Change the air filter & plug?

Take the Ninja blade off... The blade being dull, on backwards or too aggressive could just be proving too much for the little engine. Briggs compression #s are top secret and are not published- for several reasons infact. Is this thing old enough to have points? What are the first 2 digits of the code #?

It looks like he has provided the code , not the model number. If so, it will have Magnetron ignition.
It should run with the OEM blade. Maybe the rpm is set too low.

Roadbike, both plug and filter are new.

Tomplum, it's an 89, with magnetron. Has the standard Snapper blade; installed correctly and reasonably sharp

Canguy, the RPM is not fixed; it's controlled with the throttle on the handle. And; the governor seems to be working. I am running it on "FAST".

I've had other Snapper mowers with the same engine (although all my others have had the under the carb gas tank). I've never had one that was so anemic. I'm wondering if the float-bowl carb is jetted wrong; or in some other manner managing to create a lean condition?

More help anyone? I greatly appreciate your time.

Chuck

The throttle may be on FAST but that does not mean the engine is running at the proper speed. The governor spring may be stretched, the linkage bent etc. An overly lean condition wold lead to hard starting and uncontrolled surging.Can you post the rest of the engine numbers?

Thanks canguy....

90702 3080 01 89012703

The throttle control allows the engine to rev up normally. And; the governor linkage (it's the air-vane type) seems fine as well.

I'll watch for your reply....Thanks!

Chuck

Have you had the shroud off yet? I've seen more that one of these that had so much debris inside that had kept the governor blade from doing it's job. While you are there, watch over the intake tube to ensure it is secure. Choke plate fully opens?

tomplum....all your points are well taken; I have re-checked all those areas after reading your post. No issues that I can see.

None of you have commented on the compression. 70 PSI cold should be within range?

Were these engines carbureted differently to compensate for altitude in which they were originally sold? Can it be that it is carbureted lean for a high altitude location?

Thanks guys,

Chuck

For years Briggs said that if you could spin the blade backwards by hand and it would kick back, it had compression to run. (spark plug wire off- recoil sometimes off etc) Obviously your engine runs. If it were a lean issue, one would think you could fudge the choke on a tad to see if that helps matters. Beyond that, do a ring test, pop the head, have a look at valve seats and guide wear, clean it up, put on a more modern coil if you have a donor, check flywheel key. All I can think of at the moment besides spinkling some magic powder on it and dance around it...

I have avoided giving an opinion on the compression reading because it is not an accurate assessment of the engines condition. There is a compression release that eases the starting effort but does not come into play during running. Also, because of the wide tolerances in air cooled engines, the readings would be quite different if taken hot vs cold. A leak down test would be more accurate and give an indication of the source of a compression issue.