Stall and bogging= total shutoff? (1 Viewer)

[YangFJ40]

Driving on the freeway for the first time in my recently rebuilt motor. Going to college at Sacramento State and took a 4 hour drive to get here. While at a rest stop I noticed the bogging. The car bogs on acceleration but is fine at high rpm that is why I didn't notice it for so long until I lost all power on the highway and swung over. I assumed it was bad gas but put 91 from chevron and it does the same thing. Any ideas???? 1978 FJ40 2f RV cam hei distributor weber vacumn advanced

 

[78fj40mg]

It could be a carb issue and/or as simple as a clogged fuel fuel filter. Is this a new issue or an existing one that's progressively getting worse?

 

[YangFJ40]

It could be a carb issue and/or as simple as a clogged fuel fuel filter. Is this a new issue or an existing one that's progressively getting worse?

The bogging started today it has never done this before

 

[78fj40mg]

Start with easy stuff first, have you changed the fuel filter recently?

 

[YangFJ40]

About a year ago

 

[78fj40mg]

OK, does it still idle?
When the engine is idling if you floor the accelerator does it stall?

 

[edwjmcgrath]

Change the fuel filter. The symptoms are classic.
If you've got an inline filter, I recommend a transparent one so that you can kind of keep an eye on what's happening.
If you've got rust or sediment in an older gas tank, it can clog up in a day.

 

[Josie'sLandCruiser]

Hi all,

This definitely sounds like a fuel system issue from my experience (i.e. crap in the gas tank.)

The OE Toyota fuel filter looks cool (metal cylinder) but with a carburetor or TBI it is a low pressure system. I use a Wix model 33002 clear plastic fuel filter which is good quality and is not that expensive yet allows one can observe the fuel inside the filter.

Regards,

Alan

 

[YangFJ40]

Hey guys sorru didn't get back I've been loaded down. Anyways seafoamed the car and loaded the carb with cleaner and changed the fuel filter out. Same symptoms as before any thoughts?

 

[Pin_Head]

A more detailed description of the "bogging" problem might help because bogging means different things in different circumstances.
Fuel starvation / fuel deliver problems typically cause bucking and backfiring through the carb but not "bogging".
Things to check:
Does the accelerator pump squirt gas into the primary when you open the throttle?
Does it idle OK or do you need to pull the choke to keep it running?

I worked my way through a degree at Sac State as a mechanic.

 

[YangFJ40]

Idles perfect and drives fine only bucks in low rpms. Sounds like a miss almost. Also only bucks when it's in the running temperature area. When it's cold it's fine. Also in neutral it runs perfect. No choke is needed except to start

 

[edwjmcgrath]

This is confusing. You say that it lost all power on the highway and you pulled over. Then you say that it works fine at high rpm's.

I think that maybe what you are saying is that when you transition from idle to a higher speed you have a lack of power as it comes off idle and starts to speed up. Is that it? What happened on the highway and is that the same problem you are trying to describe?

 

[lcwizard]

I've had vapor lock issues with every Weber I've used in hot climates.
I'm in Az so it's not like I can avoid the heat. You'll notice it most after running at temperature
for a while. Pulling an incline makes it worse while it will improve on flats and downhills.
If these are the symptoms the best way to fix is to install a return line.. The most foolproof I found was
a hi flow electrc style pump and a pressure regulator with a return and mount the regulator and return as close to the carb as possible.. The firewall is good. With this, even running at temp, the fuel in the lines is cool to touch at the return line

 

[YangFJ40]

This is confusing. You say that it lost all power on the highway and you pulled over. Then you say that it works fine at high rpm's.

I think that maybe what you are saying is that when you transition from idle to a higher speed you have a lack of power as it comes off idle and starts to speed up. Is that it? What happened on the highway and is that the same problem you are trying to describe?

The highway thing was what it seems to be a one time thing. You are right when coming out of idle it has the symptoms described

 

[edwjmcgrath]

This could be one of a few things, but I'll mention a couple.

Look down the throat of the carb with the engine off. Operate the throttle and look for a good squirt of gas. The part that gives that squirt is the accelerator pump. If it doesn't work, it will tend to bog when you try to accelerate either from idle or at speed. If it bogs on acceleration at all speeds then it may be the accelerator pump.

It could also be a carb adjustment problem or a mal adjusted carb due to a vacuum leak. What is your vacuum at idle?