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Engine wont catch


DatMo

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I need some help.  

 

I have an L16 in my 71' 521 with a weber carb (32/36).  So far I have replaced the carb, fuel pump,spark plugs, ignition wires, ignition coil, and installed an electric distributor.  

 

I swapped out the carb first because my old stock carb needed a rebuild, and my engine wasnt starting after it sat for so long.  When i replaced it, the truck started right up, and I drove it to work the next morning no problem.  However, when i was leaving work the same day, i went to start the truck and it started right up once again, but as i was letting it warm up, it died after about 2 minutes. When i went to restart it, it kept turning over but wouldnt catch (sounded like a fuel problem).  Thought maybe my fuel gage was messed up so i put more gas and used some starter fluid to get it fired up again.  Once again, started right up.  Later I tested the fuel pump suction and it felt pretty weak, so i decided to replace it.  

 

I just replaced it today, went to start it, and it started right up.  I decided to let it stay on for about 10 minutes before i turned it off to fix the brakes, a few hours later i went to start it up again, and it wasnt catching once again.  I put starter fluid and it hardly catches, then dies immediately, OR when i press gas.  I dont understand whats wrong, is it the carb again? it ran perfectly fine when i took it and brought it back to work. When i press gas, it immediately boggles and dies quick, then makes a weird sucking sound from the carb.

 

 

PS- This is Datmo's brother, thanks

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He's not. He's real. And 18, if that helps. 

 

DatMo is real. Been around a while. 

19 and 20 this saturday. lol

 

sorry he just lost his account info because he made one years ago and he tried sending it to his email but it was asking for his user name which he forgot as well.

 

So should he drain out his tank and blow out the lines?

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Blow the line from the pump to the tank. See how it runs after. 

 

 

But cleaning out the tank is a fine idea. How does the fuel filter look?

 

 

 

 

What's the deal with your car, Dat?

 

Well my car is for sure the tranny issue being stuck in gear. I'm hoping this weekend since i got the night off for my birthday to take it off or inspect it some more and fix the problem.

I'm figuring out an idea for a front bench seat and picked up a nice set of riverside riverges yesterday but my phone wouldnt connect to the comp to post some pics. 

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Alright you guys, sorry for the mix up, I am DatMo's brother. I didn't want to make another account but I also don't want my brother getting in trouble on his either. I apologize.

 

Anyways, the fuel filter looks fine, I think the last possible problem would be the lines getting clogged, so I'll get on that tomorrow. Anything else you guys suggest?

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Email pics to yourself. Load to computer from email.

 

That's how I roll.

I tried but somehow my iPhone won't let me? That's how I used to do it on my old phone but this iPhone shit makes it complicated and they won't seem to send. They'll send to people's #'s just not emails
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Next time it's hard to re-start, take air filter off and look in it while pumping throttle. If you don't see gas squirting from the accelerator pump the carb is dry. If you see gas then it's not a fuel problem.

 

Tested fuel pump suction? Test for fuel delivery. Is the pump .... pumping fuel?

 

Take the fuel line off the carb end and direct into a suitable container. Crank engine over with the starter. You should observe strong squirts of fuel.

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He changed to many stuff at once to figure all this out with no results.

 

hard for a weber to go bad unless it was another junk.

 

not hard to ck the fuel pump. Put the out put hose off and start the car the gas shoould be SHOOTING OUT.

 

if filter clean(tear it open then gas tank is fine)

 

Ck for gas pumping in carb.

 

maybe carb is loose and the intsake manifold loose. tighten

 

Why you change all the ignition? Just place wire to ground and see if sparks. yes or NO.

 

then ck the valve lash. lash good. then ck the dist timming.

 

This should fire.

 

if coil was change you put correct coil for the electronic ignition? coil feels HOT

 

 

Datmo should have anwsered all this already with out going on the computer

 

 

choke stays on to long. Ectric or manual choke?

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datzenmike: So I usually have the air filter off as im shooting the starter fluid, but I have not looked into the carb that deep while it is running, I dont think its safe to look down into it when the engine is running, for it might shoot stuff/air out at any time, right?. And I will try the fuel pump, although I'm almost positive its fine because I just replaced it yesterday.  But even if the fuel pump is working, will it still have fuel coming out if the lines are clogged? I am currently at work so I cant give a pic, but the truck came with this weird metal box in the bed that the owner said has something to do with the fuel and air? I plan on removing that once i figure that out. i will post it later

 

kelowg: I did the conversoin and bought a larger coil, it works fine. The truck was plenty cool (sat for about 2 hours while I did brakes), so the coil should have been fiine.

