Problems with PC 7424XP

[1fastTbird]

To start, I have only used this machine less than 10 times since purchasing two years ago.

I have been correcting an F150 for the last couple days, and yesterday the machine developed a more intense vibration and noise as compared to the usual shaking and noises the PC's are famous for. It sounds like a bunch of rocks crashing together (again, much more so as compared to new) and power seems to slow down intermittently. It's was 95 degrees out yesterday and I was worried that it may have overheated.
I just went out and started to correct a new panel and the machine was smooth for all of 3 minutes and the problem is even more apparent today. I feel like it's about to die but before it does I am wondering if anyone has any ideas about what could cause this issue and if there is anything that I can service on the machine.
I have always used the proper gauge and length heavy duty extension cords.
To say that I am disappointed is an understatement.

[TFTADetail]

I've owned a few of the PC 7424 & 7424XP over the years and have never dealt with any of the shaking/noises you mentioned.

In your case it sounds like it's the motor. Could be wiring, but it's obviously only happening once it gets warmed up.

Time to do some shopping. Cheapest I've found is $119.00 all over the net.
Not sure where you're located but, this is a pretty good find.
Automotive Detailing Equipment Polisher Porter Cable 7424XP (http://fortcollins.craigslist.org/for/5030047465.html)

[builthatch]

To start, I have only used this machine less than 10 times since purchasing two years ago.

I have been correcting an F150 for the last couple days, and yesterday the machine developed a more intense vibration and noise as compared to the usual shaking and noises the PC's are famous for. It sounds like a bunch of rocks crashing together (again, much more so as compared to new) and power seems to slow down intermittently. It's was 95 degrees out yesterday and I was worried that it may have overheated.
I just went out and started to correct a new panel and the machine was smooth for all of 3 minutes and the problem is even more apparent today. I feel like it's about to die but before it does I am wondering if anyone has any ideas about what could cause this issue and if there is anything that I can service on the machine.
I have always used the proper gauge and length heavy duty extension cords.
To say that I am disappointed is an understatement.

what's the warranty on the XP? three years?

EDIT: "This Porter-Cable tool is backed by three-year limited warranty covering any defects due to faulty materials or workmanship (from the date of purchase). It's also covered by Porter-Cable's one-year free service contract, where Porter-Cable will maintain the tool and replace worn parts caused by normal use--for free."

[Kamakaz1961]

I have the PC I would check the gauge extension wire you are using. Make sure it is a heavy duty wire. On top of that have a surge protector too. IMO it appears your PC is heating up because of the different gauge or the cord you have it hooked up to is not heavy duty or too weak.

Try that 1st. My PC has been a workhorse and I have not experienced any problems with it. I have heard (with any DA for that matter) that you need the proper gauge cord as these machines take a lot of electricity to run.

IMO try that. As for the gauge maybe 14 or higher. Please don't quote me as I am gauge cord illiterate. All I know is I have surge protectors as well as some heavy duty cords and have not experienced any issues with my Flex 3401 or PC

I hope that will work and if not I will be at a loss to give you any more help...sorry.

[mcate]

I had a very similar sounding problem with my 1 yr old 7424XP. I called Porter Cable & they gave me the location of a local repair shop. I took it to them & they replaced the motor, free of charge.

[1fastTbird]

Thanks for all of the suggestion from everyone. I finally took mine to the repair show and I am waiting to hear back and what they tell me.

I confirmed that my heavy duty extension cord does meet the requirements from PC. I tried using the unit again yesterday and it started knocking and puked grease all over the backing plate and hood of the car I was polishing.

[DaveT435]

With any manufactured product there is going to be a percentage of bad products. With PC it's pretty low from what I have read. Hopefully it's covered under warranty.

[jfelbab]

You are not missing the spacer washer on the backing plate by chance?

[Kengo123]

Pick up a harbor freight DA in the meantime for a backup!

[sunday joe]

Thanks for all of the suggestion from everyone. I finally took mine to the repair show and I am waiting to hear back and what they tell me.

I confirmed that my heavy duty extension cord does meet the requirements from PC. I tried using the unit again yesterday and it started knocking and puked grease all over the backing plate and hood of the car I was polishing.


Let us know how the repair turned out. All things mechanical eventually break down. Some sooner than later. Is it covered under warranty ?

[mcleod52]

I would take it apart and maybe regrease it

[Mike Phillips]

Just a thought...


When you don't have the compression washer in place the tool sounds like it has rocks growling around inside of it because the rivets on the backing plate rub against the counterweight.


Here's one article I have on this topic with great pictures to show you what happens without the compression washer.


Don't use your polisher without it! (http://www.autogeekonline.net/forum/hot-topics-frequently-asked-questions/48872-don-t-use-your-polisher-without.html)


http://www.autogeekonline.net/gallery/data/1423/5inchbackingpatesonDAPs013.jpg



Just to note... it's real easy for the compression washer to fall off when attaching the backing plate to the tool. Since the PC doesn't come with a backing plate often times the compression washer will fall off when the new use attaches the backing plate for the first time.


To the OP: Remove the backing plate using the PC wrench and check to see if you have the compression washer in place.



:)

[Mike Phillips]

Here's two more related articles....

The Compression Washer (http://www.autogeekonline.net/forum/hot-topics-frequently-asked-questions/48913-compression-washer.html)


The common Compression Washer used with popular DA Polishers is about the size of a U.S. Quarter.

http://www.autogeekonline.net/gallery/data/1423/CompressionWasher001.jpg







Tip: Rubber Nut to protect threads and safeguard compression washer (http://www.autogeekonline.net/forum/tricks-tips-techniques/48922-tip-use-rubber-nut-protect-threads-prevent-loss-compression-washer.html)

http://www.autogeekonline.net/gallery/data/1423/RubberNut01.jpg



And they do wear out....

http://www.autogeekonline.net/gallery/data/1423/CompressionWasher008.jpg



Autogeek carries replacements...

Lake Country Compression Washers 5-Pack (http://www.autogeek.net/backing-plate-compression-washer.html)



:xyxthumbs:

[1fastTbird]

Thanks again for the comments and the assistance from the forum. Everyone has always been a huge help and I do appreciate the community.

I have always used the proper compression washers on the backing plate and confirmed that a nearly new washer was installed during the recent use.

I just got a call from the repair facility and they said that the gears are worn out and that it would be considered and "out of warranty" repair for $85. I told them forget it.

Tools do wear out prematurely and sometimes as a consumer you might be in the minority. It appears that I am in this case as a majority of people have successfully used their machines for years. At the end of the day, even with 10 corrections under my belt, it comes to about $12 per use which is still substantially less expensive than paying someone else to do the work, so I am :coolgleam:


Now I have a conundrum: as a guy just trying to keep his family's cars looking good, is a replacement 7424XP sufficient or do I go big and purchase Flex?

[VISITOR]

Now I have a conundrum: as a guy just trying to keep his family's cars looking good, is a replacement 7424XP sufficient or do I go big and purchase Flex?

IMO every detailer/enthusiast should have at least one traditional PC-style DA and with that said I would recommend the GG6 (this will suit the bill perfectly if you're just keeping the families cars looking good). lots of power/torque, great warranty, and excellent customer service...

Griots Garage 6 Inch Random Orbital Polisher (http://www.autogeek.net/new-griots-polisher.html)
http://ep.yimg.com/ca/I/autogeek_2269_27859469