Filter capacitor issue


I've been a member for over 10 years and have never posted anything on here so please bear with me. My main system is a Bedini BA-802 solid state amplifier, Music Hall Maverick SACD player, Magnepan MG2.6r speakers, Denon DP-59L turntable with Micro Acoustics MA-2002e cart but I have an issue with a Marantz 2220b receiver that hopefully someone on here can help me with. I bought the receiver with plans to do some simple upgrades ie: replace some caps, etc. and resell it. I When I changed out the large filter caps I inadvertently installed the cap for the left channel backwards. I put both negative terminals on the buss bar. The right channel cap is installed with negative on the buss bar and the left channel cap should have been installed with the positive terminal on the buss bar. Needless to say the left channel cap got angry and blew it's top. After realizing my error I put in a new cap correctly but now the main 2 amp fuse is blowing after about 20 seconds. I'm thinking I may have damaged the power transistors or smaller transistors on the main amp board. The service manual also says to check the thermistors on the amp board. I'm not an electronics tech but my brother is and has been teaching me some basics over the last few months. Unfortunately he's not here to help me out this week so if anyone has any insight into this it would be much appreciated. Thanks in advance, Eddie D.
128x128skymunky57
@skymunky57

Despite how it was delivered, I would heed the advice of some you see here.
On something like this, where the final product isn't going to be worth all that much anyway, you can really get in over your head quite quickly due to its complexity!
If the power rectifier was damaged, the repair might be fairly simple- just replace the rectifier. If the output section was damaged because one rail was shorted by the backwards capacitor, then at that point you have to consider whether the unit is worth repair! That is because its very likely both channels are damaged, and output transistors and their driver transistors that actually work (and aren't counterfeit, which is very common these days) can be rare and expensive since they are likely long out of production.

You will want to have identified all the damaged semiconductors before ordering any of them. In addition, a helpful tool is something called a variac, which allows you to start the AC power from zero volts and slowly raise it until you get to full 117V. Such a unit should have an ammeter, so you can see that you are drawing too much current before something is damaged.

I would at the very least wait until your brother is about.
I'm with kosst_amojan. It's impossible to know what is wrong without a systematic trouble shooting strategy. There could likely be multiple problems that must be addressed before the unit is powered up again. I've made that mistake in the distant past as a newby, so don't feel too bad. Regardless of what others have said, if you like the unit, go ahead and repair it.
I've never seen mention of buss bar in solid state circuit design, only in reference to service panels which go on the outsides of homes.  But to your query, I hope you can create a safe working environment for yourself before doing any more work.  Also, if you love electronics, there are plenty of technical schools and colleges that can provide safe environments for building smaller versions of the things that add up to what you are working on now, over 2, 3 or 4 courses.  Some of the helpful suggestions above are probably well-intended but I would take the capacitor's 'discharge' as a heavenly sign and probably junk or store your science project until help arrives.  You can easily die if the testing method is "hoping it doesn't blow up when plugged in" and you didn't mention if you were working with any isolated power supply, GFCI if you were wearing eyewear, or were near other people when doing this.  Any other attempt for knowledge transfer couldn't cover the one or two-hundred pages of information you will need to protect yourself and the potential buyer, especially the potential cost if a buyer gets hurt.  "Recapping" is probably the worst point to start learning especially if you are not familiar with an overall circuit design, self-preservation, (i.e. no channels at this point) and what each piece does and what specifications to "recap" with.
There's a Marantz 2220b, in good working order, currently on Ebay for $300 (BIN $400)
 https://www.ebay.com/itm/173698186290
You may want to consider it for parts or replacement