I've got the results somewhere, I'll try to find them... I'm the worst record keeper.

They didn't check the dist. but its fairly new so it should be OK.
I'll check for leaks. The truck runs smoothly unless idleing or going up a hill, it's idle is pretty high and rough. Tried lowering the idle speed but then it ran real rough or stalled out.

Heres a quote from a site I was reading
"A rough idle or stalling. A performance cam with lots of valve overlap can give an engine a lopping idle, but so can a vacuum leak. A really serious leak can lean the air/fuel mixture out to such an extent that an engine won't idle at all. An EGR valve that is stuck open at idle can have the same effect as a vacuum leak. So too can the wrong PCV valve (one that flows too much air for the application), or a loose PCV hose. The rough idle in these cases is caused by "lean misfire." The fuel mixture is too lean to ignite reliably so it often misfires and fails to ignite at all. Lean misfire will show up as elevated hydrocarbon (HC) readings in the exhaust, enough, in fact, to cause a vehicle to fail an emissions test. "
Engine Vacuum Leaks

That is what it sounds like.. Again, i'll look for leaks and have my shop take a peek. It's entirely possible that the hoses are bad..

By engine condition I assume you mean the physical condition? The engines condition isn't bad. Heck, you can still see the original paint in spots. No leaks anywhere, doesn't burn oil, overall in good shape. When it's not idling (or going up a hill) runs great. Runs quieltly (unless idling) and smoothly.

 

I have the feeling whatever is causing the power loss is a minor thing.

Not that this is your problem ...Some people don't realize a plugged CC can cause no power and make the manifold glow red.

Vacuum leaks are a major cause of engine not running right.
Bad spark at plugs
Bad Gasoline
Bad Vacuum advance not allowing timing to change for higher RPM
Choke stuck on.



1) Check the idle air/fuel mixture screws for correct adjustment.
2) Does choke butterfly open all the way when engine hot ?

 

I'm wondering about the knocking rattling and pinging. Have you verified that your base timing is correct, and that the vacuum advance line is connected to the correct port on the carburetor? That could certainly explain your loss of power, as well.

 

check your vacuum hoses yourself. see if they're cracked, etc. you can easily replace them yourself. Get a haynes or chilton manual and start reading.

 

If you are at all concerned about gas mileage I would not recommend swapping in a 302. I would almost swear my neighbors are syphoning out my gas With your pinging issues have you checked your timing? Also everyone who posted before me has some good suggestions for seeing if you can improve your current engine before jumping into getting a new one.

 

I checked the vacuum hoses, no obvious leaks anywhere. Didn't see any cracking, they look to be in good shape. That said, there obviously could still be a leak somewhere that I'm just not seeing.

The knocking and pinging is my main worry at the moment. Timing has been checked more then once, that was the first thing we checked. It doesn't knock nearly as badly with supreme gas.. But I cant afford that all the time. The vacuum advanced line is connected properly as well.

I've got a haynes manual, i'll dig into it a bit deeper. I've just skimmed it so far.

 

i will go out on a limb but if it is not burning any oil it is not worn out.

 

I think you are missing some of the info we are trying got provide.

Vacuum hoses : This is not just a visual thing, Take an unlit propane torch and point it towards ALL vacuum fittings and hose connections.The engine will speed up where there is a leak.

Is the vacuum advance new as well or JUST the distributor ?

The engine has to be timed with regular fuel not premium.

Is there an EGR under the carb ?

When you remove a spark plug what do you see where the electrodes are?

Brown,white,black,wet with fuel or oil ?

 

^^I dont doubt I'm missing info, I'm trying! Remember, this is my first vehicle, only other vehicle i've ever worked on is a 99 corolla. I haven't had anyone around to teach me anything, i'm learning mainly by reading. So please bear with me.

I did know that about the hoses, didn't have time to check today but will forsure another day. I just checked for obvious leaks, there was none.

Not positive about the Vacuum advanced, it was done before I owned the vehicle.

Engine was timed with regular fuel, I put premium in for the first time ever the other day. My shops suggestion for aircare and to help reduce the noise.

Spark plugs were done awhile ago, I haven't checked recently. They are due to be changed. I'll check for all that.


Kim

 

At idle, do as Dennis has said and use an un-lit propane torch or spray carburator cleaner around all vacuum hoses, the base of the carburator, all around the intake manifold and brake booster lines. If your idle smooths out you have found your leak and it should be an easy fix.

If your truck is pinging when accelerating or going up hill, that leads me to believe you have a timing issue. I would ditch the timing light and try adjusting it by ear. That may also clear up your rough idle. Timing is also altitude sensitive. If you bought your truck from a high elevation and live in a lower area, you will get pinging. I had a car that ran great in the college town I lived in (5000')but would sound like the engine was going to explode when I went to visit my folks at 1100 feet elevation. In my limited experiance a pinging engine has plenty of compression so I don't think your engine is wore out. If your not burning a lot of oil that is also a good sign.

I would hesitate on changing engines, from what you are saying I think a little time and a couple hundred dollars (or less, maybe a lot less) would have your truck running in tip top shape. If your engine is running properly I think your trany problems will be gone as well.

A good running 300 in a 2WD truck should get you in the low to mid 20's in MPG

 

id stick w the 300.it has more torque at lower rpms which would make it a better working truck being in the city.it also is a much tougher engine than a 351,or even a 460

 

I had a 77 with a 300, and by experiance, I can say it got great milege, and tons of pulling power, and fantastic throttle response. 351 W are good for fast accelleration, but weak for pulling - I owned an 87 F150 351W... Didn't fit my style. I also have a 79 F150 with a 351M I will be pulling out since I just got a rebuilt, and pepped up, 400M. I love the power of the V8, but if I had a 300 again, I wouldn't change a thing. Have it poperly rebuilt, and request the head be shaved .015" - .020", without a thicker head gasket. This does two things, it insures a flat, smooth mating surface for your head gasket, and will increase your compression a bit, which will improve power and milege! Don't shave off more than .025" or you will be buying Premium every trip to the gas station, in fact too much and you will be into raceing fuel. Also, rebuild or replace that carburetor. A stock, or aftermarket very close to stock cam will work best. Valve train noise is common, so research cam makers websites, and get advice on which are quieter. ALWAYS install a HIGH volume oil pump with ANY rebuild, and include a high pressure relief spring. There's my 2 cents worth, happy motoring...

 

Thanks guys.
I was told my truck was a california truck. I'm in BC, I dont think the elevation is much different. That said, I live nextdoor to the rockies so EVERYWHERE you drive the elevation changes.

I went up to my shop yesterday, they only had time to check timing by ear. They did make some minor adjustments and it is running with more power, but still not as much as it should have. I havent taken on the highway yet, we'll see how the pinging sounds.

The thing is, when we adjust it so the idle isn't rough it drives like garbage. Seems to be one or the other, either a nice idle and regular stalling OR a rough idle and a decent drive. I'll forsure check for vacuum leaks.

 

There's the problem all that CA emissions crap and BC's clean air crap.

Bring to me and leave it for a week and see what I can do for it.

Where is BC are you ?

 

I didn't know about CA emission laws, havent looked into it. We basically 'cheated' air care... Failed first time due to crud in the engine at idle. We adjusted it so it would run hot and burn up the crud (ran AWFUL) and it passed with flying colours. Then we switched it back and its back to it's old self.. lol

I'm just outside of Vancouver