Onan twin Condenser

Arti

Arti

Tractorologist
Member
Problem with a 16 hp Onan twin.
Condenser puffed up and the engine started to misfire. I replaced the points , condenser , coil and plug wires.
Mowed the yard and and was very happy with the now good running tractor. The next week I went to mow yard and the same thing happened started it up and after a few seconds it started to misfire so I put a new condenser in it good running motor again.

Yesterday same thing this is the 3rd condenser and I'm not sure what is the cause, I checked charging voltage and it was at 13.9 ?? Any one else have this happen.
 
Replaced the condenser that fit under the point cover and the last one I attached to the cooling shroud next to the coil. I checked with a small motor repair shop and got a Hmmmmmmm.
 
Never ever had a condenser do that, so I'm at a loss as to the problem. Were they all OE condensers? Wrong type would likely do that.
 
Model A fords had a problem with condensers burning out because distributor was next to Manifold . If heat is burning out your condenser. I would remove engine air shields and check your cooling fins are not plugged and making your engine running hot. wrong ignition timing will also make run hot. Get a shop manual for your model and read about wiring and timing. For an Model A ford owners Snyder Antique Auto Parts sells
a short -proof-condenser that last longer.
thanks Bill
 
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Arti said:
Replaced the condenser that fit under the point cover and the last one I attached to the cooling shroud next to the coil. I checked with a small motor repair shop and got a Hmmmmmmm.
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I'm thinking its a heat related problem and there no reason mounting on the shroud won't work as long as its grounded good by the way all the Kohler K series engine have the condenser mount on the engine cooling tin next to the coil
 
On my Case 446, 16 hp Onan, the condenser is under the points cover. seems to work ok. If the engine is running hotter than normal, you would notice that. I did on my Kohler that was running hot. Bonnet and every thing around the engine was to hot to touch. My trouble was the timing was late, but other things can cause over heating too. But if it was the heat causing the condenser trouble, you would notice the engine and surrounding parts hotter than normal, I would think.

What about to much voltage to the points causing the trouble. When engines with points are on the start cycle, the points are fed 12 volts on start up, then when in the run position the voltage is reduced or the coil reduces it. If voltage not reduced, would that cause the condenser to bulge. ?

Noel
 
I'm tending to agree with propane that this is an overvoltage problem. Maybe there's a resistor or resistor wire that is haywire. Maybe a check with the shop manual and/or wiring schematic is needed.
 
I don't agree with a voltage problem I still say heat or a bad ground

Are ignition condensers voltage specific? No such thing as a 6V or 12V ignition condenser. Irrespective of applied primary voltage (6V, 12V, 24V) the condensers are made to withstand the flyback or reverse EMF voltage made by the coil as it's magnetic field collapses when the points open.Mar 1, 2021
 
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He has not said if motor was over heating. So hard to say.

I’m sticking with bad ground. And yes three condensers were put on and you would think one of them would be grounded, but, maybe the engine has a bad ground to frame. ?

And I still on my second guess. Voltage trouble.

If he says engine is hot. Then maybe that’s it.

Noel
 
Here is a note from Krik engines he sells the transdenser that replaces the condenser gives you a Hy-bred electronic ignition system, I have not used his transdenser but have 2 of my Power Kings with K series Kohler fitted with his early version called a Points Saver they work great well worth the money.
From his information " For Onan engine applications, the Trandenser must be mounted externally from the original condenser location (points box) due to thermal reasons. This will require the Trandenser II Mounting Clamp as listed below. "

Kirk Engines >> Garden Tractor Performance Parts

Specializes in garden tractor performance parts for Kohler engines and garden tractor pulling including Cub Cadets, John Deeres and more
www.kirkengines.com
From my exerience with Onans they don't have to be overheating to cause ignition heat problems its the location of the componets that is the heat problem
 
Maybe add wire to the condenser wire and mount it out by the cooling air intake. I never thought about condensers not being voltage sensitive it was just a shot in the dark. With no path to ground how does voltage pass thru it?? And if it can't what effect would that have??
 
It's on a 1980's Case 446 BM twin Onan, Points and condenser under the points cover. However when I replaced it the last time I moved the condenser to the cooling tin cover (Chevy condenser). I'm into this for over $60 for condensers.
I have looked at the Kirk kits however would like to find the problem out before going to electronic ignition, wouldn't want to destroy the electronic ignition .
The bad Ground to Frame is something that I have overlooked, Will check that out soon also the voltage rectifier is mounted behind the dash so perhaps a bad ground there.
Condensers / Capacitors do have a mfd rating as well as a voltage rating. I don't know the volt rating for an automotive Condenser however the one's that I used on Refrigeration units were rated at 440 Volts. At that point the insulation would break down and they would explode. Sitting outside in the winter was hard on Refigeration capacitors because they absorbed moisture which would cause an internal short.

About the location of the points/condenser, I wasn't aware that this engine had them I thought that it was electronic So it's been starting and running for the last 15 years without me servicing them ......
 
Up date on the points/condenser issue

Lawn needed mowed today it's been rainy here and today things were dry enough to mow.
Got the Case out and moved it over to the shop, A quick look and I noticed that the bolts holding the motor to the frame were loose, The ground from the battery goes directly to the motor so if the motor moved around it would lose the ground to the frame. The charging regulator is mounted to a plate under the steering wheel so I suspect that it wasn't grounded at times. Hopefully tightening will fix the problem also it runs without so much noise now that the motor is bolted down tightly.
Keeping my fingers crossed as this problem is getting pricey.
 
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