Engine Stalling


Old 05-16-03, 11:48 AM
hal k's Avatar
Thread Starter
Join Date: Jan 2003
Location: TX
Posts: 42
engine dying under load

I've inherited a 1990's model Mastercraft tiller with a B&S 5HP engine. Tiller is rear tine, a bulky thing.
I can start the thing right up but I have to keep the choke 3/4 engaged to stay running. I took the gas tank/carb off and flushed them out, using carb cleaner on the siphon needles and any jets. There was definitely varnish in the tank but I think I managed to get rid of it all.
I put everything back together and it started right up, idles better but still dies or idles low when I engage the tinesand start tilling. I can manually move the governor and the engine will rev immediately. I'm sure this thing worked well at one time so I'm not sure anything on the governor needs adjusting. I sprayed around the carb checking for air leaks but found none.
Any suggestions?
Sponsored Links
Old 05-16-03, 10:42 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,817
Hello Hal!

Sounds like the spring may have come off the governor linkage, down between the tank bracket and block.
Old 05-17-03, 07:26 AM
Sharp Advice's Avatar
Admin Emeritus
Join Date: Feb 1998
Location: The Shake and Bake State USA
Posts: 10,440
Lightbulb Additional Possible Problems & Solutions

Hello: Hal

There is a possibility the float is not adjusted correctly. The fuel level in the bowl, if not adjusted to the correct level can cause the problem you are describing.

Remove the bowl from the carb. Insure the float is perfectly level when in the closed position. Be sure the fuel flow holes {ports} in the body of the carb and those in the bowl screw, if any, are clean.

Check for fuel flow from the tank. There may not be a steady and or full volume flow of fuel into the carb. Remove the fuel line hose at the carb and allow fuel to flow out for about 1/2 to 1 minute.

The flow rate and volume must remain constant. If there is any slow down in the rate during this time, remove the fuel tanks cap and note any difference.

If the flow rate continues to remain slow or stops, there is a restriction in the tank, fuel line or the vent hole in the fuel cap is plugged and or restricted. Removal of the cap will allow full flow to return to full flow.

Check the fuel filter, if there is one. This filter may be inside the tank or inline in the fuel hose. Check for a fuel shut off valve, if there is one. This part may be slightly restricted.

Read the already asked questions and the replies offered in them on this same type of problem for additional help & information on engine running problems. Doing so will provide additional possible causes and the solutions to correct them.

If you need further assistance, use the REPLY button. Using the reply button moves the topic back up to the top of the daily topic list automatically.

Regards & Good Luck. Tom_B. Web Site Host & Small Engine Forum Moderator. "Accurate Power Equipment Company"
Small Engine Diagnostics Services and Repair.
Old 05-18-03, 12:34 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,817
Just to clarify, don't panic if you can't find a bowl....your engine doesn't have one, (not your conventional one anyway) or fuel lines, from what I can determine by your description of work performed (you mentioned siphon tubes, which indicates that you have a vacu-jet carb mounted to the tank).

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes