Compression test results and running warm

[electrorc]

Well, that eliminates alot. The only things left are the transmission, Drive shaft, Differential and the Axels.

I would look at two areas. The drive shaft and the Axels. A bad wheel bearing on one of the Axels could cause a vibration so I would look for one or both of the Axel ends to be loose when you try to wiggle it or make noise when it rotates though this could be hard to detect.

Good luck and keep trying to narrow it down.

Cool. I wouldn't be too surprised if I do have a bad wheel bearing on the left rear--it definitely makes a sort of loose, rattling sound as it spins. I'm trying to decide if I want to spend the money to fix that or just save more and upgrade to an 8".

I'm getting tired of this 2.77 transmission and old clutch, so I'll hopefully be going back to the 3.03 here in a couple days. I'm going to check into getting the driveshaft balanced first though.

 

[woodbutcher]

Hi electrorc.Good insurance to fix that axle bearing.If you have never lost an axle from a siezed bearing you are in for a heck of a ride.Had an axle snap because of a failed bearing at about 40 mph.Took an end loader to clean off the front seat and floorboards.Had just exited I-95 where I had been running about 75 mph.Now THAT would have been an adventure.
Good luck.Have fun.Be safe.
Leo

 

[Frankenstang]

Now I'm noticing that if I put it in neutral on the highway the vibration is largely still there.

If this is still the case, that would suggest a non-driveline vibration...rear axle bearings, front bearings, suspension, tires, etc. Have you tried simply rotating the tires? Do you have spare? If so you could try swapping it for one tire at a time. A lost balancing weight could cause a decent vibration, but so would a separated belt...and those can be harder to id. Tire swapping would rule out tire issues.

As far as the miss, if I followed correctly, you did a leakdown on one head then put on another? Did you do a leak down test on the replacement head? If not that is the first thing I would do.

I seem to recall your pushrod problem, bent and broken push rods as you mentioned. Did you ever determine what caused it on the old engine? You said you did the push rods on the rebuild...any chance a wrong size one got slipped installed on #2 cylinder by mistake? Again, if you haven't already done it, I do another leak down test. A constant flow of air as you described on the first head from a non-seating valve (even barely non-seating) will make a heckuva miss. Good luck

 

[electrorc]

Hi electrorc.Good insurance to fix that axle bearing.If you have never lost an axle from a siezed bearing you are in for a heck of a ride.Had an axle snap because of a failed bearing at about 40 mph.Took an end loader to clean off the front seat and floorboards.Had just exited I-95 where I had been running about 75 mph.Now THAT would have been an adventure.
Good luck.Have fun.Be safe.
Leo

Yeah, I'll definitely be fixing it one way or another at some point, hopefully soon. Doesn't sound like a good thing to have fail, by any means...

If this is still the case, that would suggest a non-driveline vibration...rear axle bearings, front bearings, suspension, tires, etc. Have you tried simply rotating the tires? Do you have spare? If so you could try swapping it for one tire at a time. A lost balancing weight could cause a decent vibration, but so would a separated belt...and those can be harder to id. Tire swapping would rule out tire issues.

I'm pretty sure I did rotate the tires last year, but now I can hardly remember what difference it made. I don't have a definitely good spare. I have another set of wheels and tires, but the tires are pretty old so I don't want to take it on the highway with them. I'll try swapping them around again though.

As far as the miss, if I followed correctly, you did a leakdown on one head then put on another? Did you do a leak down test on the replacement head? If not that is the first thing I would do.

Correct. I didn't do a leak down on the second head, just the compression check (which was fine). The air compressor isn't at my house, so I have to wait a bit before I can use it again.

I seem to recall your pushrod problem, bent and broken push rods as you mentioned. Did you ever determine what caused it on the old engine? You said you did the push rods on the rebuild...any chance a wrong size one got slipped installed on #2 cylinder by mistake? Again, if you haven't already done it, I do another leak down test. A constant flow of air as you described on the first head from a non-seating valve (even barely non-seating) will make a heckuva miss. Good luck

Nope, never figured out the cause. The shop just told me it was probably over-revved at some point, but I don't know. I think I double-checked all the pushrods at some point too.


