85 TBI with I think a 305? Cranks fooooorever

[Mike85Silverado]

So i just bought an 85 silverado about a month ago.  I know nothing about cars or trucks except how to do an oil/filter change basically.  Im hoping to learn a little with this truck.  The PO put in a TBI system and new fuel pump about a year ago (he gave me the receipts).  When I go to start the truck, it cranks for a looong time before starting.  Once its started, it runs and idles perfectly. The battery is about a year old too... Any ideas?
I asked a mechanic that just replaced my lower control arm bushings and he said it might be a problem with the fuel pressure? but he would have to do a lot to check it out, and i dont have the money right now...
Thanks guys, I love this site already!

[bd]

What brand TBI - factory or aftermarket?  Fuel pressure is the first thing to check.  Factory TBI uses ~11 PSI.  You should hear a 'factory fuel pump' run for about 2 seconds and then stop, immediately after switching the ignition ON, w/o cranking the engine.  This primes and pressurizes the fuel system for quick start-up.

[Mike85Silverado]

I honestly don't know what brand or whatever the fuel pump is.  The receipt doesn't say.  I always hear the fuel pump run for a couple seconds when I turn ignition to "on" position. It still cranks for awhile though before firing up...

[bd]

Does the throttle body have Rochester cast into it?  Can you post an image?
You should begin by measuring the fuel pressure - check the fuel filter while you're at it.

[Mike85Silverado]

ok dont be mad but,
1) where is the thottle body? where would a rochester be cast into it?
2) how do i measure fuel pressure?
3) where is the fuel filter?

I know....... im learning though haha

[bd]

The throttle body sits right on top of the engine, underneath the air cleaner.  Remove the air cleaner and snap a picture.

[Captkaos]

Factory (and most basic aftermarket TBI's) look like this:

[Mike85Silverado]

hey chris, the other day i removed my air cleaner and saw something that looked like the picture you posted. Im working all weekend but ill take a pic of it next week and show you guys

[Stewart G Griffin]

i don't think 85 came with tbi.  We need a picture.

[winky]

^^ I THiNK I've seen an 85 work truck with stock throttle body. Sounds like your fuel pump isn't holding pressure. Everyone is sending you in the right direction. Try turning the key to "on" then "off" a few times and try cranking it and see if it starts up any quicker. Also look around under the air filter and see if you see something that kinda looks like a valve stem (the thing where you put air in your tires) if you see something like that under there then that's where you check your fuel pressure. Also one it cranks up and runs for a little bit if you shut it off will it crank right back up or still hesitate to start?

[Mike85Silverado]

It didn't come with a TBI, the PO had one put in. It can be running and then ill turn it off and if I try to start it right back up, it still cranks for awhile.
I tried something new last night though and I'm not sure if it was a fluke but it worked.
Instead of waiting to hear the fuel pump stop after turning key to on position, to start my truck, I cranked it about 3/4 of the way through the fuel pump noise, and it fired right up...
Ill try it again tomorrow and let you know.
Could the pressure be up when the fuel pump is going, but the go back down once the fuel pump noise stops and that be making it hesitate?

[bd]

You really need to find out what's going on with your fuel pressure, even if you have to have someone else check it.  Report the pre-crank fuel pressure with the key ON; the engine running fuel pressure; and ~20 seconds of the post-running fuel pressure right after the engine is shut OFF and the fuel pump quits running.  We still would like an image of the throttle body, if possible....

[winky]

Sounds like fuel pressure but like bd said you need to check it. And yes your fuel pump should have a valve that keeps pressure on the lines if it fails you will lose pressure untill the pump is running

[Mike85Silverado]

Any estimates on how much you guys think it would cost to get looked at or fixed?

[Mike85Silverado]

Do you guys have any idea how much it would cost to get checked out? Or fixed?