Help a NOOB - A continuing saga

[Artofdeath]

Not every day I say this to another guy but nice looking rear end you got there!

[ncpetersc]

:LOL:

Thanks for the all the info guys, I will try to put it to use.

I always feel confident after reading about this stuff, but it fades when I try to put it to use. I guess these things aren't an exact science, so if I try to follow advice and things start to not seem right, I don't have the experience to know what way to go. Like dmjlambert knowing what he heard, and that he needed to retard timing to fix it. Basically I lack experience; Give me a number and I can set it to that, if that number isn't exactly right for my scenario I get lost.

[geezer#99]

Originally Posted by dmjlambert

The detonation (or ping or knock) on my truck sounded very much like a rattle from under the hood. I could hear it while accelerating on a test drive. So I retarded by timing by a couple of degrees and took it for a test drive again. I repeated retarding the timing until the pinging was gone. I ended up at 7 BTDC and my vacuum advance gives 23 degrees of advance. I had a separate thread here on the forum about those numbers and using the timing light.

Just imagine how it would run with 14 initial and 15 from vacuum. Way more power and likely better mpg’s too.
You can easily limit the vac advance with a limiter shown in here. You could even make your own.
http://www.crankshaftcoalition.com/w...EI_distributor

Sorry for the sorta highjack!
That link might help the op in the long run!

[ncpetersc]

Finally "uncovered" the fill plug. Oil began oozing out as I unscrewed it. I just tightened it back up. I think the rear end is good.

Noticed the bearing support(?) to be sloppy. I could push it up and down maybe 1/16 to 1/8 inch. Could this be the whine I hear? Going to look into replacement procedure/parts for this next I think.

I think the piece in this picture is worn/collapsed.

Did not mess with timing again yet. The more I read the more confused I get, but I'll figure it out!

[ncpetersc]

Back again.. and as confused as ever. (You sick of me yet?)

So I decided to try to "tune" again. About all I did since installing the new (rebuilt) carb was lean (turn in) the idle about half a turn.

Today I decided to start with the distributor first. I warmed the engine up, then turned it to find where it ran well. I have been at 12deg pretty much since my ordeal began, based on advice here which helped immensely.

Anyway, I start advancing it further and the engine likes it, rpms up vac up a little too. I got all the way to 26deg when I stopped turning and checked it! This doesn't make sense based on what I have read. Vac was up to about 23-24inches. RPM had risen to about 850. Because it didn't seem right I thought the mechanical might have kicked in, nope. Then I noticed I forgot to disconnect distributor vac. Well I did and plugged it, still nope.

My distributor vac I have never seen kick in, I think because it is either ported vac, or through the TCS solenoid or both.

Anyway, I backed it off a little, leaving it at 22deg advance, giving 20 inches vacuum, and adjusted idle to about 690 rpm.

I then leaned idle by another half a turn, and readjusted idle to about 690rpm, vacuum was still good.

I went another half and vac started bouncing 18-20, so I backed that out.

I am now probably one full turn in on the idle screws vs. when I got it from the remanufacturer.

It seems to be running well, and respond well to throttle.

Seems okay from readings, but what is with the severe advance (I think) of 22 degrees?

I am about to take it for a test drive, but would love to hear your thoughts.

Thanks!

[dmjlambert]

How many vacuum ports do you have on the carburetor? At idle, one of them should suck and hold a small piece of paper to the port. That would be the manifold vacuum port. Another port may be one that does not have any suction at idle, but above idle it will have suction. That is ported vacuum.

When you are at idle speed and you connect the distributor vacuum advance to manifold vacuum and disconnect it, and reconnect it again, you should notice a difference in idle speed. That is your vacuum advance working. If your vacuum advance does not work at all, then perhaps there is something wrong with it.

If vacuum advance is working OK, then I suggest:
Disconnect distributor vacuum and plug port on the carburetor with a rubber plug, and set the initial timing at 12 BTDC when idling at roughly 400 to 700 RPM. Then connect distributor vacuum to manifold vacuum, which should increase the idle speed. Rough adjust idle speed again 700 RPM, then chock tires, put parking brake on, and transmission in drive and adjust idle to 600. Stand to the side when adjusting the idle speed. Then take it for a test drive and listen for pinging. If it pings, reduce your initial timing by a couple degrees and repeat test drive.

