin/Bob/DSGtimingMARKS.jpg

After all that, I used a chain set, because I found nasty main web cranks, and figure the engine will only go some thousands of miles before the lower end grenades.

I set the IP timing to the factory line, and it sounds GREAT, although I have not taken the time to check it with the MT-1480.

If I mess with these gears again, I'll degree the cam, first with the chain set, and then with the gears.

It's too much trouble, and too much MESS to take a chance on having to do it twice!

john8662

05-30-2006, 06:42

Bob,

Do you have another version of that image, or still have the gearset sitting around?

I want to see an image similar to the angle posted above that I took, straight down.

From the looks of it, your image matches Setup A.

Right now I'm troubleshooing IP issue or internal timing issue caused by this gearset. Don't want to swap the IP to find out that wasn't the cause, and vice versa.

New chainset by Cloyes is right at 69.00, looking tempting.

More Power

05-30-2006, 08:26

Set the damper timing mark to exactly 0 degrees before pulling it and the front cover. You'll find the timing dot on the crank sprocket (or gear) will be at exactly 12:00.

Set a straightedge on top of the crankshaft and align it to exactly center over the cam bolt hole. Now align the dot on the cam sprocket (or gear) to exactly align with the straightedge (at either 12 or 6:00 - doesn't matter).

There is no way that I can see how you can wind up with a tooth off, one side or the other. A tooth off will be very obvious.

I've personally installed 3 gear drives as well as a few chain sets. It's not rocket science.... :)

Jim

john8662

05-30-2006, 08:43

There is no way that I can see how you can wind up with a tooth off, one side or the other. A tooth off will be very obvious.

I've personally installed 3 gear drives as well as a few chain sets. It's not rocket science.... :)

Jim

What cha mean by very obvious? Some symptoms would be helpfull.

I think I better take up rocket science, because this preticular 6.2 is harder to figure out...

More Power

05-30-2006, 09:55

Here's the last gear set I installed. A straightedge sitting on top of the crankshaft at 12:00, and aligned with the center of the camshaft bolt hole showed the dots on both the crankshaft and camshaft gear to be in exact alignment.

http://www.thedieselpageforums.com/photopost/data/500/gearsettimingdots.jpg

Each camshaft gear tooth is quite wide, which would be pretty easy to see if it was installed one tooth off. :)

Jim

Warren96

05-30-2006, 10:03

You are absolutely right those marks on the gears are not at all like the instructions show you how they should be aligned.And in retrospect of when I did my gears,I was also confused as of wich way to go as my gears were marked just like yours! But to get back to your ticking; can you take off the oil fill cap and hear the sound get louder?

DmaxMaverick

05-30-2006, 10:46

Also....

If the cam gear is one tooth off, it will show one tooth off. If the crank gear is one tooth off, the cam gear will show 1/2 tooth off. In any case, the teeth are large enough you can't be a tooth off on either, and not see it. They're either on, or not. Unfortunately, we have to depend on the timing marks being correct. I've had sprockets mis-marked, and a week of headaches to follow. Finally degreed the cam, and could have shot the mfg! I also use the straight edge method to set timing marks. The gear teeth are seldom alligned with the marks, due to cam timing specs.

john8662

05-30-2006, 12:11

Thanks for the suggestions and reasons.

I do see that it's possible if the crank gear is one tooth off that you could get 1/2 off on the cam 2:1 ratio.

This engine doesn't like these gear sets. I think I've got too much clearance and cannot convince DSG of this (have spoken to them about it and what to check).

For one, the amount of space that you're supposed to have between the idler axles and the front timing cover is very large on my engine, where as it's shown to be a lot less on others (even requiring shaving).

I've got the chain set on order and this weekend I'll tear it all down (really not wanting to do this project) and see where the alignment is. This is the 2nd gear set this engine has had, same results in the end.

I really like the dot at the top method MP!

inally degreed the cam, and could have shot the mfg! I also use the straight edge method to set timing marks. The gear teeth are seldom alligned with the marks, due to cam timing specs.

Hmm, that explains why the dot's don't align with the teeth, afterall the keyway is placed on the gear at some point too. A Degree wheel is on the want list for tools currently, but have to purchase some other engine building tools for the race engine...

