Briggs surging heavily

[StarTech]

33R877-0034-G1 DC191023ZD
JD E110

Well it was surging. Currently disassembled awaiting parts.

History that I know of:

• Starter Bendix shattered
• ACR failure
• At been in at least three shops before mine. And one was a JD shop.
• Valve clearance were IN .020" plus EX well over .050. I stop measuring after .050 gauge went through.
• Replaced starter Bendix, Camshaft, and adjusted the valves.
• Was running fine when it was loaded to go home.
• It started surging before the customer unload it so it came back to my shop.

Now the problem was not fuel or mechanical issues so what do you think was happening to cause the surging? The source of the problem had caused over $180 in damages. All because someone didn't keep track of things.

 

[GearHead36]

Not fuel... not mechanical... That leaves electrical. Loose battery terminal or cable?

 

[StarTech]

All electrical connections tight. Just be aware it was doing this at full throttle. All the current damage was cause initially by a less than $5 part.

 

[Hammermechanicman]

Oil starved?

 

[Scrubcadet10]

Anti Afterfire valve problem?
i had one a few weeks ago that surge at full throttle and almost die, the AA solenoid was stuck in the up position.

 

[Tiger Small Engine]

33R877-0034-G1 DC191023ZD
JD E110

Well it was surging. Currently disassembled awaiting parts.

History that I know of:

• Starter Bendix shattered
• ACR failure
• At been in at least three shops before mine. And one was a JD shop.
• Valve clearance were IN .020" plus EX well over .050. I stop measuring after .050 gauge went through.
• Replaced starter Bendix, Camshaft, and adjusted the valves.
• Was running fine when it was loaded to go home.
• It started surging before the customer unload it so it came back to my shop.

Now the problem was not fuel or mechanical issues so what do you think was happening to cause the surging? The source of the problem had caused over $180 in damages. All because someone didn't keep track of things.

If it is hunting and surging, then it is running lean on fuel, as you know. Can only be one of three reasons: 1) air leak intake
2) dirty carburetor 3) governor (long shot).

 

[StarTech]

Oil starved?

Nope, Correct amount of SAE15W50-SYN installed after camshaft replacement.

Anti Afterfire valve problem?
i had one a few weeks ago that surge at full throttle and almost die, the AA solenoid was stuck in the up position.

Anti-after fire solenoid fine.

If it is hunting and surging, then it is running lean on fuel, as you know. Can only be one of three reasons: 1) air leak intake
2) dirty carburetor 3) governor (long shot).

Not either one of these either. So it can be something rarely seen. And it had to happen to me. I only seen it once before over 15 yrs ago.

As I said it was not either mechanical or fuel related and it was the result of someone not keeping track of parts while working the engine. This should not be problem if the techs just keep track of parts as they work on engines. It is my fault for assuming that the simple part that cause all the damage was simply left off and one the reason I hate going in behind another that has worked on a piece of equipment. Just so much of this leaving parts off or rigging up something.

Let me give you a hint. The engine was braking at full throttle and then braking would stop as the engine approach idle speed, it was in a cycle of going to full throttle then braking to idle speed and not braking.

 

[hlw49]

Anti Surge spring

 

[StarTech]

Anti Surge spring

If you are referring to slack prevention spring on the throttle linkage it is not the problem. That is a mechanical problem so that was already eliminated.

 

[Rivets]

How about a bad spark plug wire or connection, opening as rpm’s increase. Or spark plug itself.