I have a 70 J-3000 with a Buick 350, and it runs great when it is in park and neutral, but soon as you get it under a load it dosen't wanna work. It will run for about half a mile then just stutter really bad and die. Also I have no brake lights, I've looked all over the place and there is no place where any electrical things touch the brake system.
I am completly lost.thanks for any help!!!!!!

"Unpassable when wet"????? Whatever

Hey, i am not the most knowledgable person for help, but for what it is worth....
1-the brake lights- i would check to see if you have any juice at the light sockets, (maybe just the bulbs are out) make sure it is grounded, also there must be a switch to send the message to activate the lights when you apply brake pressure. Maybe that switch failed. I dunno where it is though.
2-Engine rough under load- So many things it could be. How long has it done this? Did you do any work on before it acted up that may have caused this when you put it back together? Something silly like wrong spark plug wire going to wrong plug may cause it (ask me how i know...). The more info you provide on it, the more likely somebody here can help you out. Good Luck!

look underneath the brake master cylinder (MC) the brake light switch is screwed into the bottom of it.

if the engine runs fine on light load and not at all under any load, than i wood suspect fuel pressure.

under light load there is little need for full volume of fuel, but under driveing conditions, the need for fuel is great, (of corse), check to make sure u have enuff VOLUME AND PRESSURE from the fuel pump and that all filters and lines are unobstructed.

next time u ahve the engine running, as soon as it dies, pull somewhere safe and imediatly check 2c if any fuel is in the carb by removing the air cleaner, starring down the throats of the carb and moving the throttle linkage.

there shood be 2 distinctive streams of fuel present when u do this, if not, fuel starvation is the prob.

do u smell alot of fuel when the engine dies?? if so than perhaps ur getting too much fuel to the carb and are flooding out. if the float mech within the carb is compromised than it cant meter fuel properly.

are the motor mounts bad??? if they are, the engine cood move while under load and temporarly disconnect or ground the elec system to the plugs.

Well when I first bought it about a year ago it ran great and I drove it all around town, and just in the past few weeks, mabey a month it has been dying, I am trying to sell it to someone and it died on the way to his house(talk about embarassing!!!). I think that I heard there is a valve inside the carb that when the engine is under load it opens up to allow more fuel and if it is not driven it could dry up and become warped. I dont know if that would have anything to do with it.Also I went to the auto parts store and asked for a brake sensor and it was hydrolic, so I will look under the mc. I really dont know if I should sell it and am having major doubts. Thanks for your guys help, and let me know if you think that I should keep it. I am really unsure. Thanks again.

"Unpassable when wet"????? Whatever

On your truck, the brake switch is on the brake line disribution block. Should be one the framerail just under the steering column. Just follow the brake lines from the master cylinder until you find it.
You should have the Rochester 2G carb on your 350. These are so simple to rebuild and the kit is around $8. I'd give it a shot. Some other things to check too are vacuum leaks at the carb base gasket, intake manfold, and all hoses.

Well I did follow the lines, and all they do is go from the bottom of the mc, and to a T where they go to the front, and to the rear where they split at another T for the rear brakes. There is no way to put a sensor on there that I could see.I havent got a chance to look under the mc yet but if it is there, how would i hook those up to the lights?
I think that you must be right that I should re-build the carb(because it is easy and cheap). I was wanting to get a new manifold and put a 4bbl. Edelbrock 650. But I dont know where to get a new manifold for this truck. Thanks you guys for all your help, you are awsome!!
thanks

"Unpassable when wet"????? Whatever

You may want to make sure you have enough fluid in the tranny. A simple thing like not enough fluid can cause the tranny not to down shift to the lower gear. Your kick-down cable may also be out of adjustment--play around with it. Move it back away from the carb and forward, checking the results each time you drive. It may solve your problem.

Also--how many miles are on it? The engine may be tired.

Is there any stray connector in the area of the junction block? Or maybe someone cut the wires. It should be a flat 2-spade connector either near the master cyl if that's where the switch is or near the junction. I thought all the FSJ wiring was unchanged through '72 so it must be there somewhere. Does the junction block have an extra threaded connection that's plugged off maybe?

Chris

If you want to keep the truck and are still considering uping to the 4bbl intake and edelbrock 650, you can get the intake either from Poston $259 P/N PE236 1-800-635-9781 or from TA Performance $275 P/N TA 1235 1-480-922-6807. I bought the TA manifold just cause I heard it was better and was quite thrilled with the performance jump that came with it and the edelbrock - but if your fixin to sell it save yer dinero!

Brian D. RdHawg
70 Wagoneer w/350 buick v8

Hey guys, I know that the truck was originaly bought in Anchorage Alaska, so naturaly it must have an ass-load of miles. I haven't really been able to look at it to much in the past couple of days(seeing that it is broken down in front of some guys house) but I know that it is all good on tranny fluid, It very well could be the down shift cable, I'll have to check it. Ans as far as I can remember Chris, is that the lines comedown from the mc, and the front lines spilt, and the rear stays togather until they split at the rear axel, I plan on checking under the master cylender tommorow. The guy who is looking at buying it has been playing around with it and I just wanna know if you guys think that I should sell it or not.Thanks for your help again!!!


"Unpassable when wet"????? Whatever