HF 79 idle issues

foundmydog · Nov 5, 2011

Curious if anyone had this issue, and what the fix was....

Engine will only start and idle at 90% choke or so... anything more or less choke will kill her instantly

Fresh gas in her, emptied the bowl, spark plug looks good...

Any ideas?

Tahq · Nov 6, 2011

Possible carb air leak, have you checked the plug to see if its running lean?

jbcruisin · Nov 6, 2011

One of the tiny passages in the carb might be blocked. Take the carb apart & blow all the holes out with an air hose. This sounds like what happened to me last summer & that's how I fixed it.
Jay

foundmydog · Nov 8, 2011

Took the carb off and dismantled it and cleaned it with carb cleaner spray and air as well... clean out the jet extremely well

Cut out a new gasket for the intake to rule out an air leak also

Pulled the plug which was a little black and threw in a new plug gapped at .027"

Emptied gas tank and refilled with new gas

AND.....

I can get her to idle with the choke off at a high idle only.... if I try and adjust her down to idle she dies right out

I pulled the whole exhaust off and ran it that way to see if I had a clogged exhaust.... but to no avail... trying to lower the idle to normal kills her

When high idling with choke off or half on ( warmed up already ) and goosing it, she hesitates to a stall or bogs down before revving up

Any ideas???

Maybe compression leak or bad head gasket???

Quenton Guenther · Nov 8, 2011

Check the lifter clearance! I checked 3 new motors and all were way off, and all different between them. Also take a close look at the magneto to make sure it is tight, straight and gapped corrctly.

Have fun,

scotto- · Nov 8, 2011

After you try the things Quenton suggested and it is still not idling properly, it may just be a bung carb.....I've seen it before with these symptoms. Good luck, you'll eventually find the cause.

wayne z · Nov 8, 2011

Sounds like you still got a prob with the low speed jet system or miss adjusted idle mix needle.

You said you cleaned the "jet" . Prolly main Jet. It's orfice is huge compared to the idle jet. The idle jet is tiny and clogs so easy.

The carb has 2 circuits, Hi speed and low speed. Usually, the low speed circuit is the hardest one to get sufficently clean by us tinkers :~)

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HF 79 idle issues

foundmydog

New Member

Tahq

New Member

jbcruisin

Active Member

foundmydog

New Member

Quenton Guenther

Dealer

scotto-

Custom 4-Stroke Bike Builder

wayne z

Active Member