Stalls after acceleration when dropping to idle

[Pearly]

Can anyone help - garage can't find solution. I have a 3 l rb30 petrol motor. It stalls when I come to a stop if I take out of gear. It's intermittent and appears to happen when hot. The hand throttle pulled to spin it over at about 2000 rpm appears to be the only way I can stop her from stalling. I'm guessing its probable a needle in carby issue or a diaphragm ?? Can anyone help? It's driving me mad as when she stalls I lose power steering - no fun at all !

[93patrol]

sounds like you need a carbie kit through it mate they are about $80-100 or you can hand it over to a mechanic and get them to do it, I just ordered a 330 holley from ebay and whacked it on still needed a final tune though from someone more experienced than me on this sort of caper

[lucus30]

Don't have LPG and a snorkel do you?

[mudnut]

The second stage of the carby can stick in various positions and cause problems too. Does it flood, (black smoke) or starve for fuel?

[Pearly]

Thanks guys. Interesting it starts ok after stall but you have to put your foot to the floor like trying to start a flooded engine .... Also along those lines and something that makes scense now, when you take foot off the gas and just let it idle going down hill after she's worked hard getting up it, she occasionally backfires - so maybe it is a flooding problem ?. If so where should I look first? And no I don't have snorkel yet or LPG - thanks all what a great forum!!

[mudnut]

Could be a bit of foreign material in the needle and seat, or the float is split.

The Haynes manual list: Idle speed incorrect, clogged fuel filter, or water in the fuel, choke not operating correctly, damaged distributor, faulty emission system, incorrect spark plug gap, vacuum leak and also incorrect valve clearance, (but RB30 has overhead cam, so not relevant unless lifters or camshaft are worn).

Easy to do stuff : Try a cup of metho in the fuel tank or put some injector/carby cleaner in the fuel.

Check the distributor, for eroded or burnt metal and that there is no signs of moisture or cracks. Check the rotor button, making sure the overspeed spring is working and that the outer edge isn't eroded or deformed.

Take the top off the air filter housing and make sure all the linkages and choke are working. Change fuel filter.

Clean the sight glass in the front of the carby, and see that the fuel level isn't too high or too low.

Move all the linkages and make sure that the second stage butterfly is able to move easily throughout its range.

Tape up the unconnected hose connections. With the engine idling, spray wd40 or crc around the inlet manifold, (especially the gasket). If the spray is sucked in anywhere the revs will increase.

Check all of the electrical connections (especially earths and battery terminals).

Check all the High tension leads.

Check the spark plug gaps (.8 to.9 mm).

Have a look at this thread: http://www.nissanpatrol.com.au/forum...-Helpful-Hints

[GQ TANK]

My tb42 has a simalar issue when I first got ir - then it stoped working on petrol.

I ut a kit though the carby.

The rb30s and tb42s carbys are basically the same - they even use the same kit.

[huardlc]

hi mate seems like your engine timing is completely out of wack...

[Patrol'n]

I have an RB30 patrol and this weekend I have experienced similar issues as you described, where the engine would drop revs and stall if I put the clutch in and let the revs fall and wouldn't idle. It also did the backfire when going down the hill as you described, what did the problem turn out to be?

Any help would be greatly appreciated, right now it's running fine again, it just seemed to happen for a while then go away again, then come back at random.

Thanks, I was ready to park it in the lake yesterday it was winding me up that badly...

[mudnut]

Have you gone over
the above list?
Mine has started
to backfire on start up
but intermittently.
Intermittent faults are
the worst!!!!!
I replaced the leads
and fixed a lot of
problems a few
months ago.