[Steeveedee]

As old as the truck is, it is entirely possible that the harmonic balancer elastomeric ring has allowed the outer metal ring to slip. When this happens, you have an apparent advance in the timing mark on that ring. You will have to determine where TDC actually is, and compensate for that. The fact that you are running well at 22° "base" timing is a potential indication. If it isn't pinging at that setting, leave it for now. Were it mine, I'd be for verifying that the balancer is OK. Two reasons- next time you take it to a shop and they adjust the timing, you'll be back to square 1; secondly, if that ring is actually deteriorated, the outer steel ring can fall off. Bad to worse, I'd say. I'm not claiming that the balancer has slipped, I'm only pointing to a possibility.

I worked as a SMOG mechanic for many years, and we'd get vehicles rejected from the test-only stations because of "over-advanced" timing. We'd have to diagnose it correctly and send the customer back with information indicating that the balancer had slipped. I always recommended they get it fixed, and if they had a favorite mechanic (not all of them had a SMOG license), they could take it there. I'm not one of those guys who sold them the parts and labor before I signed the paperwork off.

[ncpetersc]

Originally Posted by dmjlambert

How many vacuum ports do you have on the carburetor? At idle, one of them should suck and hold a small piece of paper to the port. That would be the manifold vacuum port. Another port may be one that does not have any suction at idle, but above idle it will have suction. That is ported vacuum.

When you are at idle speed and you connect the distributor vacuum advance to manifold vacuum and disconnect it, and reconnect it again, you should notice a difference in idle speed. That is your vacuum advance working. If your vacuum advance does not work at all, then perhaps there is something wrong with it.

If vacuum advance is working OK, then I suggest:
Disconnect distributor vacuum and plug port on the carburetor with a rubber plug, and set the initial timing at 12 BTDC when idling at roughly 400 to 700 RPM. Then connect distributor vacuum to manifold vacuum, which should increase the idle speed. Rough adjust idle speed again 700 RPM, then chock tires, put parking brake on, and transmission in drive and adjust idle to 600. Stand to the side when adjusting the idle speed. Then take it for a test drive and listen for pinging. If it pings, reduce your initial timing by a couple degrees and repeat test drive.

The test drive seemed pretty good, didn't hear any knock. I do definitely need to check that the vac advance is working. I'll test by putting to what I know is a manifold port because that is where I have been connecting my gauge. I have been assuming its okay but the TCS solenoid is locking it out at idle.

Thanks!

[ncpetersc]

Originally Posted by Steeveedee

As old as the truck is, it is entirely possible that the harmonic balancer elastomeric ring has allowed the outer metal ring to slip. When this happens, you have an apparent advance in the timing mark on that ring. You will have to determine where TDC actually is, and compensate for that. The fact that you are running well at 22° "base" timing is a potential indication. If it isn't pinging at that setting, leave it for now. Were it mine, I'd be for verifying that the balancer is OK. Two reasons- next time you take it to a shop and they adjust the timing, you'll be back to square 1; secondly, if that ring is actually deteriorated, the outer steel ring can fall off. Bad to worse, I'd say. I'm not claiming that the balancer has slipped, I'm only pointing to a possibility.

I worked as a SMOG mechanic for many years, and we'd get vehicles rejected from the test-only stations because of "over-advanced" timing. We'd have to diagnose it correctly and send the customer back with information indicating that the balancer had slipped. I always recommended they get it fixed, and if they had a favorite mechanic (not all of them had a SMOG license), they could take it there. I'm not one of those guys who sold them the parts and labor before I signed the paperwork off.

Something is up for sure. The motor is only about 16 years old, but it still might have happened. I'll read up again about finding TDC, I don't want to have to take too much apart at this point, or buy some special tool to turn the motor by hand.

Thank you!

[Steeveedee]

Originally Posted by ncpetersc

The test drive seemed pretty good, didn't hear any knock. I do definitely need to check that the vac advance is working. I'll test by putting to what I know is a manifold port because that is where I have been connecting my gauge. I have been assuming its okay but the TCS solenoid is locking it out at idle.

