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View Full Version : 14.5 Briggs i/c MTD 42" Won't continue to run/idle.


frankrizzo
06-18-2007, 11:24 AM
Hello,

I'm trying to assist a friend. He has an older (7-10 years old) 14.5 Briggs i/c MTD 42" that won't continue to run/idle. It starts with gas/starter fluid, but dies after word very quickly. I took a compression test and it's holding at 90LBS. When it does start, it does not smoke.

We swapped out two different carbs. Cleaning both and soaking them in carb dip for 48 hours. Rebuilt and installed. Again, it will only start with assist from starting fluid or splash of gas.

Now here is the tricky part, on a hunch i shoved a rag in the breathway of the air cleaner. Really restricting the airflow. Much more so that the choke does, but still allowing some air to pass. Bingo It will run like that. Accually runs pretty well too. I can actually get it to almost idle. I checked for vacuum leaks or cracks on the intake (this one is aluminum) and I can't locate any..

Any ideas?

Restrorob
06-18-2007, 01:18 PM
What's the model & type numbers off the engine ?

frankrizzo
06-18-2007, 02:14 PM
Working on getting that info..Should have it a little later today.

When we went through both carbs, I made sure all the jets were removed, and any passageways were clear. I was a little shocked that it ran when i was choking the crap out of it with the rag.

sundiver
06-18-2007, 02:54 PM
model # 287707
Type: 0153-01

Bill Kapaun
06-18-2007, 04:37 PM
Is this a gravity fed fuel system? IF so, are you using the RED filter?

frankrizzo
06-18-2007, 04:47 PM
It is gravity fed, by red filter I'm not sure what you mean. If I recall I've seen a red filer that is rather saucer shaped and is "short" on another tractor. This does not have that kind of filter on it. Seems to be maybe a generic "basic" small filter. I am sure the carb is getting gas though. Every time I remove the anti fire back valve from the bowl, a decent amount of fuel drains out.

frankrizzo
06-18-2007, 05:42 PM
Is this a gravity fed fuel system? IF so, are you using the RED filter?

I seen this filter before:
http://www.northerntool.com/images/product/images/705018_med.gif

But this machine does not have that style. It's more of a clear basic plastic filter
like this:
http://www.hardwarestore.com/media/product/283275_front200.jpg

Bill Kapaun
06-18-2007, 06:58 PM
Go to the Briggs website and download the IPL-
http://www.briggsandstratton.com/display/router.asp?docid=78484

Make sure the main jet is clear. Part 117/118
Is this the Nikki or Walbro carb?

"We swapped out two different carbs"
They list different carbs for gravity feed or fuel pump engines....
If you are using a "pump" carb on a gravity flow engine?????????

frankrizzo
06-18-2007, 07:19 PM
The two carbs were both from gravity fed motors. Both are 14.5. I believe it's a Walbro. Looks similar, not exact but very close to this:

http://www.learnsmallenginerepair.com/1409.gif

Bill Kapaun
06-18-2007, 07:52 PM
That appears to be the Walbro, which I guess is considered more desirable. According to the IPL, Briggs lists Walbro as the replacement for NIKKI.
You still have to clean the main Jet.

frankrizzo
06-18-2007, 09:42 PM
It's the Walbro for sure. 100%.

Almost 100% sure the jets are clear, but I am going to take it back apart to verfy.

Restrorob
06-18-2007, 09:52 PM
While you have it apart make sure the tip of the fuel cut-off solenoid is moving freely and not gummed up, Also plug it back into the harness and watch it while switching the key off and on to make sure it's pulling the tip in all the way.

frankrizzo
06-18-2007, 11:52 PM
Go to the Briggs website and download the IPL-
http://www.briggsandstratton.com/display/router.asp?docid=78484

Make sure the main jet is clear. Part 117/118



I presume the following is one of the jets. Yes it's been removed and cleaned.

http://i184.photobucket.com/albums/x285/frankrizz0/101_2424a.jpg

Is this 117 or 118? Are there two jets? or just one but different types? (by the way this is not the carb in use. But an identical one used as an example)

@ Restrorob


While you have it apart make sure the tip of the fuel cut-off solenoid is moving freely and not gummed up, Also plug it back into the harness and watch it while switching the key off and on to make sure it's pulling the tip in all the way.


A brand new solenoid is in use, because he broke the old one trying to remove it. It moves very freely. I have to test to see if it is indeed being pulled down on switch activation.


Thanks

Bill Kapaun
06-19-2007, 02:44 AM
Sure looks like a Jet to me!
Only one Main Jet used on this engine.