Recent Topics
In the unlikely event of a crash
by StevieC. 09/21/18 10:09 PM
Craigslist time wasters
by Anduril. 09/21/18 09:41 PM
Who runs a 20wt here?
by StevieC. 09/21/18 07:31 PM
Need help on edit profile
by jetmech1. 09/21/18 06:34 PM
Oil thickness on the dipstick
by Idlewild294. 09/21/18 05:40 PM
Chinese WIX Trans filter bad, let me down..
by jetmech1. 09/21/18 04:47 PM
Gen 8 Accord rear brakes-What tool?
by fdcg27. 09/21/18 04:30 PM
Ammeters?
by buck91. 09/21/18 03:55 PM
Need Help with Double D Knock Out Punch
by user52165. 09/21/18 03:41 PM
Opinion needed....
by Duffyjr. 09/21/18 02:56 PM
2017 nissan sentra
by jahwarrior1423. 09/21/18 02:47 PM
Another dealership service cautionary tale
by Zee09. 09/21/18 02:29 PM
Liqui Moly
by dawgn86. 09/21/18 02:10 PM
Valve issues
by kawie_guy. 09/21/18 01:54 PM
2018 Elantra SE
by wolf_06. 09/21/18 01:36 PM
Nasty looking oil filter
by atikovi. 09/21/18 12:43 PM
Laughing hard.
by StevieC. 09/21/18 12:26 PM
Newest Members
JRMFt11, Navyretired, aikwae, ScottRousell, Direct_Rejection
66036 Registered Users
Who's Online Now
95 registered members (4WD, 14Accent, 77GrandPrix, 87sammy, A310, 9 invisible), 1,355 guests, and 42 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics290,797
Posts4,850,578
Members66,036
Most Online3,590
Jan 24th, 2017
Donate to BITOG
Previous Thread
Next Thread
Print Thread
Hop To
Page 1 of 2 1 2
Electronics savvy, please comment.... #4638465
01/18/18 08:37 AM
01/18/18 08:37 AM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
I have an MSD box, which is an ignition box for a vehicle. This transistor seems to intermittently spark a little around the edge when engine is running. I can see it at night when I block the light around the box. Now, Is this due to that piece not being grounded properly with the screws holding it down tight enough , or would it be something else? It has 2 and only one does this and it does get a little warmer than the other one that doesn't spark. I don't know anything about electronics to troubleshoot. Thanks!! Also, has anyone here ever repaired MSD boxes?


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638517
01/18/18 09:17 AM
01/18/18 09:17 AM
Joined: Jun 2015
Posts: 4,225
New England
Virtus_Probi Offline
Virtus_Probi  Offline
Joined: Jun 2015
Posts: 4,225
New England
Can you see the markings on the problem transistor so we can figure out what node the tab is connected to?
I don't deal an awful lot with discrete power xtors, but I looked a random bipolar family in a TO220 package and the tab was the collector whether the device was a PNP or NPN. The collector is unlikely to be ground for an NPN, but it's quite possible for a PNP. You could also have a FET that might have totally different connections, really would be good to get the part ID if possible.


2014 Forester XT, 86000 miles
Last Change;
M1 5W30 d1G2
Tokyo Roki 15208AA170 filter
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638518
01/18/18 09:17 AM
01/18/18 09:17 AM
Joined: Jul 2014
Posts: 119
North TEXAS
oldoak2000 Offline
oldoak2000  Offline
Joined: Jul 2014
Posts: 119
North TEXAS
Insofar as electronics, Careful, the case of the transistor is 'part' of the circuit, and should not be 'grounded' to anything that it isn't already connected to. Its normal for them to get warm during operation. 'Grounding' it may cause it to short-out and overload, thereby burning it out.

I'm not a 'msd' expert, but it shouldn't be sparking around the transistor; however, the transistor itself only switches LOW voltages (under a hundred volts) - probably energizing/switching (on/off) the 'bat' side of a coil (much like points would on a classic engine). If there is sparking, it's being leaked from somewhere else in the circuit on the HV side, or maybe even bad spark-plug wires or plugs with too much gap (worn).

Re: Electronics savvy, please comment.... [Re: daves66nova] #4638551
01/18/18 09:53 AM
01/18/18 09:53 AM
Joined: May 2009
Posts: 12,192
N.H, U.S.A.
ARCOgraphite Offline
ARCOgraphite  Offline
Joined: May 2009
Posts: 12,192
N.H, U.S.A.
Regular iggy coils resonate so they are "multiple spark" also.

This on a high comp race engine? If not get rid of it.

____________________

If yoyu wish to ftry to fix it:


You make be getting leak back from the high tension side. Check for cracks and bad secondary lead.

Open the unit and look for traces on the boards if its not potted.
OTW most power transistors should have thermal compound or film
under the semiconductor switch. It get dried up. Maybe remove and re compound.

Last edited by ARCOgraphite; 01/18/18 10:05 AM.