Thanks!

Right. Just go to manifold vacuum to supply the advance canister. Though if you have a pump with a gauge on it, you can just pump up a vacuum, if you only have the vacuum advance connected.

[68 P.O.S.]

Why do you still have the TCS connected, and does it actually work still?? If it works, and correctly, it's not allowing the vac advance to come in just yet as designed. I would disconnect it and remove the wiring; it was an early, crude emissions thing and it provides no benefit to your engine and only stops your vac advance from working correctly. The only people who really still use the TCS are those doing a factory correct restore, or they just don't understand the TCS. Plug your vac advance can directly to manifold vac and you should see the idle increase. If not, you have a bad vac can. Now you need to find out how many degrees of advance your vac can provides. You want it to be around 10 degrees, or you'll probably get pinging if it has more than that.

[ncpetersc]

Originally Posted by 68 P.O.S.

Why do you still have the TCS connected, and does it actually work still?? If it works, and correctly, it's not allowing the vac advance to come in just yet as designed. I would disconnect it and remove the wiring; it was an early, crude emissions thing and it provides no benefit to your engine and only stops your vac advance from working correctly. The only people who really still use the TCS are those doing a factory correct restore, or they just don't understand the TCS. Plug your vac advance can directly to manifold vac and you should see the idle increase. If not, you have a bad vac can. Now you need to find out how many degrees of advance your vac can provides. You want it to be around 10 degrees, or you'll probably get pinging if it has more than that.

Okay, thanks again for the info. I have read abut the TCS, and thought I might remove eventually. But I have been trying to move forward while changing as little as possible. That being said, it seems like now would be the time to remove it so I can check the vac advance. I've got a drive shaft issue to deal with, but I will get back on this soon.

[68 P.O.S.]

Glad I could provide a little insight Yes, definitely a good time to remove it Let us know how it goes and good luck with the drive shaft

[Steeveedee]

The TCS system was used to limit vacuum advance until the vehicle was warmed up and in high gear. This served to cause faster warm up and to limit hydrocarbon emissions. It is pretty much only a California emissions system, and can be bypassed if you want. Simply take the vacuum to the thermostatic switch (if still so equipped) and connect it directly to the vacuum advance chamber. You can also remove all the wires, if you want, as they won't serve any more purpose once the vacuum side is dealt with. You might want to keep the parts in case someone wants to put their system back to stock.

[ncpetersc]

Looking for advice with the driveshaft. Thought I could remove straps on rear yoke and carrier mount then push forward, drop back of it then pull out entire thing from rear. I can’t push it forward enough to disengage trunion. Would jackingh up rear frame to extend suspension help? I don’t know that I can disassemble a different joint under there.

[Steeveedee]

Get a big screwdriver (playing "Primitive Pete music, here) and pry the u-joint out of the diff trunnion. You don't even want to try and pull a u-joint underneath the truck, believe me! Your front spline is probably just caked with dry dust-filled grease. You can raise the truck to help get the driveshaft out, but when you go to install the center support bearing onto the frame, you must have the wheels on the ground with the truck's weight on them (or jack stands under the axle) so that the center support is aligned properly fore-to-aft. Otherwise the bearing can pop out of the carrier. AMHIKT.

[ncpetersc]

Originally Posted by Steeveedee

Get a big screwdriver (playing "Primitive Pete music, here) and pry the u-joint out of the diff trunnion. You don't even want to try and pull a u-joint underneath the truck, believe me! Your front spline is probably just caked with dry dust-filled grease. You can raise the truck to help get the driveshaft out, but when you go to install the center support bearing onto the frame, you must have the wheels on the ground with the truck's weight on them (or jack stands under the axle) so that the center support is aligned properly fore-to-aft. Otherwise the bearing can pop out of the carrier. AMHIKT.

I gave up, put it back together, and called it another failure for me (before I read this). It was easy enough to get the straps off and carrier mount loose, maybe I'll try one more time before giving in and looking to get it done someplace. I didn't try any prying just "sliding" it forward like the manual says. But it really isn't moving. What part slides? Way up at the tranny correct? Maybe I will look up there and see if I can "clean" at all.

