Desmogged 76/FJ40 Idles great, needs 1/4 choke to run well while driving

Joined
Apr 19, 2010
Messages
2
Location
Colorado
76 FJ40 with Rebuilt original carb, fully desmogged. Starts well, Idles great. Drives ok but needs 1/4 choke to run smoothly. I live in Colorado Springs, 7000 ft above sea level. The Cruiser was purchased new in Colorado.
 

thebigredrocker

SILVER Star
Joined
Nov 5, 2013
Messages
3,578
Make sure the fuel cutoff solenoid has power and clicks when key is turned. With rig running, disconnect solenoid power, rig should die.

Pull air cleaner, shine light down primary. If you can seen fuel spray at idle you're not running off the idle fuel circuit. With rig off, use light to confirm secondary butterfly is closed and primary is almost closed. Butterfly open too much will not allow idle fuel to be sucked out properly.

Hook a vacuum gauge to the intake and get a reading at idle. You should see around 18 on a warm engine. If vacuum is low spray carb cleaner around intake and listen for RPM change. Also can pull and plug brake booster hose to eliminate leaky booster as the culprit. Double check all vac hoses and ports are not leaking vacuum. No leaks detected, pull valve cover and adjust valves. Valve adjustment is key. Valve adjustment procedures can be found in FAQ, shop manual or by asking someone to find you that thread. :cheers:
 
Joined
May 25, 2019
Messages
101
Location
Prospect Ky
Make sure the fuel cutoff solenoid has power and clicks when key is turned. With rig running, disconnect solenoid power, rig should die.

Pull air cleaner, shine light down primary. If you can seen fuel spray at idle you're not running off the idle fuel circuit. With rig off, use light to confirm secondary butterfly is closed and primary is almost closed. Butterfly open too much will not allow idle fuel to be sucked out properly.

Hook a vacuum gauge to the intake and get a reading at idle. You should see around 18 on a warm engine. If vacuum is low spray carb cleaner around intake and listen for RPM change. Also can pull and plug brake booster hose to eliminate leaky booster as the culprit. Double check all vac hoses and ports are not leaking vacuum. No leaks detected, pull valve cover and adjust valves. Valve adjustment is key. Valve adjustment procedures can be found in FAQ, shop manual or by asking someone to find you that thread. :cheers:
I have similar problem. I am currently putting new vac lines on all where needed 3mm? I wired my idle solenoid to the coil (+) and grounded other wire on the replacement solenoid I ORDERED from cool cruisers. I have eliminated smog controls as my smog pump was not working anyway. Is the smog control computer needed with this hook up? I have capped all other former vac connections that were not needed. Can't get good low idle, and after heating up and running good, it revs up and down when started hot at idle until I drive it awhile. I will be checking my brake booster because when engine stalls I loose hydraulic braking. (due to vacuum loss?) It is very temporary but dangerous. Thanks for any help you can give me
 
Joined
Nov 18, 2015
Messages
10
Location
Omaha, NE
Make sure the fuel cutoff solenoid has power and clicks when key is turned. With rig running, disconnect solenoid power, rig should die.

Pull air cleaner, shine light down primary. If you can seen fuel spray at idle you're not running off the idle fuel circuit. With rig off, use light to confirm secondary butterfly is closed and primary is almost closed. Butterfly open too much will not allow idle fuel to be sucked out properly.

Hook a vacuum gauge to the intake and get a reading at idle. You should see around 18 on a warm engine. If vacuum is low spray carb cleaner around intake and listen for RPM change. Also can pull and plug brake booster hose to eliminate leaky booster as the culprit. Double check all vac hoses and ports are not leaking vacuum. No leaks detected, pull valve cover and adjust valves. Valve adjustment is key. Valve adjustment procedures can be found in FAQ, shop manual or by asking someone to find you that thread. :cheers:
The ppp
 

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