J

DmaxMaverick

05-30-2006, 13:38

You don't need to buy a degree wheel. I never have. Make one (as with most of my "specialty" tools). Very easy. I have to make one just about every time I need one. I like to use a Tupperware lid (or similar). Mark the outer circumference of the lid with a fine point sharpie, at 36 equal points (10

gmctd

06-02-2006, 10:54

Problem is - the cam gear tooth cannot line up with the crank gear valley because of the pitch of the idler gears.

When the marks are aligned, as JimB indicated, timing is correct.

The drawing is wrong, except for aligning the dots.

And, yes - I've launched a few rockets, in my time. :eek:

grape

06-02-2006, 16:04

1 tooth is almost 17 degrees of crank timing..........

gmctd

06-02-2006, 20:35

And, at +17deg or -17deg variance from correct timing, ain't much way you would not notice the difference in starting and running.

Also, guess I should have been more specific - the crank and cam teeth cannot line up when cyl#1 is at TDC, but the indicated timing marks will align cam and crank for correct timing at #1 TDC.

I've rather enjoyed watching the stability of Des\Act timing with the DSG gearset, as compared to the chainset, and not even to mention the added quietness of the gears over the chain and sprockets.

As I've mentioned before, even a new chainset sounds like a chainsaw chain chattering on an iron pipe, while listening thru the oil-fill tube with the cap off.

There is just a not-unpleasant mechanical whirring sound with the gears, and which absolutely cannot be heard above the injector tick when the cap is on.

Put yer timin' cover back on John - maybe you're just new-engine gun-shy fer a while...........

arveetek

06-03-2006, 07:21

There is just a not-unpleasant mechanical whirring sound with the gears, and which absolutely cannot be heard above the injector tick when the cap is on.

My gears make an awful racket at idle, murch more noise than the diesel rattle can cover. However, it's due to the fact that my engine has a nasty lope at idle, which causes the gears to load up and release, load up and release, over and over.....I'd describe the noise at idle as "ching ching ching ching ching...." in time with the engine pulses.

If I could figure out why the engine runs that way, I'd cure my gear noise. The lope goes away at higher rpm, and the engine runs like a scalded ape just as smooth as can be at higher rpm.

Casey

gmctd

06-03-2006, 08:55

arveetek

06-03-2006, 09:21

Yep - that would generate some floating idler gear noise, particularly with square-cut gears.

That same noise can be heard while back-and-forth'ing the crank by hand.

Wonder if the IP housing pressure is varying, causing the advance to vary?

- what lift pump are you using?

-have you checked the fuel return line for plugged, starting at the outlet on the IP, thence back to the tank?

I'm using an electric lift pump pushing about 5 psi. I haven't checked the fuel return for restrictions, but now that you mention it, I suspect I have a problem there. The engine surges quite bad when the HPCA is engaged, and it's started surging lately when you let off the accelerator, such as when slowing down and allowing the engine compression to hold you back when coming down a hill.

Could a restricted return line cause idle problems? Could I remove the fuel line and run a temporary line into the tank to see if the idle clears up?

Another symptom to my idle problem is that it idles fine when cold, but after warming up to normal temperature, it starts this loping. Engaging the HPCA manually on a warm engine does not clear it up either.

Sorry to hijack your thread, John!

Casey

gmctd

06-03-2006, 09:25

If you're still a moderator, here, Casey, feel free to cut and splice this into a new thread..................

arveetek

06-03-2006, 10:05

If you're still a moderator, here, Casey, feel free to cut and splice this into a new thread..................

I'm a moderator on the towing forum only. John, you could do the cutting and splicing if you'd like!

Casey

john8662

06-03-2006, 18:55

I'm leaving the posts the way they are, actually they kinda add to the general problems that can be associated with a Gear Set that go un-noticed with the chain (noise wise).

Interesting note about the injection pump loading the gears. I've often wondered if the IP on the truck could be culprit. All my fuel lines are in good shape, no surging, just powerstroke rattle when HPCA is engaged (ain't kidding either).

Feel free to start a new thread in the 6.2 forum if you deem it necessary, also search for surging and see what comes up...

Well, back on task. Had to work all day Saturday to make some $$ to pay to pickup the chain set, front cover gasket set and gear puller from the auto parts store. The inspection of the gear timing alignment will commense on Sunday, followed by a replacement timing chain.

Will report back!

J

john8662

06-04-2006, 17:43

Well, the cover is off and I checked things according to the excellent suggestions so far. I used the straight edge with the cam gear timing mark pointed up and everything lined up just like pictured. So the physical timing of the gearset installed on the engine is correct. I also had put the mark on the balancer to "0" on the timing tab and the dot was directly up as expected on the cam gear.

