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tberger06
04-24-2017, 12:09 PM
Hey everyone, my engine recently started vibrating more than normal. I do have solid rubber motor mounts and I put a Powerbond (Dayco) harmonic balancer on it back at the end of December and it has run pretty smooth since. Within the past week the engine vibrations have gotten noticeably worse (mostly between 2,000-3,000 rpm) and you can feel it shake the whole car when stationary and even driving.

I changed the oil yesterday and checked the balancer bolt, nothing seemed out of the ordinary, but it still vibrates pretty good. I haven't noticed any lack of power or drop in fuel mileage either.

Any thoughts on what to check next? I'm thinking maybe the balancer is already shot?

The car is an 89 XR7.

KMT
04-24-2017, 12:19 PM
Auto or manual trans?

Messed with the plugs/wires/coil recently?

tberger06
04-24-2017, 12:23 PM
It's a 5-speed manual and no codes are being thrown. I have not messed with the ignition system.

KMT
04-24-2017, 01:11 PM
you can feel it shake the whole car when stationary and even driving.

If that means regardless of clutch depressed or not, I'd suspect the balancer, but we're told the PBs don't fail - did you check the center bolt? Might need to pull it to see if the key sheared, etc.

tberger06
04-24-2017, 01:27 PM
If that means regardless of clutch depressed or not, I'd suspect the balancer, but we're told the PBs don't fail - did you check the center bolt? Might need to pull it to see if the key sheared, etc.

I held the clutch in and put it in gear while sitting in the driveway and it didn't change the vibration at all.

If the key sheared, wouldn't that throw off my timing as well?

KMT
04-24-2017, 02:00 PM
Yes, perhaps adding to engine vibrations, but the computer might be trying it's best to mask timing change, depending on how minor/major.

The only way to know/eliminate as suspect, is to manually time the engine using the balancer marks, etc. while validating center bolt, etc.

See this previous thread for discussion: http://www.sccoa.com/forums/showthread.php?116705-Harmonic-balancer-breakage-Does-the-main-bolt-break-first

Might be a pressure plate issue/thrown weight. Might be a trans mount failure. Might be motor mounts...if you watch the engine, does it rock badly when someone revs it in neutral?

Creighton
04-24-2017, 08:00 PM
Are K-member bolts to 100 ft/lb torque? E-18 female socket required.
All suspension bolts checked to factory spec is wise as well.

Creighton

sam jones
04-24-2017, 08:06 PM
Good afternoon


I would check the harmonic balancer pulley bolts. Re-torque the four bolts. Start car and check for a wobble. I have had a bolt back off causing the same issue.



Good Luck.

tberger06
04-24-2017, 09:23 PM
I'll get it up on a lift and check all that stuff hopefully this weekend. Thanks for all the suggestions.

tberger06
04-29-2017, 07:12 PM
I removed the harmonic balancer today and nothing was wrong. The balancer, crank, and key were all fine.

We put the car up in the air on the lift with my friend inside and had him start it up and hit the throttle while I looked at it from underneath. The flywheel turned perfectly straight.

The motor mounts are in great shape and the engine does not rock side to side under throttle.

With the car off we turned it over by hand and looked at all the clutch bolts. They were all present and none had backed off. We also stuck a flexible magnet down inside near the bottom of the flywheel to see if there were any balancing weights or pieces of metal, but the magnet came out clean.

The only possibility left that I can think of is a loose flywheel bolt (not very likely since it doesn't have any wobble), the flywheel became unbalanced somehow (but how?), or something internal to the engine is out of whack (I'm not really sure what that would be though). It still has no codes and runs great.

I'm debating on just driving it until something gives out.

sam jones
04-30-2017, 12:53 AM
Good evening

If you found no defects at the engine next step would be the drive train. Specifically the drive shaft and or bad transmission mount. Do you feel a slight "bang" when in reverse? If so check the four drive shaft mount bolts for torque. They have been known to back off. If no defects with the transmission mount/drive shaft bolts suspect driveshaft universal joint.

Have you see this link: http://www.sccoa.com/forums/showthread.php?122418-vibration-yes-I-searched-first




Good Luck.

tberger06
04-30-2017, 11:18 AM
Good evening

If you found no defects at the engine next step would be the drive train. Specifically the drive shaft and or bad transmission mount. Do you feel a slight "bang" when in reverse? If so check the four drive shaft mount bolts for torque. They have been known to back off. If no defects with the transmission mount/drive shaft bolts suspect driveshaft universal joint.

Have you see this link: http://www.sccoa.com/forums/showthread.php?122418-vibration-yes-I-searched-first




Good Luck.

