Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Vintage Mercedes Forum

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-31-2018, 11:14 AM
twinockchef's Avatar
Registered User
 
Join Date: Jun 2007
Location: Savoy, Texas
Posts: 353
Testing a Solenoid

How is a stater solenoid tested? I want to find out if the solenoid is good or on the edge of failing.
__________________
Britton McIntyre

68 280 SE coupe 'Hairball'
70 280 SL
71 280 SEL - RIP May 2010
Reply With Quote
  #2  
Old 08-31-2018, 11:43 AM
Registered User
 
Join Date: Jan 2006
Location: Tucson, AZ
Posts: 4,501
The only safe way to test is is to remove it from the engine. The starter will "kick" when it is engaged so either mount it in a vise or secure it in some fashion. Connect a 12 volt positive lead to the starter positive terminal and a grounding strap to the body of the starter. Use a 12 volt jumper wire an touch it to the small terminal on the solenoid. You might have two small terminals on the solenoid so if one doesn't engage the starter try the other.

Don't know why you'd go through all the trouble to test it when it's less labor time to simply replace it.

Generally the Bosch solenoids work until they fail. Sneaky SOB's rarely give any warning.
__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now
Reply With Quote
  #3  
Old 08-31-2018, 03:29 PM
Registered User
 
Join Date: Mar 2009
Location: San Diego
Posts: 2,934
Expert with starter or solenoid.

See #15.
__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

2 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.
Reply With Quote
  #4  
Old 08-31-2018, 05:57 PM
Registered User
 
Join Date: Jan 2012
Posts: 7,179
Be aware that if the starter brushes are failing, the solenoid will not pull in. This is because the pull in coil is " grounded " through the starter motor. The hold in winding is grounded to the case however.

Are you having some sort of improper operation? If so, what are the symptoms?
Reply With Quote
  #5  
Old 08-31-2018, 07:03 PM
Registered User
 
Join Date: Jan 2006
Location: Tucson, AZ
Posts: 4,501
There ya go! More info than you'd expected. The members of this forum are sure a handy bunch to know.
__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now
Reply With Quote
  #6  
Old 08-31-2018, 08:03 PM
twinockchef's Avatar
Registered User
 
Join Date: Jun 2007
Location: Savoy, Texas
Posts: 353
The funny thing is that no one has yet to answer the question. How was Bosch able to bench test their solenoids? I would like to determine if the solenoid on my starter needs to be replaced or not.
__________________
Britton McIntyre

68 280 SE coupe 'Hairball'
70 280 SL
71 280 SEL - RIP May 2010
Reply With Quote
  #7  
Old 08-31-2018, 08:29 PM
Registered User
 
Join Date: Mar 2009
Location: San Diego
Posts: 2,934
Quote:
Originally Posted by twinockchef View Post
The funny thing is that no one has yet to answer the question. How was Bosch able to bench test their solenoids? I would like to determine if the solenoid on my starter needs to be replaced or not.
It is not funny at all. Remove the solenoid and Post #3 will show you EXACTLY how to bench test the solenoid. It is a double solenoid with a pull and hold solenoid in there. No one is going to hold your hands here.
__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

2 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.
Reply With Quote
  #8  
Old 08-31-2018, 09:13 PM
twinockchef's Avatar
Registered User
 
Join Date: Jun 2007
Location: Savoy, Texas
Posts: 353
What are the exact perimeters that Bosch uses to determine if a solenoid passes quality standards at the time of of manufacture and do not tell me that the pass or fail standards at Bosch are that it turns on or does not. I am looking for very exact information.
I had already bench tested the motor and the solenoid before asking this question. I know that everything works. I want to how long it will last. I want to know how to determine the life span of the solenoid. Not just that it works or not.
Oh and by the way I do not need my hands held. Thank you very much.
__________________
Britton McIntyre

68 280 SE coupe 'Hairball'
70 280 SL
71 280 SEL - RIP May 2010
Reply With Quote
  #9  
Old 08-31-2018, 11:56 PM
Registered User
 
Join Date: Jan 2012
Posts: 7,179
Quote:
Originally Posted by twinockchef View Post
What are the exact perimeters that Bosch uses to determine if a solenoid passes quality standards at the time of of manufacture and do not tell me that the pass or fail standards at Bosch are that it turns on or does not.
You could contact Bosch however, I doubt they would give this info out ( or even have it handy. ) .

It is very likely the Bosch manufacturing test for most of this coming off the line is " works or not ", with a few pulled for more extensive testing.

Quote:
Originally Posted by twinockchef View Post
I am looking for very exact information.
Do you have a sense of what characteristics you are looking for?

Quote:
Originally Posted by twinockchef View Post
I had already bench tested the motor and the solenoid before asking this question.
What quantitative tests have you performed on the starter motor? This would give me some sense of what test equipment you have and how it can be applied to the solenoid testing.

Quote:
Originally Posted by twinockchef View Post
I know that everything works. I want to how long it will last. I want to know how to determine the life span of the solenoid. Not just that it works or not.
It is very difficult to determine how much longer your specific solenoid will last unless you have records of number of crank cycles , length of each crank cycle and amperage draw for the solenoid coil and starter motor . You will also need statistical data from other failures to determine MTBF and where on the curve your solenoid lies.

Quote:
Originally Posted by twinockchef View Post
Oh and by the way I do not need my hands held. Thank you very much.
. . I hold the truths to be self evident. . .
Reply With Quote
  #10  
Old 09-01-2018, 08:46 AM
ejboyd5's Avatar
Registered User
 
Join Date: Aug 2004
Location: Southold, NY
Posts: 255
Quote:
Originally Posted by twinockchef View Post
I know that everything works. I want to how long it will last. I want to know how to determine the life span of the solenoid. Not just that it works or not. Oh and by the way I do not need my hands held. .
You are asking a question for which there is no absolute answer. If you are half as experienced as you make yourself out to be, you already know that manufacturers spend untold amounts of time and money trying to determine the expected lives of their products in various environments and uses. Regardless of the results of this testing and the average values obtained, many units last far longer than would be expected and some fail after very few cycles.