Thanks again!

[ncpetersc]

Originally Posted by Steeveedee

Get a big screwdriver (playing "Primitive Pete music, here) and pry the u-joint out of the diff trunnion. You don't even want to try and pull a u-joint underneath the truck, believe me! Your front spline is probably just caked with dry dust-filled grease. You can raise the truck to help get the driveshaft out, but when you go to install the center support bearing onto the frame, you must have the wheels on the ground with the truck's weight on them (or jack stands under the axle) so that the center support is aligned properly fore-to-aft. Otherwise the bearing can pop out of the carrier. AMHIKT.

You were right Steeveedee! Thanks! Very little prying popped each side loose, and voila! Now, of course, I am in real trouble! Think I am going to attempt this myself first! Gonna head to the auto parts store and see about getting a loaner u-joint tool kit, and maybe a puller to try to use on the bearing, and parts.

THANKS! Wish me luck, and if you can think of any helpful tips, fire away guys!

[Steeveedee]

Just be careful not to drop the needles in the bearing cups when you put the cross-shafts into them. If the cups stop before being all the way to where the snap rings are installed, pull it apart and check it.

[stsalvage]

Remember to mark the drive shafts ends the way you took it apart.If you clock it wrong it will vibrate like a mother

[ncpetersc]

Been paying attentiin and marking. I’m stuck on the carrier bearing it won’t budge. Got a puller but can only grab outer race. Dust shield in the way for any try at inner race. Puller is really torqued but it usn’t Moving. Any thoughts or ideas?
Thank you again. Leaving puller on and soaked with blaster. Hoping for some miracle luck. I am wiped...

[Steeveedee]

Try leaving the tension on it overnight and the blasting agent will likely loosen it up. Do you have a propane torch? If you have the support off the bearing, you can also try heating it up to get it to let go. It's been in there for a dog's age, and any road salt drop that got in there can make it mighty tough to get off. When you put the new one on, be sure to only use force on the inner race. It should be a fairly tight fit. I'm not sure what is called out in the design, but a slip fit would be good enough for it. I seem to remember a slip fit. I should check mine one day. It's been many many years since I put u-joints in this truck.

[ncpetersc]

Originally Posted by Steeveedee

Try leaving the tension on it overnight and the blasting agent will likely loosen it up. Do you have a propane torch? If you have the support off the bearing, you can also try heating it up to get it to let go. It's been in there for a dog's age, and any road salt drop that got in there can make it mighty tough to get off. When you put the new one on, be sure to only use force on the inner race. It should be a fairly tight fit. I'm not sure what is called out in the design, but a slip fit would be good enough for it. I seem to remember a slip fit. I should check mine one day. It's been many many years since I put u-joints in this truck.

Pretty much what I did, but nothing magical happened overnight. I don't have a torch, might consider buying a small one at Home Depot or something. Gonna keep at it for now. I am very sore today... lol. I think the worse part is that I am working on it on the ground basically. I don't have bench enough for a driveshaft at the moment.

Thanks

[Steeveedee]

I know that working on the ground gig. That's how I've been doing it since I quit working as a mechanic. Maybe try cranking up the force on the bearing. Worst that happens is yo break the bearing and have to cut the inner race with a Dremel cutoff wheel. If that's what happens, cut into the race just enough to get a chisel into it and give it a good smack. Been there with that. too!

[BRL]

Originally Posted by stsalvage

Remember to mark the drive shafts ends the way you took it apart.If you clock it wrong it will vibrate like a mother

Not meaning to interrupt, but long ago a friend was towing his car with a Turbo-400 from Mississippi to CA. and I removed the driveshaft thinking that the trans. would be turning inside, but no pump would be lubing it on that long journey.

I then realized after he left that I hadn't marked the driveshaft for realignment, and mentioned it to someone.

Guy said it didn't matter, as the driveshaft itself is balanced so it will remain that way no matter how it's re-orientated.

Well, the friend didn't complain of vibration after he re-installed it in CA. so...?