I swapped back to the 3.03 trans and 9" clutch yesterday. The 8.5" clutch actually had a broken spring when I pulled it out--whoops. That would explain the change in the pedal feel a couple weeks ago though. Sadly I think I did something wrong in the swap... my clutch is really stiff and the vibration got lots worse. This car and I are definitely not getting along.

 

[Frankenstang]

Any luck William?

Correct. I didn't do a leak down on the second head, just the compression check (which was fine).

Well that's good news. Sounds like the head swap got your compression numbers back in line. I saw this on your blog...
"The engine doesn’t shake quite so badly at idle now, but still does some. I just performed a compression test though, and all of my cylinders are back where they should be—between 165 and 175 psi. So that’s good at least."

How "bad" is this vibration? Are we talking very noticeable shaking, or more subtle? You mentioned being able to notice it most when you've got your hand on the shifter...so wondering just how strong the vibration is.

I swapped back to the 3.03 trans and 9" clutch yesterday. The 8.5" clutch actually had a broken spring when I pulled it out--whoops. That would explain the change in the pedal feel a couple weeks ago though. Sadly I think I did something wrong in the swap... my clutch is really stiff and the vibration got lots worse. This car and I are definitely not getting along.

So what parts, if any are you re-using when swapping between the 2.77 and the 3.03? The bell housing should obviously be different, as I'm not aware of one that covers both. That can also mean a different throw out bearing fork/arm. You could probably use the 3.03 throwout bearing itself on the 2.77, but don't think vice versa will work. Also, the pilot bushing/bearing is different IIRC, as are the disc and pressure plate. Are you swapping over all these related parts when you go from one to the other?

How about a couple other basic things as well, with regard to the vibration, motor mounts,
transmission mount, etc? Good luck!

 

[Frankenstang]

I re-read your first post where you originally described the shaking to be very noticeable with the 3.03..."would shake the whole car. You could feel it very obviously in the seats and shifter". Sounds like it's not nearly as bad when you were running the 2.77, but not cured :

One note on the tire swapping...IIWIYS I'd try swapping one known good wheel & tire with one existing one. If it didn't cure the vibration then try swapping swapping the next existing tire. If it's something like a bad tire; out of balance, seperated tread, etc...rotating the existing tires would just move the problem around.

I'm sure when you track down the source of the vibration it will turn out to be something simple, as it usually does

 

[electrorc]

Thanks for the replies Frankenstang

Any luck William?
Well that's good news. Sounds like the head swap got your compression numbers back in line. I saw this on your blog...
"The engine doesn’t shake quite so badly at idle now, but still does some. I just performed a compression test though, and all of my cylinders are back where they should be—between 165 and 175 psi. So that’s good at least."

How "bad" is this vibration? Are we talking very noticeable shaking, or more subtle? You mentioned being able to notice it most when you've got your hand on the shifter...so wondering just how strong the vibration is.

Not really any luck, no. Just been driving it (and broke 5000 miles since the rebuild too!). I personally consider the vibration pretty bad, especially with the 3.03 in it now. At idle, the engine is very noticeably shaking, and will shake the whole car a little bit here and there. On the highway, it's really strong in the shifter (hand starts to feel funny after awhile if you leave it on it, if that helps?). With the 3.03, you can feel it a little in the seats and trans tunnel, and things are definitely rattling around a bit sometimes. I'm noticing it more in the steering wheel with the 3.03 too. Run it on jack stands at 70 mph, and the vibration is about the same as it is on the highway. Shift into neutral on the highway and it's still there, but it does seem to decrease in intensity a little. Hold 2nd gear to over 3000 rpm, and it will start vibrating pretty badly too. With the 2.77, it was primarily in the shifter that you felt it (and the idle was the same as the 3.03's). Nobody that's been in it has really complained about it, but it's primarily just family that knows to expect it lol.

So what parts, if any are you re-using when swapping between the 2.77 and the 3.03? The bell housing should obviously be different, as I'm not aware of one that covers both. That can also mean a different throw out bearing fork/arm. You could probably use the 3.03 throwout bearing itself on the 2.77, but don't think vice versa will work. Also, the pilot bushing/bearing is different IIRC, as are the disc and pressure plate. Are you swapping over all these related parts when you go from one to the other?