I'm in the process of installing the timing chain set I got, I see no other reason to leave the gears in at this point. I also need a comparison between tight fresh chain and gears. Always gone from pretty sloppy chain to gears.

I will know more about the noises later this week. Things are going together well and should be completly back together tonight (Sunday) but will wait to fill with fluids after things have a chance to dry.

gmctd

06-04-2006, 18:25

Well, it's a cryin' shame, but ya gotta do whatcha gotta do.............

Oddly enough - I went from a new chainset to the gearset while troubleshootin' a strange tickin' noise.

I'll not jinx ya by sayin' what it was, bit it warn't the timin' train..............

'Course, I gotta DS4 and you gotta DB2........

john8662

06-05-2006, 16:53

Well, the engine has been restored to life with filling the dry cooling system back up with prestone.

Upon first start I noticed an immediate difference between the two sets. The engine is MUCH queter, this in in the form of the diesel rattle, usually caused by TOO much advance. Bye bye powerstroke!

I can hear the chain sound, but it's much queter than the gears were, I can actually hear that noisy DB2 ticking as usual.

The other ticking noise is gone or much quieter, I can't tell. I'll know more with more driving.

I do think there is a built in advance to the gears, not just the speculated phaser gear used on the electronic 6.5's.

gmctd

06-05-2006, 18:02

Good job.

2 much advance for the mech DB2 - what was idle speed, previously?

john8662

06-05-2006, 19:48

The idle speed as reported by the ISSPRO tach in the cab is ~630-650 RPM hot idle.

Haven't looked at it yet after the gear swap, although I can't say that it would have moved. I didn't change anything with the pump. just it's alignment according to the mark on the cover. But, it does sound like it's lower, definitly less advance for sure.

Before, with the gears, moving the pump one side to the other didn't change the engine sound much if at all. Now, I bet it will be more responsive, if I want more advance. It's line to line, but I ain't got no timing meter (thanks bid snipers on ebay).

J

gmctd

06-05-2006, 20:46

I don't recall anyone but Britannic that has\had one - anybody heard from him, since he went NAPA?

Aymr, he would up being quite an authority on DB2 IP timing.

Your 'powerstroke' description sure sounds like an EFI DS4 with too much TDCO, which is calculated based on mechanically advanced position.

The extra noise may have been due to the DB2 two-plunger rotor having coarser pumping action, reflecting back into the gearset, tho I don't recall JimB having any similar problem with the Project Truck.

Or coulda been the increased dimension you mentioned, between the timing cover and the idler-gear shaft - mine is right on spec, JimB had to 'machine' his for clearance.

TBOGEMIREP's '98 EFI truck makes some hellacious low-idle noises with the hi-pop\hi-flow injectors, sounds like the crank is coming out of it, and he has the oem chainset.

As you mentioned, this is a good gearset vs chainset noise thread.

john8662

06-05-2006, 22:38

Another oddity not mentioned nor pictured is the marks where the idler axles had hit on the inside of the timing cover. There were two half-moon indention/wear marks starting. It's almost like the idler gears were bouncing back and forth, hence the noise.

I'm keeping the gear set just in case, building a 6.5 in the next couple of weeks using 6.2 externals (including timing cover), I'll setup this gearset in it and see what happens...

Northern Wrangler 6.2

06-09-2006, 05:12

Hey fellas....just thought I'd add, I know it's an old thread...but...

In the fall of 2004 I added the DSG gear set to my truck, 150,000 miles, chain was whipped....the install was a fair job, will be easier on the next truck I'm sure. I noticed a difference in running, better starting (timing) and better power. No real noticable noise. I have installed a manual fast idle switch though, and rarely leave the truck at low idle when stopped. I found an MT1480 on EBay fall of 2005, and it works slick. I was off by several degrees with my "by ear" attempt. EGT's were high under load, steep grades, etc. Now that I've been able to set the timing, I am very happy with my gear set purchase. Is it worth 4x the price of a fresh chain and gears, not likely, but it won't stretch......lol I think I need to turn my pump screw back a bit, I opened it up before the gear install and I think I'm spewing dead dinosaurs for nothing....too much black smoke under hard acceleration....turns my rear quarter panel black when towing.

In conclusion.....my engine is very quiet at idle when warm....hard to tell much difference from before, In fact, it might be less noisy....I hear lots of intake roar and exhaust (Banks Stinger).....but that's it.