Just as a Magnaflux test will tell you that a part is not presently cracked, it does not tell you that it will not crack tomorrow. There is simply no way to predict how long any individual unit will last. If you are worried about your solenoid, replace it, but there is no guarantee that the replacement part is any better than what you have or that it will last any longer. Actually, given the quality of electrical parts today and the number of failures encountered right out of the box you might be better served by sticking with what you have.
Reply With Quote
  #11  
Old 09-01-2018, 10:06 AM
Diseasel300's Avatar
Registered User
 
Join Date: May 2016
Location: Texas Hill Country
Posts: 4,666
Quote:
Originally Posted by twinockchef View Post
What are the exact perimeters that Bosch uses to determine if a solenoid passes quality standards at the time of of manufacture and do not tell me that the pass or fail standards at Bosch are that it turns on or does not. I am looking for very exact information.
As mentioned above, only Bosch knows what the *Exact* parameters are for a test. Likely winding impedance, winding insulation resistance, and whether or not "it turns on or does not".

Solenoids are pretty simple. They work or they don't. There isn't much else to test.
__________________
'11 Honda Accord EX - "The Daily" 64K
'83 500SL Euro - "The Money Pit" 116K
'91 350SD - "The Diseasel Jr." 168K
'86 300SDL - "The Diseasel" 189K (Totaled 1/31/19)
The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Reply With Quote
  #12  
Old 09-01-2018, 11:15 AM
twinockchef's Avatar
Registered User
 
Join Date: Jun 2007
Location: Savoy, Texas
Posts: 353
Yea thats what I thought the answer would be. Sorry but I made the mistake of not framing the question in better detail. Which brought about a lot of answers which I already knew.
I had already spoken with a starter repair company. They said that it was almost impossible to predict when a solenoid would fail which is what I already suspected.
I am not 100% sure about the this starter. I can tell that it has been rebuilt but the solenoid is probably original. At 50 years old I have doubts about the longevity and performance of it. It is the lack of history with this car that has caused many a problem for me. This being my second full restoration of a 60s era Mercedes. I have learned that it is better to just rebuilt or replaced almost everything.
My goal was to find out if there were a way to measure the performance of the solenoid and find out if it was still within the specifications for optimum performance. I am sure these specifications exist. But is the equipment available to actually measure it and will Bosch supply and the specifications?
I am tempted to purchase a new solenoid and install it on the starter but I do have another starter which I may put into the car. I know the history of this starter as opposed to the one I took out of the car.
And yes I do know a lot about these cars but my Achilles' heel of auto restoration is the electrical systems. I have the damnedest time trying to figure it out or more accurately remembering how everything works electrically.
I think everyone and I appreciate all of your answers.
Take Care
__________________
Britton McIntyre

68 280 SE coupe 'Hairball'
70 280 SL
71 280 SEL - RIP May 2010
Reply With Quote
  #13  
Old 09-01-2018, 11:38 AM
Registered User
 
Join Date: Mar 2009
Location: San Diego
Posts: 2,934
Let me hold your hands one more time.

1) solenoid works or doesn't work. It is only a coil and the MTBF is in the million.
2) there is a big metal contact inside to shunt the 12v to the starter motor. They can be pitted and don't make good contact. Starter/engine motor will not turn as a result.
3) the starter motor winding plus the carbon brushes are in series of the pull solenoid. If they are not in good shape then the solenod will not pulled and shunt the big contact. So no click noise. No starter/engine turn.

Good luck.

Let me make extra comments.

a) If you don't hear the solenoid click ( pull solenoid working ) then it could be the pull solenoid or the starter motor winding/carbon brushes. The winding and the brushes are in SERIES with the pull solenoid. That is why sometimes you hammer on the starter motor and it will work. It is because the carbon brushes is on a dead spot on the winding armature.
b) If you hear a click but no turn then it could be the BIG contact pitted inside the solenoid or the starter motor winding/carbon brushes faulty.
c) Solenoid and start motor are interdependent and is difficult to be 100% sure which one is at fault.
__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

2 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Last edited by ah-kay; 09-01-2018 at 12:17 PM.
Reply With Quote
  #14  
Old 09-01-2018, 11:57 AM
Diseasel300's Avatar
Registered User
 
Join Date: May 2016
Location: Texas Hill Country
Posts: 4,666
If you have ANY reservations about the quality or condition of the solenoid, replace it. It's an inexpensive part, and the time to replace it is when the starter is removed from the vehicle. The solenoid itself very rarely fails, it's usually the switch contacts that fail (hence the clunk, but no start condition). It's impossible to inspect the switch contacts, the course of action is replacement.
__________________
'11 Honda Accord EX - "The Daily" 64K
'83 500SL Euro - "The Money Pit" 116K
'91 350SD - "The Diseasel Jr." 168K
'86 300SDL - "The Diseasel" 189K (Totaled 1/31/19)
The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Reply With Quote
  #15  
Old 09-01-2018, 09:20 PM
Registered User
 
Join Date: Jan 2012
Posts: 7,179
Quote:
Originally Posted by twinockchef View Post
And yes I do know a lot about these cars but my Achilles' heel of auto restoration is the electrical systems. I have the damnedest time trying to figure it out or more accurately remembering how everything works electrically.

Gee, nothing like being clueless about electrical parts then getting belligerent with those that actually know how things work.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 02:00 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page