This happens when stationary and out of gear, so I can eliminate anything after the transmission as a possible cause.

sam jones
04-30-2017, 10:00 PM
This happens when stationary and out of gear, so I can eliminate anything after the transmission as a possible cause.

Good evening


Sorry I did not understand the condition. You might want to try troubleshooting the drive/accessory system. Disconnect the belts one at a time start the car and see if this will eliminate the vibration issue.

XR7 Dave
05-09-2017, 06:58 AM
Anything can fail. BHJ balancers have failed in the past also. I haven't see the steel hubs break, but the elastomer can fail and I've seen them out of round.

But more on point - Never seen a keyway fail. Ever. It's a long key with tons of engagement. Probably the last thing I'd ever suspect, particularly on an iron balancer.

If the ring turns, it can only do so if the elastomer fails, but that doesn't affect timing as the reluctor ring is bolted to the hub, not the ring. The only way timing can be affected is if the hub shears. Never seen that on anything other than an aluminum hub. Ever.

The hub and ring are both neutral balance. If one DID shift, it would not likely noticeably affect balance, however if something did happen severe enough to cause that to happen, you have much bigger problems than a failed balancer. The balancer would most likely be the victim in this case, not the cause. You can check the elastomer for resilience. They get work hardened over time which is another reason why factory balancers tend to fail - the OE rubber gets rock hard, cracks, and literally starts to fall out. PB balancers are made by Dayco, yeah the worlds largest HB manufacturer. I've spoken with their engineers, they claim their elastomer will literally pretty much never harden. Better material than 1989-95 OE.

That being said, a broken mount could transmit more vibration into the car, or anything binding the motor (a wrench stuck under the oil pan, who knows?). But if you've eliminated all external factors, it could be pointing to an internal engine problem - bent connecting rod or crankshaft. That is something I've seen many times.

tberger06
05-09-2017, 09:00 AM
I think I'll get a replacement balancer to put on it. This way I can eliminate the balancer if it still vibrates with the new one.

In the event it still vibrates, I guess I'll need to pull the engine and tear it down. My concern is the engine only has 23k miles on it after a rebuild by Jasper, which seems way too soon.

KMT
05-09-2017, 11:08 AM
But more on point - Never seen a keyway fail. Ever. It's a long key with tons of engagement. Probably the last thing I'd ever suspect, particularly on an iron balancer.


Thanks for confirming that won't happen on our engines.

Ken

XR7 Dave
05-09-2017, 12:14 PM
I think I'll get a replacement balancer to put on it. This way I can eliminate the balancer if it still vibrates with the new one.

In the event it still vibrates, I guess I'll need to pull the engine and tear it down. My concern is the engine only has 23k miles on it after a rebuild by Jasper, which seems way too soon.

Well that may be a big part of your problem. Jasper engines are notorious for breaking crankshafts due (possibly/probably) to how they grind the rod journals on the crank. Do a search on here, you'll see what I mean. Yes i know this sounds like a commercial for my engine building services, but it's not. I'm way too busy already. I'm just speaking from experience. Hope your problem is a faulty balancer.

XR7 Dave
05-09-2017, 12:16 PM
Thanks for confirming that won't happen on our engines.

Ken

It's not that it can't or won't happen, I just said it's highly unlikely and I don't think it matches the type of problem being experienced here.

DrFishbone
05-09-2017, 01:17 PM
Well that may be a big part of your problem. Jasper engines are notorious for breaking crankshafts due (possibly/probably) to how they grind the rod journals on the crank. Do a search on here, you'll see what I mean. Yes i know this sounds like a commercial for my engine building services, but it's not. I'm way too busy already. I'm just speaking from experience. Hope your problem is a faulty balancer.

I don't know that Jasper rebuilt the engine I was using (got it from someone else), but it was definitely rebuilt by a big company as evidenced by a custom tag glued to the side of the block w/serial number. I broke that crank last fall..should be out of the car soon.

I've not heard of a problem like this with the Powerbonds, but many of the BHJ's did not have the crank pulley holes tapped deep enough. The bolts would snug up and even hold the pulley fairly securely against the balancer. I'd check to make sure your pulley is indeed securely fastened to the balancer. Maybe run the bolts down w/o the pulley and see how far they really do go.

tberger06
05-17-2017, 09:02 PM
I ordered a new Powerbond balancer and installed it today...and the engine still has vibrations. I even took off serpentine belts one a time to eliminate pulleys/accessories/supercharger and the vibration was still there.

I think I'll just drive it back and forth to work and see if things get worse.

I now have an extra Powerbond balancer if anyone is interested.

sam jones
05-17-2017, 11:58 PM
Good evening


The vibration is still there and troubleshooting has eliminated the following failures:

- Harmonic balancer.