GOOD TRUCKIN' !!!

Warren96

06-09-2006, 09:45

john8662

06-09-2006, 23:41

Well, been driving the pickup all week a couple of major changes...

First, I used to have a light white smoke at idle sitting at a light at night (annoying) and a general haze under light acceleration, hot outside.

Now, no smoke at idle in the headlight behind, and it doesn't smoke all the time now, much better.

The fuel economy seems to have IMPROVED since the swap, the timing was TOO advanced before, and it looked good on the meter, but I couldn't get it off the advance by rotating the pump in reasonable amounts towards the passenger's side.

I just don't know...

It's running better, not starting better though, that's the only side-effect now.

Before, bump the key, it was running, cold, hot didn't matter. Now, starts great cold and with plugs, but hot with no plugs leads to me cranking on it for a bit, then coming to life with white smoke for less than one second then running normally.

I have have had a pump problem all along, because the symptoms I'm seeing at this point say "bad head and rotor" in the IP...

But, why the heck did it start so great with the gears and the immense amount of advance?

Another possibility, maybe my IP driven gear is stamped one tooth off or something? And, it's close enough with chain, etc. but not with the ~2 degree advance with the gears?

So, GMCTD, what's yer theory on the ticking thing? I have a feeling you're gonna say it was your DS4, I'm thinking it's my DB2, this may actually fuel the DB2 to DS4 conversion now... The ticking is almost non-existant, but still there only when kinda cold, then gone the rest of the day, only on hard accelerations too...

I like my chain thank-you-very-much!

J

More Power

06-10-2006, 13:11

DSG performed a number of engine/chassis dyno comparisons when they first introduced their gear drive. They documented a 5-7 hp improvement a number of times.

Member Greg Mead, who runs a fuel injection shop in North Idaho ran a mechanical 6.5 on an engine dyno, and compared a chain timing set to DSG's gear drive. He documented a similar hp improvement.

Member Scott Boelman in Billings, MT worked with me in 1998 to install a DSG Phaser gear drive in his 1994 6.5TD K2500, then compare the performance & fuel economy changes to when his engine was equipped with the original chain set (still in spec). He too, saw a performance improvement (40-70 mph roll-on time in 5th gear - NV4500), his fuel economy got a bump and it cured an annoying drivetrain vibration he had worked to resolve for some time prior. That article appeared online here in TDP at that time.

The 6.5 fuel economy engine I'll be assembling later this summer will get a DSG gear drive.... :)

Jim

britannic

06-10-2006, 22:32

Still alive, but furiously overworked as we rebuild our NAPA store from the ground up! GMCTD, what is your question - about the timing meter, gears or ISSPRO tach? Later, Britannic...

I don't recall anyone but Britannic that has\had one - anybody heard from him, since he went NAPA?

Aymr, he would up being quite an authority on DB2 IP timing.

john8662

06-10-2006, 22:56

Not saying the gear drive is bad.

I think the increase in HP is solely due to the advance, which is noticeable.

There is a nice balance on timing for how the engine will perform, too much of any one or the other and things just don't run right, that's what I'm into.

For some reason this preticular (and Casey's) engine has an issue with it.

Could be the align bore of the engine from factory, could be cover clearance is really too excessive, could be my IP driven gear, I dunno.

Nothing is ever easy.

I have a feeling I'll be R&R'ing the IP this next week for an evening to install a 4911 pump in place of the 6.2 milspec new pump. I should know more then about the new odd hot start issue...

It's still possible the gearset could return to the engine...

mhagie

06-11-2006, 07:18

mhagie

06-11-2006, 07:24

I have been reading this thread with a lot of interest because i just installed a gear drive last fall.Mine has the stock exhaust so it is very easy to hear a different noise from the engine.After it was installed the timing was set to the chain timing marks and you could tell by it's sound that the timing was too far advanced. There is a big difference in timing between a stock chain and a gearset! Like More Power said you do have to retard a gear about 3 to 5 degrees (1/16th to 3/32nds) from a chain.MPG is up over 4, and the oil stays much cleaner! The only time you can hear a sound from my gear is to take the oil fill cap off and lean over the engine!

Where did MP say you retard timing with a gear set?
Knowing me I looked right at it and it still went right over the top of my head.
maybe I should retard mine sme more?
Mine was the width of the line to drivers side and was as mentioned 5* ATDC @1400 it it still hammers very loud, mine could drown out a powerstroke and give a Cummins a good run for its money.
Merle

gmctd

06-11-2006, 08:44

Hi Britannic -

Glad to hear you're busy - hope that means 'prosperous'.