2014 Nissan Rogue S CVT, OC#9 41392mi-QSUD10W30 + M110A CHAMP Filter; 2017 Subaru Crosstrek CVT OC#2 ?? mi-SOA/Idemitsu 0w20 + SOA Filter
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638567
01/18/18 10:07 AM
01/18/18 10:07 AM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
I hope this pic downloaded.
Yes it did. The area where it sparks is at the lower left edge of the transistor. The car just a 22R Toyota engine, daily driver.

Last edited by daves66nova; 01/18/18 10:09 AM. Reason: added on

THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638635
01/18/18 11:10 AM
01/18/18 11:10 AM
Joined: Oct 2014
Posts: 11,844
Idaho
CT8 Offline
CT8  Offline
Joined: Oct 2014
Posts: 11,844
Idaho
Contact MSD.


2015 Ford F150 2.7
2018 Ford F350 6.2
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638667
01/18/18 11:55 AM
01/18/18 11:55 AM
Joined: Jun 2015
Posts: 4,225
New England
Virtus_Probi Offline
Virtus_Probi  Offline
Joined: Jun 2015
Posts: 4,225
New England
That is a power PNP and the case is the collector, so it is possible the case is tied to ground.
Is there a screw head sheared off in the upper right or is that just a different type of component holding the case down?
If it's sparking near the screw, I can't see any harm in trying to tighten the screw to see if that helps (keep yourself isolated JIC).


2014 Forester XT, 86000 miles
Last Change;
M1 5W30 d1G2
Tokyo Roki 15208AA170 filter
Re: Electronics savvy, please comment.... [Re: CT8] #4638671
01/18/18 11:57 AM
01/18/18 11:57 AM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
Originally Posted By: CT8
Contact MSD.
Their tech support and online forum is WORTHLESS.


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: Virtus_Probi] #4638676
01/18/18 12:03 PM
01/18/18 12:03 PM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
Originally Posted By: Virtus_Probi
That is a power PNP and the case is the collector, so it is possible the case is tied to ground.
Is there a screw head sheared off in the upper right or is that just a different type of component holding the case down?
Missing screw there. I installed one recently.


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638689
01/18/18 12:16 PM
01/18/18 12:16 PM
Joined: May 2009
Posts: 12,192
N.H, U.S.A.
ARCOgraphite Offline
ARCOgraphite  Offline
Joined: May 2009
Posts: 12,192
N.H, U.S.A.
was the switch previously blind riveted to the case/heatsink? Maybe your screw went too deep and is near a B+ trace underneath.

I'm sorry, overall but Looks like junk from a distance.

I would Remove it, go back to stock, but use IR plugs if single coil ignition.

Last edited by ARCOgraphite; 01/18/18 12:19 PM.

2014 Nissan Rogue S CVT, OC#9 41392mi-QSUD10W30 + M110A CHAMP Filter; 2017 Subaru Crosstrek CVT OC#2 ?? mi-SOA/Idemitsu 0w20 + SOA Filter
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638695
01/18/18 12:19 PM
01/18/18 12:19 PM
Joined: Oct 2011
Posts: 1,376
CA
user52165 Offline
user52165  Offline
Joined: Oct 2011
Posts: 1,376
CA
MSD = May Self Destuct

I've seen so many problems with MSD. How do they even still survive as a business?

What possible reason for this box on this engine??


Last edited by user52165; 01/18/18 12:29 PM.
Re: Electronics savvy, please comment.... [Re: ARCOgraphite] #4638697
01/18/18 12:23 PM
01/18/18 12:23 PM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
Originally Posted By: ARCOgraphite
was the switch previously blind riveted to the case/heatsink? Maybe your screw went too deep and is near a B+ trace underneath.

I'm sorry, overall but Looks like junk from a distance.

I would Remove it, go back to stock, but use IR plugs if single coil ignition.
I believe it previously had screws on each end. Im running the box. Does run better, smoother with it.


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: user52165] #4638722
01/18/18 12:57 PM
01/18/18 12:57 PM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
Originally Posted By: user52165
MSD = May Self Destuct



What possible reason for this box on this engine??

Easier starting hot or cold, smoother running, possible mpg gain, spare box just laying around, easy to install,etc,etc


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: ARCOgraphite] #4638723
01/18/18 12:59 PM
01/18/18 12:59 PM
Joined: Apr 2004
Posts: 3,662
los angeles
daves66nova Offline OP
daves66nova  Offline OP
Joined: Apr 2004
Posts: 3,662
los angeles
Originally Posted By: ARCOgraphite


I'm sorry, overall but Looks like junk from a distance.
It works is what counts, not "looks"


THIS SPACE FOR RENT, PLEASE PM ME.
Re: Electronics savvy, please comment.... [Re: daves66nova] #4638735
01/18/18 01:12 PM
01/18/18 01:12 PM
Joined: Jun 2015
Posts: 4,225
New England
Virtus_Probi Offline
Virtus_Probi  Offline
Joined: Jun 2015
Posts: 4,225
New England
Is it possible that one of the wires crossing over the lower left edge of the xtor is missing insulation on the bottom?


2014 Forester XT, 86000 miles
Last Change;
M1 5W30 d1G2
Tokyo Roki 15208AA170 filter
Page 1 of 2 1 2

BOB IS THE OIL GUY® Powered by UBB.threads™