[rfrey]

Yea, I can take it down the block, and to the store, but if I go too far, or if it doesn't get to stop and rest long enough it dies...It is very hard to get started again, and sometimes will with a lot of gas, and a very long starter crank...but it dies again soon after that.
Can you tell me what the problem is, and how to fix it?

Do you think it might be vacuum lock? And how do you fix that? (I was told the gas was getting too hot while in the hose before reaching the engine...)?

Thanks...I need to fix this fast....

 

[TPIJeep]

Do you mean vapor lock? Gas boiling in carb bowl? That is possible, EGR valve do you have one? Is it stuck?

Option to, carb spacer, try and get a 1" aluminium carb spacer to help sheild the carb from the heat a bit.

There are alot of things it could be..

But it would be nice to know if this is the engine for the rig that you want help getting it together or not? If its a carbed 350 my answer applies, if its a fuel injected TBI please let us know.

 

[reddwarf]

Bad coil or module going bad(module will soon let you know by giving up entirely)

bad fuel pump

Choke sticking

vacuum leak

some things to check for

 

[slopoke]

have you had the motor in before and it just started doing this, or did you just swap it, and its doing this. if it jsut started and was fine before i would lean towards the coil going bad. when they get hot they can lose spark. it doesnt sound like its vacume because it would run bad all the time. if this is a new swap it could be fuel vapor lock, there fore liek said above get a 1 inch aluminum carb spacer. check those first, scott

 

[patooyee]

I had a similar problem on a 258 of mine. It was a new engine after a rebuild. It turned out to be the fuel filter getting clogged. It would run until enogh crap built up inside of it to stop it, and then it would stop and be hard to start. (It would soud like it was sucking air as it stopped.) If I let it sit for a while, the sediment in the filter would settle to the bottom and I could start it again, but not long because it would happen again. I worked on it for weeks before I changed the fuel filter, thinking it was too simple of a fix to create the problem. It clogged a few more filter before I got all the shit out of the tank. but by my 3rd filter it never happened again. Not saying that this IS your problem, it's just a possibility. I thought my problem was heat at first, too. But it wasn't.

J. J.

 

[horse_with_no_name]

I would suspect that the fuel pump is bad, try checking the fuel pressure at the schrader valve. I don't know the specs right off hand, but can tell you that the 4.3 tbi pump needs @13, and the 4.3 vortec needs @50. Just ask the Manager at autozone in Vista
about how mad someone can be when they are sold the tbi pump for a vortec application! Most chevy pumps are lucky to last 100,000 miles before they do what you are describing. Run out of gas a few times and suck some bad mojo in the pump and it shortens the life of the pump greatly. If your truck is tbi Napa has a frame rail mounted tbi pump that can replace the in tank unit, and make trail fixes etc. much easier.

 

[rfrey]

Sorry for not getting back to you guys earlier.

It is a Holly Carbed 350. The motor is older, and probibly slightly tired. I talked to a guy last night (who probibly knows nothing), but he said it may be the floats, and to have the carb rebuilt.

I think I am going to start by replacing the filter.

The coke is not hooked up, so I don't think it is that.

I bought the rig running like this, so I don't know how it ran before, but I would suspect (from the looks of the motor), that it had worked fine for some time.

It seems like it is getting gas...so I think the pump might be my last bet, but I also think it is a manual pump (the one that bolts to the front passengers side of the block).

I am also not sure what EGR valve it has...well, I am not sure what an EGR valve is, so I couldn't tell you.

Keep the info coming...I really appreciate it.

Thank you

 

[Buddha's Ghost]

Bad coil or module going bad(module will soon let you know by giving up entirely)

I'd have to say this is one good bet. Have you checked for spark immediately after this happens?

 

[rfrey]

I hate to ask this, but how do you check for spark? What is the quickest easiest way to do this while the motor is hot?

 

[LordRatner]

I hate to ask this, but how do you check for spark? What is the quickest easiest way to do this while the motor is hot?