In light of John's problems, was just mentioning that you had obtained a mech inj Diesel timing meter, and that I could not recall another, here.

Other than the excessive noise, which I think is due the idler shaft clearances and possiby low idle and the harsher DB2 pumping pulses, there is also some question as to timing differences between the chainset and the gearset, as arveetech and John are experiencing some difficulty with the gearset.

Most notably, the DP Project Truck with marine DB2 had no problems, nor has my DS4, and many others, given no problems.

Defective gears? Unkown timing? Gremlins?

?Quien sabe.

Warren96

06-11-2006, 17:12

More Power responded to Max Egli about''Dynamic Timing Question'' on 11-16-2005 and mentioned retarding the timing. By the way, isn't turning the pump to the drivers side advancing the timing?

britannic

06-12-2006, 06:48

You're correct, turning toward driver's side=advance.

More Power responded to Max Egli about''Dynamic Timing Question'' on 11-16-2005 and mentioned retarding the timing. By the way, isn't turning the pump to the drivers side advancing the timing?

More Power

06-12-2006, 11:08

Just to add to the above... Yes, I needed to retard fuel injection timing after installing a gear drive (move the top of the pump to the passenger side). For example, when the 6.5 Project engine went together (with a gear drive), I lined up the timing index marks on the pump flange and the front cover for its first start. It rattled scary loud when first started. I eventually retarded injection timing about 3/32" at the timing marks (IIRC). Still rattled pretty well, especially when cold, but rattle was difficult to discern while on the highway at 65-mph or while under boost.

The last DSG gear drive I installed was in a 1996 electronic engine. Timing was adjusted using a Tech II once the engine was running again. I don't remember Todd Day (his "Phoenix" rebuild in 2002) mentioning a need to do anything special when he had the timing checked.

DSG mentioned in their early literature (may still do) that timing is advanced (both injection & cam). This may account for some of the power advantage offered by their gear drive, when compared to a new timing chain set.

Jim

gmctd

06-13-2006, 10:32

Was the timing cover marked from the factory or at a later date, and with which IP?

Same for the Inj Pump mark?

My xeroxed sheet indicated nothing about timing, except for the cartoon indicating a vertical line thru the marks on the gears.

78Chev

06-15-2006, 12:54

DSG mentioned in their early literature (may still do) that timing is advanced (both injection & cam). This may account for some of the power advantage offered by their gear drive, when compared to a new timing chain set.
Jim

Can someone explain how advancing the cam a couple of degrees results in more power? Why would you would do this with gears and not a chain? Thanks for helping my feeble mind learn something new!
Randy

More Power

06-15-2006, 16:01

Can someone explain how advancing the cam a couple of degrees results in more power? Why would you would do this with gears and not a chain? Thanks for helping my feeble mind learn something new!

Don't know.... Other than I've seen the dyno & performance data.

By the way, once broken in, the 6.5 project engine was the smoothest running 6.2/6.5 I've been around - then or since, and was as smooth running as any Duramax I've been around. Certainly, the precision balanced rotating assy partially explains why, as would a fresh fuel injection system. I also partially attribute the smoothness to the gear drive.

Jim

john8662

06-15-2006, 20:39

As for smooth.. I feel one major thing played a role there, reduced compression ratio!

arveetek

06-16-2006, 14:03

As for smooth.. I feel one major thing played a role there, reduced compression ratio!

I'm not sure about that....my reduced compression ratio engine doesn't idle very smooth. Of course, I'm not reduced down to 18:1 either.

My stock 6.5L DS4 engine idles and runs much, much smoother than my custom 6.2L DB2.

I'm still convinced that I have something that's not quite right causing a stumble at idle. It might be a problem in the fuel injection pump or in the valve train. I did pull the return line off the injection pump and ran another line into bucket bypassing the fuel return to the tank, but it didn't make any difference, so I'm sure it's not related to the fuel return system. I had a pretty good fuel flow out of the return line off the injection pump, too.

The engine has gotten to where it's surging when decelerating as well. If I let off the throttle and the TC's locked up, I can really feel it. Don't notice it at slower speeds or when the TC's unlocked. I'm starting to think my IP might have problems.

I'm convinced that once I get the engine stumble resolved, that the DSG gear noise will go away and that I'll have a silky smooth engine.

Casey