Transaxle issue?, Feels like I'm running over speed bumps |
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Transaxle issue?, Feels like I'm running over speed bumps |
rtalich |
Apr 17 2015, 10:18 AM
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#1
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Member Group: Members Posts: 279 Joined: 25-September 06 From: Bellevue, WA Member No.: 6,913 Region Association: None |
Issue just started last night. Just starting out in first gear while slipping the clutch. Once clutch engages at lower RPMs it felt like I was rolling over speed bumps. At faster speeds it seemed fine. Now it is starting to happen more frequent but only at lower RPMs. I have not had a chance to diagnose yet. Anything in particular come to mind?
Thanks Rob |
rtalich |
Apr 27 2015, 09:13 AM
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#2
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Member Group: Members Posts: 279 Joined: 25-September 06 From: Bellevue, WA Member No.: 6,913 Region Association: None |
Finally had a chance to work on the car this weekend. Thanks for all your help guys! It was the rubber motor mounts. Both of them were sheared in half!!
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stugray |
Apr 27 2015, 09:52 AM
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#3
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
Finally had a chance to work on the car this weekend. Thanks for all your help guys! It was the rubber motor mounts. Both of them were sheared in half!! That is great that you found them! When I took my engine out the last time I found both of mine broken as well. However, the broken motor mounts should not cause the behavior that you describe all by themselves (more like a symptom than root cause) Dont be too surprised if you find that the problem is still there after you replace them. I would expect broken motor mounts to show thenselves more when starting/stopping or shifting, not driving smoothly over level ground. Maybe I misunderstood your description of the problem. |
Dave_Darling |
Apr 27 2015, 07:48 PM
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#4
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914 Idiot Group: Members Posts: 15,048 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
However, the broken motor mounts should not cause the behavior that you describe all by themselves (more like a symptom than root cause) ... No, they will cause that behavior. BTDT. The whole drivetrain pivots up and down, slamming the mount brackets against the motor mount bar. WHAM WHAM WHAM WHAM! Most prevalent in 1st gear when the drivetrain is putting the most torque down. --DD |
stugray |
Apr 27 2015, 11:19 PM
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#5
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
No, they will cause that behavior. BTDT. The whole drivetrain pivots up and down, slamming the mount brackets against the motor mount bar. WHAM WHAM WHAM WHAM! Most prevalent in 1st gear when the drivetrain is putting the most torque down. --DD So do you think the engine is "hopping" up and down when it does this or twisting/rocking? I remember driving my fathers TR4 that had a broken motor mount. The symptom was: when making a right turn, the steering would not self center. Because the engine was leaning up against the steering shaft - DOH! Edit - just thought about this. If both axles are torquing to push the car forward, then the engine is trying to raise upwards in the front. So with a high HP engine, the front mounts need to hold the engine DOWN. |
Dave_Darling |
Apr 28 2015, 08:05 PM
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#6
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914 Idiot Group: Members Posts: 15,048 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
So do you think the engine is "hopping" up and down when it does this or twisting/rocking? Hopping. The whole thing pivots around the drive axles, lifting the front up. It gets to a certain point and then falls--possibly because the wheels are indeed turning. The motor falls back down onto the mounts. Then the process starts over again. The sound and feel was way too violent for it to just be rocking. --DD |
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