- Accessories (water/ power steering pumps, A/C compressor, alternator, supercharger, pulleys/tensioners)

- Transmission/drive train.

- Engine/transmission mounts.


I would now troubleshoot the ignition system as suggested by KMT in post #2. Coil pack, plugs, and wires for a miss fire.

If you have not already, check (if equipped) the EGR for carbon blockage and engine connections for vacuum leaks.

Check the canister purge valve solenoid vacuum line and rubber hose connector for damage.



Good Luck.

tberger06
05-20-2017, 12:06 AM
I checked all the plug wires, plugs, and coil pack. The plug wires were all between 5-10k ohms. The coil pack was 11.4k ohms for all three cylinder pairs. All the spark plugs looked good as well.
https://c1.staticflickr.com/5/4203/34634531441_fd223a7c08_z.jpg (https://flic.kr/p/ULx2xP)

I do not have an EGR anymore.

What is a good way to check for vacuum leaks?

Also, where is the canister purge valve solenoid located?

KMT
05-20-2017, 12:19 AM
Gap(s)?



What is a good way to check for vacuum leaks?

Smoke test


Also, where is the canister purge valve solenoid located?

Inside the pass. side fender, wedged between the cold air snorkel and the tub/body. Not fun to try to get to/work on.

sam jones
05-20-2017, 03:41 AM
I checked all the plug wires, plugs, and coil pack. The plug wires were all between 5-10k ohms. The coil pack was 11.4k ohms for all three cylinder pairs. All the spark plugs looked good as well.
https://c1.staticflickr.com/5/4203/34634531441_fd223a7c08_z.jpg (https://flic.kr/p/ULx2xP)

I do not have an EGR anymore.

What is a good way to check for vacuum leaks?

Also, where is the canister purge valve solenoid located?



Good evening


Could have a problem with a coolant leak based on the last 2 set of spark plugs to the right of the picture. Maybe due to the picture angle/light but the spark plugs white insulator firing tip is very clean. Poor engine cooling system efficiency (leaking head gasket) and or intake manifold leak. Fuel injector o - rings could also be damaged causing an air leak.



As far as vacuum leak test as KMT suggest smoke test is the best method. Another means you can use the soap/water bottle squirt application. Listen for a change in rpm and or a "hissing" sound with bubbles. There are many other ways (like propane) which you can find searching the forum or You Tube videos.

tberger06
05-20-2017, 12:40 PM
Gap(s)?




Smoke test



Inside the pass. side fender, wedged between the cold air snorkel and the tub/body. Not fun to try to get to/work on.

Gaps are as follows (left side going up, then right side going up referencing picture above):
.047 .051 .054
.047 .049 .048

I'm guessing they should all be around .047 to .048 gap?


Good evening


Could have a problem with a coolant leak based on the last 2 set of spark plugs to the right of the picture. Maybe due to the picture angle/light but the spark plugs white insulator firing tip is very clean. Poor engine cooling system efficiency (leaking head gasket) and or intake manifold leak. Fuel injector o - rings could also be damaged causing an air leak.



As far as vacuum leak test as KMT suggest smoke test is the best method. Another means you can use the soap/water bottle squirt application. Listen for a change in rpm and or a "hissing" sound with bubbles. There are many other ways (like propane) which you can find searching the forum or You Tube videos.

The insulator tips in the picture look misleading. All of them are darkened, but most are only darkened on one half and still fairly white on the other half.

KMT
05-20-2017, 01:44 PM
I'm guessing they should all be around .047 to .048 gap?


Factory specs should be on a sticker on the header panel, under the hood. .052 ~ .056, as I recall, so, say .054" - Sorry if I missed it...how many miles on them? Did you look close at the ceramic around the tips for cracks?

If you haven't put them back in yet, I'd replace w/new, stock spec.

But if you've upped the boost, then we're told to reduce the gap a bit, depending on. Whatever gap, I'd set them all the same.

This is more about housekeeping at this point, tho... Assuming the firing order is valid, I don't see anything obvious from the plugs that would suddenly generate a new vibration.

XR7 Dave
05-20-2017, 02:23 PM
Normally those would be gapped .045"

Since you have plugs out, do a compression test. Be sure to block the bypass and TB open and disable the fuel injectors while doing it.

tberger06
05-20-2017, 04:40 PM
Normally those would be gapped .045"

Since you have plugs out, do a compression test. Be sure to block the bypass and TB open and disable the fuel injectors while doing it.

