# [SOLVED] Condenser fails



## throoper (Oct 20, 2006)

Hi all,
I'm hoping someone can give me a clue to this.
I have a 3HP Briggs, Horizontal shaft. It's on a Rotary tiller so only gets used a couple times a year. 
Whenever trying to start it after sitting for a month or more, there's no spark. Points and plug are good, but the condenser is gone. Replacing it solves the problem and it will fire right up. I can start it a week or so later with no problem.
Does anyone know of a reason why the condenser will fail from just sitting?


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## Basementgeek (Feb 7, 2005)

*Re: Condenser fails*

Hi:

What a pain that must be. 

Has it always been like this, replacing after a couple of months setting ?
Like since it has been new.

Are you sure that you are getting the correct one?

Maybe your supplier has got bad ones or really old ones. However I have 
20- 30 year old stuff still running with the original ones.

BG


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## throoper (Oct 20, 2006)

*Re: Condenser fails*

Yes it is a pain.
It hasn't always done it. The machine is about 40 years old and mostly original parts.
It's done it for the last couple years. It's weird because it may go all summer without a problem, if I'm using it every couple weeks. 
It's guaranteed to be bad in the spring. I always touch up the points and plug before starting it for the first time in case a little corrosion set in during storage, but the condenser will not work and has to be replaced. I've used condensers from tune-up kits and also individual parts from different manufacturers from different sources with the same thing happening, so I've ruled out a bad batch of parts. 
Just plain weird.
T.


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## MrChooks (Apr 19, 2008)

*Re: Condenser fails*

:wave: Is it the condenser that is failing or is it just the ground connection between the condenser case that is getting some surface corrosion / gunk that is stopping the thing from working??.

If you take off one of your "sick" condensers - then reinstall it - does it work then?? or are the "sick" condensers really dead??

I only ask as I had a vile old Villiers engine years ago - and the condenser was a shocker for developing a bad circuit to ground - and after a while - it had to be removed and reinstalled to get it to work?? - all in all a total PiA:upset:


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## k2skier (Sep 30, 2008)

*Re: Condenser fails*

In 28 years of repairing engines I've seen 2 bad condensers. The old B&S should have half the points contact on one end of the condenser and the other point half on an arm by itself; is this how your points are? I think you'd have to get back in the 50's (early 60's?) to see B&S points and condensers separately. All you need to test a condenser is a VOA meter and if they're not shorted to ground (pig tail to casing) they're fine, in fact you don't even need the condenser in the circuit to test for spark, they're only there to make the points last longer.

Are you cleaning the points with rubbing alcohol or ether when your done polishing them with fine sandpiper?

Add; in fact if it has a two leg armature on it you may be able to add a Briggs Magnetron (electronic ignition) coil to it and eliminate the pints.


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## MrChooks (Apr 19, 2008)

*Re: Condenser fails*

:wave: agree with k2skier and am at a loss as what could be causing this issue - whilst I haven't been fixing "lill engines" that long - I have never had a condenser actually fail - only those endless poor connection problems with that "vile old Villiers" (which has long since gone to recycling)

As a fall back idea & if the problem persists - can you change the ignition system to solid state version - some older engines were amenable to this and the change over kits weren't that expensive?? If you have a good mower shop nearby - they can often help with what exchange units might be available and fit without too much drama


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## throoper (Oct 20, 2006)

*Re: Condenser fails*

Sorry about the delay responding.

k2skier: It's old. The condenser is one half the point set. I've always carded the points after touching them up and never had a problem. Replacing the condenser instantly solves the problem.

MrChooks: I got lucky and found some of the "sick" condensers. The casings look almost new with no visible corrosion. I know I slid at least two of them down in the housing when checking the point surfaces and thought that would ensure a connection when they were moved back to the proper position. 
Now that I think of it, the housing does develop a dusty film, when touched it leaves a chalky like residue on your finger. I plan on polishing up the housing and trying each of the "bad" condensers. I'll post back with my results in a few days. The weather has taken a nasty turn, so I need to put off the tiller and work on the snowblower.


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## k2skier (Sep 30, 2008)

*Re: Condenser fails*

Please post the model, type and code, you might be able to put a Magnetron coil on it.


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## MrChooks (Apr 19, 2008)

*Re: Condenser fails*

:wave:agree with k2skier - the pointless ignitions are such a huge improvement - so if it were my engine, I would be going down that route. 

I think K2skier has access to B&S parts books for lots of old engines - so if you can give him the engine details and your engine is suitable (even if very old) - then changing out the old ignition for a Magnetron ignition, or something similar would be my recommended route also.


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## throoper (Oct 20, 2006)

*Re: Condenser fails*

Finally got a chance to check this out.
I had 5 condensers I've replaced and saved and cleaned each with emery cloth and solvent to be sure I'd get a good contact. There was an almost invisible film on them.
I did the same with the engine case where they mount. Made sure that "powder coating" was gone and everything was shiny.
3 out of the 5 worked. The 2 that didn't have the same codes stamped on them and look like they might be from the same lot from the same place, so I think that could just be a "Bad batch". :4-dontkno

While it looks like I should have been getting contact, the powdery film must have been preventing it. Even sliding the condenser around wasn't enough to ensure contact.
I've put an auxilliary ground strap on it to the engine block in hopes of maintaining a good contact to ground. 
I guess I'll find out in the spring if it works. At least I won't have to buy a new condenser. :grin:

Many thanks for all the advice and getting me pointed in the right direction.


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## MrChooks (Apr 19, 2008)

:wave: congratulations & well done throoper!!

Looks like your 3HP Briggs had a dose of my old "_vile little Villiers_".

In that stinking engine - it took me years to figure out that it was the condenser connection that was at fault :upset::upset::upset:

The magneto was inside the flywheel - so it was always drama to get to it. I spent ages continually maintaining the points and yet as soon as that _"lill heap of junk_" got hot - it would start misbehaving - finally I bit the bullet - took it all apart and found the condenser culprit.

A final footnote on that "_vile lill Villiers_" - I ultimately did what k2skier suggested - I tossed the OEM ignition and replaced it with an electronic version - and that stopped the problem completely. So if you start having repeat issues with the B&S ignition and if you think the engine is worth saving - I would see if I could get an electronic ignition for it - it eliminates points and condensers!! :grin:


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## SABL (Jul 4, 2008)

Question:

Would it have any impact to apply a thin film of dielectric grease on the area the condensor makes contact with?


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## MrChooks (Apr 19, 2008)

:wave: Good idea - any of the conductive / electrical lube products should be OK to prevent the film building up


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