 

banzai510(hainz): I have changed many things, but not all at once.  I changed the coil about a 2 months ago, had an electric dizzy with it but turns out it was bad.  I then changed the carb and dizzy about 2 weeks ago, and puel pump yesterday. For the fuel pump, the reason why i didnt check if fuel was coming out was bc i was scared the lines were clogged.  So i assumed that the pump was letting fuel if the "IN" hose was forming a suction.  Carb and manifold are both tight, already checked that.  I am positive ignition is not the problem, I changed it because the points dizzy wasnt hitting right and causing the truck to run really bad. I dont know what the valve lash is, where is that located? Coil is also good, im positivie of that as well. I worked on the truck on my own last night, as soon as he got home, i asked him to make the post. He's worked on it with me before, we couldnt figure it out. And as for the choke, Im almost positive its electric choke, i hooked up power to it from the coil.

 

I am still confused how it can be any of these issues, ther than the clogged line/fuel tank, because is was running perfect after every upgrade i was installing.  I plan to put a clear fuel filter eventually as well.

 

BTW, i am new to the carb'd engine scene. I bought this truck because it was a great deal.

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I changed it because the points dizzy wasnt hitting right and causing the truck to run really bad. ??????? condensor?

 

so you sure the new distributor was installed at TDC and timmed right?

YOu have a timming light and gpt it to say 5-12degs for it to run?

 

Fuel Pump?

If you pull the out put line and gas shoots out while cranking it over . Thats all you need to know the pump works. I seen where the line is cracked on the INout side causeing it NO vaccum to suck gas in.

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Loosen the dizzy from the small bolt where you do the timing adjustment, turn the damn dizzy all the way left (counter clockwise) have someone turn the ignition and at some point when gas goes in the carb it should want to fire, but THAT will happen if everything else is in order, you need to have proper gas pressure going into the carb, carb needs to have the foundation adjustment and you need good spark, it's really not that hard, it's not firing up because something is NOT right.

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banzai510(hainz): Whether is was the condesor or not, I wanted to switch over to electric distributor anyways, I personally think its a lot easier and less of a hassle.  I did install it at TDC, however, I did not have a timing light, so no it was not timed.  And once again, if their isnt any fuel reaching the pump to begin with (maybe due to a clogged lines from the tank), then it would look like the pump wasnt pumping (because no fuel will be coming out), so i tested for suction instead, not fuel.  I will try out the fuel test as mentioned earlier. I really dont think its the ignition that is the problem. I could be wrong, but im almost positive.

 

flatcat19: Its a rebuilt stock electric distributor from a later model 620 I believe.

 

KoHeartsGPA: Like I said to banzai510(hainz), I really dont think its the ignition thats the issue here. I will try this out as a very last resort, because i already know the carb is not receiving proper amounts of fuel. 

 

Maybe it has been over read, but the truck will still start up (hardly) when i spray starter fluid. I dont think that it would do that if fuel was able to naturally be sent to the carb, or if the ignition was bad. Once again, maybe I am wrong about that.  If i give it gas while it is still on by pulling the throttle, it will boggle and die, BUT if i do the same but spray the fluid in at the same time, then it revs fine until the fluid is used up, then it dies unless i keep spraying. It really seems like gas isnt reaching the carb for whatever reason...

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OK you open up the fuel filter?

521s the filler hose the calmp get get loose and let water in the tank and rust.

 

Pump ther carb and seee if it squirts gas. If not then the aceel pump on carb is bad or no fuel in the float bowl. or the needle valve is stuck closed not letting gas in. Cause be rust , but more likel to keep the valve from closing causing a FLOOD condition

 

This is all if the. fuel pump works.

 

if it fires will starting fluid or gas poured from top I assume the ignition is fine.

 

maybe tighten carb if anything else.

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banzai510(hainz): Can you explain that second line you wrote, I couldnt understand with all the typos, but it seems like you maybe on to something if the rust is clogging the lines. Also, the carb doesnt have a window for fuel level like that of the stock one. I think that needle valve might also be a possiblity.  How do you repair a flooded carb?  

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