1984 Chevy Pickup-no power

[Shrubby]

My 1984 Chevy pickup truck with a 305 4-barrel and three speed automatic transmission has no power.
It has about 144,000 miles on it.
It has good compression and about 30-pounds of oil pressure.
The truck doesn't have enought power to pull itself up on a pair of car ramps.
How do I tell if it's a flat cam or the torque converter/transmission is bad?
Thanks for your help.
Shrubby

[bmauto]

check your catalytic convertor

[Shrubby]

Got a brand new cat on it about one year ago when I bought the truck.
I was leaning towards the transmission since the truck has a little power after it warms up.
But after talking to a Chevy man with 30 years experience-after he drove it he thinks it's a flat cam.
I don't want to replace the cam and find it's the tranny.

[bduff509]

Check your vacuum. That should give you a fair idea if it's the cam. Check all of your vacuum lines for leaks first.

[okie-chevy-man]

first check your tranny fluid. is it full? when is the last time you changed the filter in it? do it cause it propably needs done. does it backfire any? does it miss any?
Look at the bright side, if it is the cam at least it is cheap and easy to replace. now you have an excuse to get that wild cam you wanted.

[Shrubby]

The transmission fluid and filter was changed a few months ago.
Originally it had a problem shifting into third (Drive) but after a can of Seafoam it cleared up.
I then changed the fluid and filter.
I keep it full (not overfilled).
I tightened the carb bolts to the manifold. They were loose and the backfireing stopped.
Put a new rotor and cap on it too.
This thing doesn't have enought power to get out of a small water hole.
I'm not kidding.
It just has no power.
It's like there is no fluid in the transmission whatsoever.
I will check the vacuum this weekend.
How much should it have.
It has between 30-45 pounds of oil pressure.
It's got new plugs but I am planning on putting new wires on it.
It's got an exhaust leak on the left side but that shouldn't keep it from having enought power to get the front end up on a set of car ramps.
Any more ideas?

[amac209]

did you check the timing? does it missfire?? is the choke fully opening? does the accelerator pump give it a good shot of fuel then the throttle is opened. usually the fuel filter at the carb is plugged when this happens with a rochester carb. could also be fuel pump. if all this stuff is good try adjusting the valves. if you have a flat cam it will be obvious.heres how to adjust the valves: remove a valve cover, start the engine and loosen one of the rockers until You hear it just start to "clatter". Slowly tighten it down until the "clatter" just stops and then turn it 1/4 - 1/2 turn additional. do this for each rocker arm one at a time. good luck!!

[Shrubby]

When it warms up the choke is open. I put in a new fuel filter and fuel line from the pump to the carb. Had to. Somebody didn't use a flaring wrench and the fuel line was nearly cracked into near the fitting.
The accelerator pump shoots two good streams while the engine is off.
Put a new cap and rotor on it. Plug wires are next.
Tightened the carb bolts down becaue they were loose and it was backfiring a little.
The engine revs up good in park.
But the engine trys to die when in reverse or forward when accelerating. The truck just won't pull itself. I'm leaning towards the torque converter.
The transmission has 140,000 miles on it.
It didn't shift into third when I bought the truck one year ago but some Seafoam cured that. I then changed the filter and fluid.
I had to put a new catalitic converter on it because Missouri requires it.
Could the cat be plugged up already?
It's a real small one not like the big, flat ones from the old days.

[amac209]

a vacuum gage is the best way to figure out whats going on. does it smoke a lot??? one way of testing the cat is to temporarily unhook it. check the carb for loading up. sometimes crap gets stuck in the passeges, try reving it up in park then pull the choke closed open it back up just before it dies do this 5 or 6 times it will pull a whole bunch of gas through the jets and sometimes uncloggs them. does it backfire before it dies?? i assume you have a TH-350 tranny check the vacuum modulator hose for cracks or tranny fluid in the line. check the bolts on the fuel pump sometimes they back out. maybe take another look at the fuel filter try to blow through it. does it drive if you put in in 1st or 2nd? check for vacuum leaks too, wd-40 works good just spray it around the gaskets and lines. does it roll in neutral?? brakes might be locked up. have a look at those rocker arms.
good luck!!!

[desertmike1]

Good job amac209, but don't forget the timing chain!

[Shrubby]

Thanks guys.
You've been a big help.
I'll get on it this weekend.

[30yrnavy]

Sounds like you received a lot of good advice. Check one simple thing next though before you start digging too deep into the problem. A bad vacuum advance (diaphram stuck but not leaking) will cause exactly the problem you're experiencing. This will not show up as a vacuum leak so can be easily overlooked. If it's stuck your points won't advance your timing under load during acceleration which will give you a lack of power. Simple to check: remove the distributor cap, remove the vacuum line from the engine (not the diaphram), suck on it and see if the points move around the cam. It they don't then either the diaphram is stuck or the plate that the points mount on is stuck. I hope that's your problem...it's the cheapest thing to fix!

[amac209]

thats a good point 30yrnavy . just rev it up while the timing lights on it should go to around 30 degrees advanced at about 3500rpm if not the centrifugal advance is stuck the vacuum advance might make a little difference if it's stuck but not much. that truck should have a HEI(high energy ignition) distributor so no points to worry about.