I did the computer cylinder balance test back when this first started and it reported back a 90 meaning I passed. Will a manual compression test be that much better?

tberger06
08-05-2017, 06:44 PM
After letting the car sit for a few months, I'm taking the easy way out and will just drive it as is.

tberger06
08-23-2017, 08:50 PM
Today I decided to check the coil pack again, and this time I pulled plug wires one at a time while it was running. All of them had spark, but when I pulled #3 it didn't seem to change how it was running.

This leads me to believe that it could either be the spark plug (the wire has already been tested and is good) or the injector. I do not believe it is the spark plug because I visually checked them all when I pulled them a while ago, and they all looked similar (as you can see in the picture above) and they were all re-gapped.

I'm leaning towards the injector going bad. The car has plenty of power when in the throttle, but the vibration is most apparent when idling or light throttle cruising. Maybe the injector isn't spraying under light load, but sprays when under heavy load? I haven't noticed any drastic change in fuel mileage...if anything it might have gone up slightly.

I plan to pull all the spark plugs (again :() and verify they all spark.

Is there a good way to test the injectors without pulling them? I have extras that I can swap in, but I'd like to avoid that unless necessary.

sam jones
08-23-2017, 10:20 PM
Good evening


You could ohms test the injectors without removing them to see if they are in limits. See attachment.


https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwi_18KF5O7VAhUV32MKHWX2Cz0QFgg0MAI&url=https%3A%2F%2Fwww.2carpros.com%2Farticles%2Fho w-to-test-a-fuel-injector&usg=AFQjCNFtj6yaFpP2OSv4ZLZnThX1VK56RA



Have you ohms checked and or swap plugs wires to eliminate that issue? See attachment.


https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwjYt-GY5u7VAhUHqFQKHQGqCIwQFggrMAE&url=https%3A%2F%2Faxleaddict.com%2Fauto-repair%2FChecking-spark-plug-wires-using-two-simple-strategies&usg=AFQjCNHoLz_nCMBqEj9vTlqvP_HbBibuFw

tberger06
08-27-2017, 06:43 PM
Good evening


You could ohms test the injectors without removing them to see if they are in limits. See attachment.


https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwi_18KF5O7VAhUV32MKHWX2Cz0QFgg0MAI&url=https%3A%2F%2Fwww.2carpros.com%2Farticles%2Fho w-to-test-a-fuel-injector&usg=AFQjCNFtj6yaFpP2OSv4ZLZnThX1VK56RA



Have you ohms checked and or swap plugs wires to eliminate that issue? See attachment.


https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwjYt-GY5u7VAhUHqFQKHQGqCIwQFggrMAE&url=https%3A%2F%2Faxleaddict.com%2Fauto-repair%2FChecking-spark-plug-wires-using-two-simple-strategies&usg=AFQjCNHoLz_nCMBqEj9vTlqvP_HbBibuFw

I did the screwdriver trick to listen to the injectors and they all sounded fine. I went ahead and replaced the spark plugs, plug wires, and coil pack. I ran the computer cylinder balance test and it came back good. The damn thing still vibrates and doesn't have any codes...I'm at a loss

TBirdSC89
08-28-2017, 01:49 AM
I did the screwdriver trick to listen to the injectors and they all sounded fine. I went ahead and replaced the spark plugs, plug wires, and coil pack. I ran the computer cylinder balance test and it came back good. The damn thing still vibrates and doesn't have any codes...I'm at a loss

Just gonna throw my 2 cents in. I had a 95 sc auto that had bad vibration issues when sitting at a light. I checked everything like you did. unfortunately my balancer broke off while driving. the balancer bolt had broken off the engine. have you removed the center balancer bolt?it threw off my timing. with it running at idle in my driveway nothing vibrated or moved only when in gear.
if its not the balancer or bolt have you checked the driveshaft and all connections?
gotta say visually my balancer did not seem to move or vibrate at all when seeing the engine running. but that bolt sheared right off. just hope if that is the problem you catch it in time.

sam jones
08-28-2017, 09:10 AM
Good morning

It appears that overall health of the engine and transmission is good. I would take a look at the crank shaft pulley and bolts. Every DAYCO harmonic balancer installation I've done required a slight enlargement of one of the 4 crankshaft pulley mounting holes. But too much will cause the pulley to shift in rotation and a vibrating engine.

See attachments.

http://www.sccoa.com/forums/showthread.php?118747-BHJ-Broken-crank-pulley-bolts/page2

http://www.sccoa.com/forums/showthread.php?133244-balancer

http://www.sccoa.com/forums/showthread.php?132979-bad-harmonic-balancer-or-bad-rod-bearing

http://www.sccoa.com/forums/showthread.php?135586-Dorman-Harmonic-balancer-Not-sure-what-to-do/page2

You might find the bolts have "necked down" and or slightly bent.