Infraction Infraction sounds like a chainsaw

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sstewardson

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Hi. I got a second hand infraction a few days ago. It’s pretty much new however its quite loud and when you get over about 60% throttle it sound like a chain saw.

I’ve had a good look and the rear driveshaft appears to be slightly bent which I think it causing the car to vibrate at high speed possibly causing the noise.

Has anyone else experienced this or know what it could be if it’s not the driveshaft?

I have also noticed quite a bit of metallic dust around the pinion is that normal?

I have attached a video below and a pic of the dust around the pinion.

https://vimeo.com/791983093/

3F1BD41E-1649-4447-8D27-503BA85B4A85.jpeg


After posting this and waiting for it to be approved I’ve noticed there is no grub screw in the pinion so it’s been moving back and forward. This is probably what’s caused the dust and could be contributing to the noise.
 
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Hi. I got a second hand infraction a few days ago. It’s pretty much new however its quite loud and when you get over about 60% throttle it sound like a chain saw.

I’ve had a good look and the rear driveshaft appears to be slightly bent which I think it causing the car to vibrate at high speed possibly causing the noise.

Has anyone else experienced this or know what it could be if it’s not the driveshaft?

I have also noticed quite a bit of metallic dust around the pinion is that normal?

I have attached a video below and a pic of the dust around the pinion.

https://vimeo.com/791983093/

View attachment 272470

After posting this and waiting for it to be approved I’ve noticed there is no grub screw in the pinion so it’s been moving back and forward. This is probably what’s caused the dust and could be contributing to the noise.

Hello and welcome!

I was going to say gearing, but you found part of the issue. Get the set screw back in and make sure it has a good mesh as well.

Infraction all metal gears do have a certain sound, loud. When I change out my pinions, it sounds different each time until I run a pack through it to wear it in. Did not sound too bad to me but hard to tell...

Never hurts to check F/R diff to make sure it's seated well and shimmed to prevent any side-to-side movement. As for the center diff, if you have removed it, make sure that the top plate over the center diff is fully down. It has a little cavity it sits in, and I have seen myself not fully seat it, so it has the center diff bearings completely locked in and no movement.

I do not think this is your issue, but I am not a fan of the plastic center diff "H" mount. I always change it over to aluminum to ensure no movement. Check the center diff, and it's housing over well also.

Bash on (y)

BTW - Blow some dust off, and a little housecleaning does help in the event of small rocks, sand, or pebbles are in areas we cannot see in the drivetrain (y)
 
Sounds about the same as my V2 before I changed the pinions a week or so ago. Was actually about to post about noisy drivetrains on here before I saw this thread. Put a 21 to replace the 18t in my mojave then decided to put the 18 in the 'fraction. Both rigs now seem louder on the bench than before the swap but based on the Talbot vids about gear mesh and having a tick of play between teeth I know I got the mesh right.
Along with getting the dirt and grime Parcou mentioned, maybe invest in a set of those inner fender from Scorched. I have them on mine and they help a ton keeping stuff out of the chassis/away from the gears.
 
Went to adjust the mesh and both the engine Mount bolts are stripped. Ffs here we go again. Came away from the big rock because I spent more time working on it that bashing it and now this happens lol
 
That sound is normal, all 6S sound like that. Might be a little louder due to your pinion, but honestly I doubt that. It's metal on metal gearing.

Yes, your driveshaft is bent, suggest getting a spare and learn how to straighten them out. Happens when you hit a curb or similar. You can always go way out and buy a carbon shaft, but honestly for bashing its overkill and they will shatter on impact if it's hard enough.
 
Went to adjust the mesh and both the engine Mount bolts are stripped. Ffs here we go again. Came away from the big rock because I spent more time working on it that bashing it and now this happens lol
Awe im sorry man, don't get to discouraged, once set up right this rig will always serve you very well and unless you crash will have 0 times you work on it, again unless a bad crash.
 
Stripped screws.... If you have an air compressor, pick up a pneumatic engraver from amazon. I think they're about $70 or so. I'm a toolmaker by trade and work on a ton of automation at a Ford plant and the engraver I keep in my toolbox has gotten me out of so many jams when a line is down to get a screw out instead of having to drill out, re-tap or helicoil a machine. I've used that thing on screws as small as M2.5 all the way up to M10s. I know they have electric ones also but they don't seem to "hit" the screw as hard as the air ones do.
 
Or a Dremel & a skinny cutoff wheel if you have one
Yeah, I think that would work much better. I think it would be difficult to make a single, consistent groove with a hacksaw.

Welcome, and good luck with the repairs! Hopefully once you get past some initial "teething" issues, it will settle down and require less wrenching.
 
Ok so an update. I have secured the pinion however when I get to full throttle with the body off the pinion and spur are making sparks but only at full throttle. Anyone know what this could be or also get this?

Now I have replacement bolts I am going to remove the motor and have a look but just thought I’d ask
 
I was thinking of making a line with a hacksaw and using a flat head screwdriver to undo it.
I used a Dremel tool with a small cutoff wheel instead of a hacksaw and put the motor mount in a drill vise. this worked very well for me.
 
Ok, that's a new one, sparks from pinion/spur is not normal.

Do you have a good mesh and are they actually straight or is the motor at a slight angle (motor mount might be bent). Both should be dead on straight.
 
Ok, that's a new one, sparks from pinion/spur is not normal.

Do you have a good mesh and are they actually straight or is the motor at a slight angle (motor mount might be bent). Both should be dead on straight.
Motor looks really straight. I’ll get it out and see if there is anything wedged in there that I can’t see
 
I have found a small piece of metal next to the pinion which was trapped. This must be what was sparking. Is the melted metal normal? Looks like a coating
C6E1A7C6-9F9D-4194-866D-AEBAE6ECE7AE.jpeg
 
I have found a small piece of metal next to the pinion which was trapped. This must be what was sparking. Is the melted metal normal? Looks like a coating View attachment 273334
That is not normal: that piece of metal, which looks to be the grub screw that holds the pinion on to the motor shaft, has gouged out the motor mount severely. If this hadn't been a Safe D pinion, the pinion gear would have come completely off by now.
 
No, not normal and no idea what it could be. Looks like it's hitting the inner side of your pinion. I'd take a dremel and remove it. The mount is aluminum and that won't spark.
 
That is not normal: that piece of metal, which looks to be the grub screw that holds the pinion on to the motor shaft, has gouged out the motor mount severely. If this hadn't been a Safe D pinion, the pinion gear would have come completely off by now.
That’s exactly what it is! I’ve removed it now and put on the larger pinion. All looks okay :)
 
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