Pretty much nothing is being re-used between the two. I did use an old pilot bushing when I had the 2.77 in it, but that was the correct 2.77 one--I just didn't have any luck getting a new, correct one for it. When I swap them, I use a different: pilot bushing, bellhousing, clutch fork, throwout bearing, flywheel, clutch, pressure plate, transmission mount, mostly different bolts, starter, and a different driveshaft. About all that stays the same is the engine, clutch linkage itself, and the rear-end.

How about a couple other basic things as well, with regard to the vibration, motor mounts,
transmission mount, etc? Good luck!

Hopefully I got a better description of the vibration up at the top of this post (I'm really not the best at explaining it, I know--but thank you for trying to follow!). Motor mounts were replaced (stock-style Anchor IIRC) with the rebuilt engine, and I have a new trans mount from the same time that I leave attached to the 3.03.

I re-read your first post where you originally described the shaking to be very noticeable with the 3.03..."would shake the whole car. You could feel it very obviously in the seats and shifter". Sounds like it's not nearly as bad when you were running the 2.77, but not cured

Correct. Definitely better with the 2.77, but still there a little bit.

One note on the tire swapping...IIWIYS I'd try swapping one known good wheel & tire with one existing one. If it didn't cure the vibration then try swapping swapping the next existing tire. If it's something like a bad tire; out of balance, seperated tread, etc...rotating the existing tires would just move the problem around.

Well I don't have any that I'm 100% sure are good and haven't lost a weight or something. They all just sat in my trunk or in the garage while I was doing all the work on the car (I stored it on the stock wheels and rather old tires). That is a good point though. I should check and see how much it is to for a shop to check the balance on them.

I'm sure when you track down the source of the vibration it will turn out to be something simple, as it usually does

Yes, I imagine it is something absurdly simple, and that's probably one of the most frustrating parts of this whole thing. Honestly, I'm about at the point where I just want to drive it like it is until I have enough money to make a bunch of changes to it (8" rear, new flywheel, maybe a T5, not totally sure yet...) and just hope that that fixes it lol. Going piece-by-piece and not getting it better is expensive, especially since there's a good chance these aren't the parts I want on the car (eg the wheels and tires). At the same time, I also want to know exactly which part has been driving me crazy and broke over the past year.

 

[Frankenstang]

Knowing that you're swapping out all the correct related clutch and tranny mount parts would seem to eliminate the possiblity of a mismatch causing the vibration (my first concern was that you might be using the same pilot bushing for both 2.77 & 3.03, but you've got that covered).

I personally consider the vibration pretty bad, especially with the 3.03 in it now. At idle, the engine is very noticeably shaking, and will shake the whole car a little bit here and there. On the highway, it's really strong in the shifter (hand starts to feel funny after awhile if you leave it on it, if that helps?). With the 3.03, you can feel it a little in the seats and trans tunnel, and things are definitely rattling around a bit sometimes. I'm noticing it more in the steering wheel with the 3.03 too.

So, when you say "at idle", I'm assuming you mean with car parked and the hood up you can see the engine shaking "very noticeably"?

With it being that much more noticeable with the 3.03 installed that would give me some concern for condition of that 3spd...input or main shaft bearings on that tranny.

However, at idle and in neutral, I would not expect internal problems with the gear box to induce much vibration to the engine itself. That would also seem to rule out, drive shaft balance, rearend or other suspension issues with regards to the 'idle' vibration at least. As you and others have mentioned, you may have more than one source of the vibrations.

Did swapping the heads and bringing the compression back up on #2 cure your miss, or put another way, how does it rev and feel in idle? (i.e. with the car parked and hood up, if you rap the throttle linkage by hand can you tell if the engine is still shaking excessively in the compartment?

I hesitate to mention this as it's not something easily checked with the engine in the car, but it has happened before where rebuilders have mixed up the #6 & #7 main crank bearings. You might be able to double check crank runout with the engine in the car, but I would first want to know that the ignition, valve train, etc are all in good working order...basically that you've eliminated the miss as a cause of vibration first.

It's a bit late to suggest this now, but if in the future you go back to the 2.77, I'd want to consider trying to run the engine without a tranny attached...just to be sure the engine itself is not the source of vibration.
EDIT: Considering that a harmonic balancer or flywheel issue could also be potential source of vibration.