I just wet my hands and touch the distributor terminals, but it hurts like hell

 

[Buddha's Ghost]

I hate to ask this, but how do you check for spark? What is the quickest easiest way to do this while the motor is hot?

Pull a plug wire and hold it in your mouth.


Just kidding. Pull one and hold it near a good ground on the engine. The spark will jump across when you turn the engine over.

 

[SilverZuk]

Too much fuel
(or not enough fire)

It's loading up and flooding.
Common problem with holleys.

Tune up will help, and a better coil.
But the problem is likely too much fuel.
You need to keep it "cleaned out" (had to do it all the time on street rods).
Kick it neutral and rev it up periodically.

It probably runs great on the top end, doesn't it.
If so, that's your problem.
If so, you might want to change the carb to a smaller one (500 cfm).

You can rejet, but holleys only seem to work well in wide open applications.
Change out the fuel jet with a smaller one.
If you have anymore input let us know.
Good luck.

After reading your first post again -- If it doesn't run good on top end or starts to die when you pull a hill, it's too little fuel.
Change the fuel filter, check the pressure.

 

[slopoke]

yea when it starts to die pull the easist plug to get to connect the wire to it and teh either hold the threads of the plug on the block and look at the spark on hold it near a ground and it will arc to it. i prefer to hold it to the block because you can see what the spark of the plug actually looks like, instead of it arc'ing. look at the color of the spark, if its orange or weak in general it could be a bad coil. you want a nice white, blue spark

 

[ForestCam]

Just something outta left field but seeing as how it's an older engine you could have a badly worn timing chain causing the timing to advance when the engine is warm.
I had one years ago that just plain wouldn't start when it was warm, timing would advance so far it acted like the battery was dead and the only way to start it was let it sit for an hour.

 

[rfrey]

Yea, it seems like when I run to the store and black...5 miles or so...I have all sorts of problems, but when I jump on the freeway...last time I went 25 or so miles with no problems. I exited the freeway... four or five stop signs later, it wants to die. I can get it going again if I keep on the starter and the gas pedal. Then it has a tough time getting going again....but if I get up to speed...top of the gear it doesn't seem to have as much trouble. However, after it has died three or four times, it won't start again...I have to let it sit...and yes it acts like I am out of gas...

OK, it's a Holley carb, and has an adjustment screw on the front of the carb on each side. My buddy said to screw them all the way in and back them out 1.25 turns. I did this and the motor seemed to run better, but the thing still dies????

Sorry, I know nothing of Carbs...please more help!!!

Oh, I changed the fuel filter, and I think it went a little further, but still died.

I think I might check the spark next... Please keep the info coming.

 

[slopoke]

on the adjustment screws on the carb, let the engine idle and screw one side in at a time. keep going until you notice a change in teh engine, it will start to idle down. stop and turn it back to just before it starts to idle down, this will give you a good lean mixture. do this on each side, then see how it does. CHECK THE SPARK!

 

[rfrey]

Ok...I tried screwing it! I must really suck at screwing, because I got absolutly nowhere!

I tried pulling a plug wire (#3) and putting it next to the block to alow it to spark. I was told to look for a blue spark verses a orange one. Well, I got [email protected] shocked out of me! I decided that I could stand it one more time, and cranked it over...nothing. I did it again, and...almost nothing. Then I did it again, and a nice blue streak surrounded by an orange layer presented itself.

So, what do you guys think?

There is somewhat of an exhaust leak...do you think it could be that?

Help please. This thing is not running well, and I want to play with it!

Thanks.

 

[HNRYS69]

gotta be spark... Put a screw driver in a plug boot and place it near metal, turn over, you should hear or see the blue spark. And it should always spark, not sometimes.

 

[patooyee]

gotta be spark... Put a screw driver in a plug boot and place it near metal, turn over, you should hear or see the blue spark. And it should always spark, not sometimes.

Well if he's not turning it over enough, not doing a full rotation, it won't always spark.

J. J.

 

[rfrey]

I may not have turned it all the way over....I was worried about getting shocked.


I would say that it was blue....what is the next diagnostic?