old Briggs Stratton very hard to start

Minniemo · Oct 7, 2008

I have an old Briggs & Stratton model ZZ engine. It starts, but is very hard to start. It seems that gas is not getting to plug but the carb is flooding (gas running out). I use another engine to turn it over. Probably, after about 3 minutes of steady turning it started, ran for about 2 minutes and stopped.
I have a lotta fire.
Any ideas what could cause problem?

Karl in MD · Oct 7, 2008

If you look in the spark plug hole, you will see that there is only a small (1/4") hole between the plug chamber and the combustion chamber. If you are careful, you can drill out that hole to about 3/8 or 1/2 inch. That should ease your starting problems. We did it 30 years ago on a ZZ we had on a David Bradley Handiman tractor, and it made a big difference.

Michael Soldan · Oct 7, 2008

Go to Carquest and get a can of "Kleens"...get the engine running and spray into the carb..guaranteed! People used to bring lawn mowers into our shop, if we weren't busy we get 'em running..drain old gas, fresh plug , spray with Kleens and ..a perfect running enhine that didn't come back

JDemaris · Oct 7, 2008

You have to check the basics first - before tying to use "magic" remedies. The ZZ Briggs is a very easy starting engine when it's in decent shape. I've got three large walk-behind tractors with ZZs. All of them usually start 1st or 2nd pull of a rope.

The valves and seats must be tight or it won't draw fuel from the carb properly. That is probably the most important thing to do on any old engine. And, of course the points need to be filed once in awhile - and condensor checked. All very simple basic stuff for a simple engine.

El Toro · Oct 7, 2008

Hold your finger over the plug hole and have someone to crank over the engine and see if you have good compression. You can hold your hand over the throat of the carburetor while cranking it over with another engine to see how much suction you have. You need good manifold vacuum
to suck that fuel into the engine. Low suction could be valves not seating or rings worn or stuck
or a worn cylinder. I use my garden tractor to crank the B&S 23 engine on my Toro mower since it has a lot of compression. Saves my arm. Hal

Anonymous-0 · Oct 7, 2008

its a briggs scrapiron engine, cant expect much more

olgentdc · Oct 7, 2008

USE ONLY PREMIUM GAS FOR THESE JOKERS , and chainsaws , the Modern flea pizzzzgasoline we have today goes sour in 3 weeks and won't fire worth a hoot

Glen D Anderson · Oct 7, 2008

"its a briggs scrapiron engine, cant expect much more"

VERY contributory advice to the problem at hand.........

flying belgian · Oct 7, 2008

We had one. got very hard starting also. Problem was it was just plain wore out. check the compression. I bet it is real week. Ours had almost none. Only way we could get it started was like you. Belt it up to another engine.

Brian Jasper co. Ia · Oct 7, 2008

I'm going to jump in and say check basic mechanical. I have a couple of the old big cast iron Briggs motors. The mechanically healthy ones start easy. Once they're lacking in compression, belting them to another to start is what it takes. At least you have good spark. That old horse shoe looking coil they use is very hard to find these days. If you need to rebuild it, if I remember correctly a model 23 Briggs uses the same connecting rod and piston.
I find many times when I acquire an old engine like these (quit counting after I passed 50 small engines) I find most often a valve job will restore compression. I have had to find very few ignition coils. Points can usually be filed. I prefer to burnish them. From there, clean up the carb. I have quite a few n.o.s. Briggs parts. Pretty sure I have a rod and maybe a set of rings. I know a few other guys that have more parts than me. Email me if you need more help/parts.

old Briggs Stratton very hard to start

Minniemo

New User

Karl in MD

Member

Michael Soldan

Well-known Member

JDemaris

Well-known Member

El Toro

Well-known Member

Anonymous-0

Well-known Member

olgentdc

Well-known Member

Glen D Anderson

Member

flying belgian

Well-known Member

Brian Jasper co. Ia

Well-known Member

Similar threads