Faulty Governor on Qualcast Classic AQ148 Causing Engine Over Speed

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mowerrob
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Faulty Governor on Qualcast Classic AQ148 Causing Engine Over Speed

Good morning,

I'm on a mission to return a Qualcast Classic 43s (35s) to health but the latest fault is causing me to seek external help.

Currently, the engine starts and idles but as soon as any throttle is applied the engine does straight to max rpm.  Checking the governor components externally everything looked good apart from the shaft being loose.  Took the crankcase cover off to investigate further and found the governor gear weights all dented and the spool no-where to be seen.  Later on, I found a single part of the spool laying in the bottom of the sump but 80% AWOL.

The motor now needs a new governor gear, spool and anything else that comes between the governor gear and shaft that passes through to the external world.  Ideally, I would also release the cam gear and oil seal but at this point, the budget is near zero.

Where can I found a list of part numbers for the governor gear and spool and help to identify anything else that's missing?  Engine documentation, parts list or pictures?  I can post my own pictures later to hopefully help someone else to diagnose the same issue faster.

Rob

wristpin
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The AQ148 was essentially a

The AQ148 was essentially a Tecumseh BH35 so this may help

https://www.dropbox.com/s/edfmfx3j5zda456/Tecumseh%20BH35%20Suffolk%20A1...

mowerrob
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Joined: 08/12/2018 - 15:47
Thankyou Wristpin,

Thankyou Wristpin,

The governor parts within mine are different to the BH35.  Reading a bit of Tecumseh documentation, all small frame horizontal engine governor spools were made "retainerless" from 1996+ so could account for the difference.  Pretty sure if it has a circlip holding it in place it would not have escaped and caused so much damage?  Guess it saved Tecumseh 0.5p per engine to remove it.

The more I look, the more parts have been damaged.  The camshaft gear and a lobe are both damaged so without changing the oil seals its likely to be £20+.  Ask myself is it worth it?

Rob

 

AQ148 Governor GearAQ148 Governor internal leverModified AQ148 Governor SpoolAQ148 Governor Spool and Gear reunited

 

mowerrob
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Last seen: 10 months 1 week ago
Joined: 08/12/2018 - 15:47
The closest I can find are

The closest I can find are part numbers are 16170005 and 22740010 for the Gear and Spool.  Fingers cross!

mowerrob
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Last seen: 10 months 1 week ago
Joined: 08/12/2018 - 15:47
One last post as either found

One last post as either found the cause or another victim.  There is a washer that sits on the governor linkage just inside the crankcase.  It should be about m6 15x1.5mm (ish) in size although in my case over time the internal hole has become bigger (about 7.5mm) which allows it to slip over the barbs on the linkage.  It's now free to bounce off the governor gear weights, damaging them and causing the spool to become free.  All caused by a 1p washer failing.

You can see the washer dangling on the linkage in the second picture above and the barbs near the crankcase above.  It should be between the case and barbs.  Off to the shop to by a washer.