Vapor lock? (1 Viewer)

[JasonFJ40]

Newbie question for you Cruiser gods out there. A buddy of mine and I were out driving around in my 78 FJ40 for about 20 minutes or so and it was running like a champ. We got back to his place, drank a beer then I got back in the Cruiser to come home. When I tried to start it, it turned over but sounds pretty rough. It'll start and run for a while but almost feels like it's missing when it's in lower RPM's. If I slowly give it some gas, it seems to run good as the RPM's climb, but as soon as I put any load on the engine it dies. Does this sound like vapor lock?

The temperature out here in Ohio is in the mid 60's, so I don't know what to think about vapor lock. The Cruiser doesn't seem like it's running hot and the temp gauge is reading good. Any thoughts?

One other thing: It turns over strong, but a couple of times it felt like the battery was going to die.....like it was hesitating when trying to turn the motor over. Could this indicate ignition/electrical issues?

Thanks in advance!

 

[zetasig]

I dont think it would be hot enought to vapor lock. it sounds like it might be something with the carb. Was it rebuilt ever? Maybe a clogged fuel filter, or worn out accelerator pump.

Just curious where in OHIO?

If it is a carb problem Jim C. is in Lancaster OH. Great guy and knows everthing about carbs..

As for the slow turning over, Check and clean all of your cables, and grounds. Maybe a weak battery or a dying starter.

Warren.

 

[jesterb]

My 3FE started doing the same thing last weekend. Mine was a bad alternator. I'm replacing it tonight.

 

[JasonFJ40]

Update: I ran down to my buddy's house this morning to see if the Cruiser would run. I hopped in, it started right up and drove home without any problems at all....

zetasig: I'm in the Cincinnati area. I usually do some hunting near the Lancaster area in the fall, so I might look Jim C. up. Your advice about possible carb issues and fuel filter is a good thoght. I'll change out the filter this week as I don't know how old it is (Just got this Cruiser a couple of months ago). The PO replaced the stock carb with a Weber some time ago. I think I'm having other issues related to the carb and need someone like Jim C. to steer me in the right direction!

 

[zetasig]

Most or some will tell you dump the weber. Jim C, works with the Asian (stock) carbs.

Great guy.

good luck. Warren.

 

[treerootCO]

I have only seen this problem on my 1978 FJ40. All the other Cruisers I have owned have never had this problem. The fix is simple....go buy any other year Cruiser

Here is a list of what will not fix the problem. Save your pennies

• New OEM fuel pump

• Electric pusher before the mechanical

• New fuel lines

• New filter

• New carb

• Fuel pressure regulator

• New gaskets to seal off any vacuum leaks (helped out in the end so this wouldn't hurt)

• Pulled the tank and cleaned it

• Insulation on the lines near the engine

• Getting towed by the state patrol because the median is not a place to park your truck

What does fix the problem, aside from an exorcism, is to pull your gas cap the next time it happens. You will hear a rush of air going into the tank. You or the PO probably capped off the vent line at some point in the Cruiser's life. Look under the passenger rocker...you will see a hard line running up to the firewall next to the body mount. Then, inside the engine compartment, next to the brake lines you will see the hard line reemerging from the firewall. The line passes through the body mount. It will change to a rubber line and at the end, check to see how the line is capped off. Bonus OEM metric bolt, crappy SAE grade 3, golf tee, channel locks maybe. That would be sweet. I call it the drinking straw theory....acts just like covering the end of a drinking straw as you pull the straw out of a refreshing beverage. Do not unplug this line and let it hang lower then the tank. This will create a siphon and dump all your gas out the bottom of the truck (ask me how I know... ) Charcoal canister is the best fix hooked up to the carb and it may even net you a mpg gain in fuel savings

 

[mloudy]

Mine will do this after I drive from place to place, shutting off and coming back later to drive. It doesn't do it all the time. Usually after at least 2 plus stops and starts. Mine starts fine but once I drive about 50 feet it dies. Push the pedal to the floor and it starts after about 5 seconds of cranking and it then sputters until I get going in 4th gear to about 45mph. It runs fine the rest of the time. Now it's 80 in Ohio but give it a day and it will change again.

 

[JasonFJ40]

treerootCO: Thanks for the laundry list of what not to try! I'll look for the golf tee. In a sick sort of way, I'm kind looking forward to it happening again so I can try the gas cap trick.

I think I'll run the alternator down to Autozone to have it checked just for giggles.

 

[Land Bruiser]

Im having the same fawking problem with my 1969 FJ55.... Sometimes it will run fine, and other times it just dies... When it is acting up, it wil start right back up every time only to die again, and once in a while will run fine for almost an hour, before reverting back to the dying crap.. I have replaced the fuel filter, fuel pump, coil, cleaned entire fuse box and put dilectric grease on contacts, replaced battery, tried running it with gas cap off, tried running it with wire directly to coil from battery,relaced battery cables, sent a crapload of carb cleaner through it, opened carb and checked everything, and checked the plugs and points... A year ago it had the following done, new alternator, new cap, new rotor, new points, new plugs, carb rebuild, oil change, ect (which all still look new).. I put few miles on it after that. It has sat in my dry garage since last sept., but has been started and idled every other month, sometimes more... I pulled her out a few weeks back to start wheeling again, and it cut out a few times, which has turned in to alot more than cutting out, and alot more often over the past few weeks of taking her out. I have ran about 20 gallons of gas through her since then, till the problem got so bad, I cant drive it anymore with out fear of being stranded somewhere (usually not too far).. I have even tried adding a water remover to the gas tank, and also a few system cleaner for carberated vehicles.. The frustration is killing me...
BTW -- Im running a chevy 292 in it with a rochester single barrel carb.. Maybe my problem is c-h-e-v-y..... My other 55 has never done this, but has stock F motor.. lol.. Then again, the thing used to run fine.. Any ideas are greatly appreciated..

 

[bigbrowndog]

Have you guys released your filler cap when this happens to see if the tank is venting and has not built up a vacuum in the tank?

 

[Land Bruiser]

Yes..

 

[okie]

My 3FE started doing the same thing last weekend. Mine was a bad alternator. I'm replacing it tonight.

i second that . this EXACT same thing happened to my camaro. It was just a bad /old alternator.