rebuilt engine in, but only runs in spurts

[cell]

Ok guys, so I got my inline 6 back from the machine shop and back in the truck. Problem is, I can't get it to run for more than a few seconds.

In order to get it to start to turn over, I have to pump the gas a couple of times. Then, it will run for about 5 seconds, but then dies.

I find that if I pump the gas about once or twice every few seconds, I can get it to run for about 30 seconds. However, backfiring becomes a problem, and it dies.

background: this truck ran when I got it, but I haven't rebuilt the carb, and the carb hasn't been used since I tore the engine apart, several months ago.

I have a carb rebuild kit, but I wanted to at least get it running before I tore that apart as well (I didn't want to change too many variables at once). Do I need to just go ahead and rebuild the carb?



thanks guys.

[Steelawork'n]

This might sound kind of funny but did you open up the valves before trying to start it? The machine shop won't adjust them cause that is done by the mechanic installing the engine.

[truckdude239]

sounds like a bad carb to me

[rage'nrat638]

second the carb or fuel delivery problem

[Longhorn Man]

check your fuel pump or fuel lines.

[67Mach1]

Jason, My Suburban did the same thing until I put a rebuilt carb on it two weeks ago. Fired right up after that. One thing I did was choke the carb down all the way and it seemed to start better then I simply replaced it.

Throw the rebuild kit on or go to Oreillys and get the premium rebuilt carb. It is hit or miss with them but they will warranty them if you have a problem.

Glad to see you are making progress.

Thomas

[cell]

Hey Thomas, I saw your post about the big brown suburban. What a cool project! Oddly enough, a guy just moved in down the street from me with a late 60's suburban.

Well, I started tearing into it. I'll post again tomorrow night after I have it reassembled and give my starter another workout

[cell]

wow, this guy was having what sounds like the exact same problem I am having.

http://www.67-72chevytrucks.com/vboa...1&postcount=33

he mentions the fuel pump as being part of the problem, and I have no idea how old my fuel pump is. advance auto has them for $11, so I'll go ahead and replace that too.

http://www.partsamerica.com/ProductD...ype=52&ptset=A

[89 crew]

Originally Posted by 67Mach1

Jason, My Suburban did the same thing until I put a rebuilt carb on it two weeks ago. Fired right up after that. One thing I did was choke the carb down all the way and it seemed to start better then I simply replaced it.

Throw the rebuild kit on or go to Oreillys and get the premium rebuilt carb. It is hit or miss with them but they will warranty them if you have a problem.

Glad to see you are making progress.

Thomas

You had better check those carbs for metal grindings. I have bought carbs at Oreillys 3 times and and all 3 had grindings left in them! The first time I trusted them. and yes they did waranty it. The next two times I didn't trust them and opened the new carbs up. cleaned out the metal and all was good from there!

[67Mach1]

Jason, I had wondered the same thing and picked up a fuel pump from the parts store also. but like you said, testing one thing at a time I put on carb and gave it a few cranks.

Mine was solved w/out haveing to replace it but I decided to keep the pump just in case... Yeah, I decided I needed somethign that was closer to being road worthy and found the sub by accident. they are pretty cool when done right. That and yousimply dont see them anywhere.

89CREW- Heck, even the Oreillys guys warned me about he carbs, I ended up payin more and got he Holley brand rebuilt one and so far hve been lucky. Have not put the sub on the road yet as i am still rebuilding brakes. Once that is done I will put carb though its paces. Thanks for the warning.

Thomas

[cell]

Hmm, time to update this thread.

rebuilt the carb, replaced fuel pump, replaced plugs, wires, dist cap, rotor, condesor, and points. All of those parts were just so cheap I figured "why not?".

In the end, it turned out my timing was just way too retarded. I had a friend come over and he rotated the distributor back and forth while I cranked and cranked until we got it to turn over. We dialed in the distributor rotation until it "sounded right", then I got out my timing gun and set it to 4 degrees advanced. It has run like a champ ever since! I am almost at 500 miles, and am about to have my first oil change.

However, I still need to tweak the fuel air mixture. I can smell unburnt gas in the exhaust, and I calculated just under 8 mpg consistently over 3 tanks of gas.

[shelby987]

Glad to hear you got it running, I found this thread, and was going to post a link to my problem, but looks like you beat me to it.

I can tell you, you have to be running rich at under 8mpg, with my 1bbl I avg'd 11mpg city, and 13mpg. highway. 4bbl I eek out 13~14mpg city or highway with 4.56's on a 4x4.

[truckeez]

HEY Cell- Truckeez here-also known as******* on the benz site, I have been lurking here and just signed up, I got the 292 from you last summer- and am considering using a 3 ltr merc in my coe. I think the problen was the fuel pump--The auto parts store rebuilt ones put out about 9 psi when only 3 max is needed-even for a quadrajet-They leak internally when over pumped. i saw on Super T D how you had scored a sprinter turbo-cool! Some may think its crazy to try to power a monster like the

http://www.peachparts.com/shopforum/...9&d=1241051085

im gonna try to find the modern turbo and an intercooler-turn up the pump a little --and should be able to get up to the power level of a sprinter moter, it wont be a speed demon-but i should make it affordable to operate-That means a nv4500 to 617 conversion bell, but thats a different subject!