Again, I'm hesitant to over emphasize something like the possible crankshaft bearing mixup, as the approach I prefer in chasing down an "elusive" issue, is avoiding going too many directions at once. So hope I haven't misdirected your diagnosing in that way. Good luck

 

[electrorc]

Sorry for taking awhile to get back to you Frankenstang. I haven't come up with too much new with it.

So, when you say "at idle", I'm assuming you mean with car parked and the hood up you can see the engine shaking "very noticeably"?

Correct. In neutral and idling, if you open the hood, you can see the engine shaking around a fair bit. A presumably cammed V8 Monte Carlo came in it at work and it's engine shook about like mine at idle... so maybe that's just sort of normal...

With it being that much more noticeable with the 3.03 installed that would give me some concern for condition of that 3spd...input or main shaft bearings on that tranny.

However, at idle and in neutral, I would not expect internal problems with the gear box to induce much vibration to the engine itself. That would also seem to rule out, drive shaft balance, rearend or other suspension issues with regards to the 'idle' vibration at least. As you and others have mentioned, you may have more than one source of the vibrations.

My thoughts all around as well. I have no idea what condition the 3.03 is in, as I purchased it off Craigslist and didn't do anything to it. I could see it contributing to the issue, but the engine or flywheel has to have some sort of issue as well I think to give me the shifter vibration with the clutch in and in neutral.

Did swapping the heads and bringing the compression back up on #2 cure your miss, or put another way, how does it rev and feel in idle? (i.e. with the car parked and hood up, if you rap the throttle linkage by hand can you tell if the engine is still shaking excessively in the compartment?

It really didn't seem to make much difference at all. The idle is still about the same from what I can tell, and I know revving it in neutral still results in a shifter vibration.

I hesitate to mention this as it's not something easily checked with the engine in the car, but it has happened before where rebuilders have mixed up the #6 & #7 main crank bearings. You might be able to double check crank runout with the engine in the car, but I would first want to know that the ignition, valve train, etc are all in good working order...basically that you've eliminated the miss as a cause of vibration first.

Interesting. I'd hope that the shop didn't mess that up, but who knows. I'm taking it that'd require pulling those main caps to check? I have synthetic in it right now so I don't want to drain it until oil change time.

It's a bit late to suggest this now, but if in the future you go back to the 2.77, I'd want to consider trying to run the engine without a tranny attached...just to be sure the engine itself is not the source of vibration.
EDIT: Considering that a harmonic balancer or flywheel issue could also be potential source of vibration.

Again, I'm hesitant to over emphasize something like the possible crankshaft bearing mixup, as the approach I prefer in chasing down an "elusive" issue, is avoiding going too many directions at once. So hope I haven't misdirected your diagnosing in that way. Good luck

I did briefly run the engine with no trans, both with the 8.5" flywheel setup and the 9". I really should've paid more attention to it when I did it, but I do remember it being at least a little smoother overall when revved. I'm not sure how much of that was a result of just having one less mounting point to the body though. Definitely should've recorded that or something--whoops.

I did wise up at least a tiny bit with this though. I realized I could swap my driveshafts between the 2.77 and 3.03 ones since it's just the slip yokes that are different. So I swapped slip yokes and I have the 2.77 shaft in now. I want to say it's a tiny bit better, but it's very inconsistent. On my way to work, I had lots of vibration, including in the steering wheel. It was the same as with the other shaft, basically. On my way home, it was still present, but much less noticeable. I didn't change anything during the workday on it. Weird...

I also checked my driveline angles, and those may be playing a part in the mess as well. My front u-joint has an operating angle of 1 degree, while the rear is about 4.5 degrees. Since those are supposed to be equal with 1 degree from what I've seen, and a max for either in the 3-4 degree range, mine aren't right.

So I think I'm going to look into some shims for the rear axle to get the u-joint angles better for a start. Beyond that, I'm not sure. There's not much cheap stuff left to change out lol. Maybe I'll try another balancer sometime too. But otherwise, I'm iffy on if I want to track it down piece by piece or just wait and change to a T5 and everything. Thanks for the help though, Frankenstang.

 

[69.5Mav]

Any Progress?