YACT: I'm pissed. Update: I fixed it. Christ.

[Eli]

OK, so as many of you know.. I've been having my truck worked on a lot.

It was all drivetrain work, I didn't have them touch the engine.

The engine has been running a little rough when cold, but it clears right up when it warms up..

So I had them do a tuneup.

They adjusted the timing(which they said was way off..... ), and adjusted the carburetor.

Now it has NO power. Nothing like it used to. Not even close. It doesen't sound the same, it doesen't open up the same.. It's like a completely different engine.

I am at a loss for what to do. They worked on it for free today. Said that the vacuum advance diaphram wasn't working correctly. So they replaced that, and it is a little better.. but it's still NOTHING like it used to be.

The worst part is that they're all "Yeah, it seems to have great power, running great..." and I'm like "Yeah, well you cocksuckers didn't drive it before I let you put your grubby hands all over the engine". :roll:

They just don't get it since they don't know what it was like before. I want to call them back up and be like "It's NOT right", but it's getting to the point now where I feel annoying and I don't think they believe me or don't quite understand what I'm trying to convey.

At wide open throttle, it used to have a mean growl. It sounds like it does when it's running cold now, even when warm. It's like the secondaries aren't opening at all.

Help! I need a Chevy 350 guru or something. This sucks. I give up with this shop, they don't know what they're doing.

:|

If I had a second car I would fiddle with it myself, but I have to be able to get to work.

Update: Well, christ. At least it was something simple.

The PCV hose was indeed rubbing up against the linkages, and it was preventing the secondaries from opening.

What a difference. It's much better now. I'd need to go out on the highway to really see if the top end is better, but I was able to squeek the tires when I went into 2nd gear without really even trying.. It was pretty hard before.

 

[Heisenberg]

Carburetor huh? *shudders* I still think it's a minor miracle those things work at all.

I guess I'd start by checking the timing and making sure the vacuum advance is working. Then adjust the carb yourself.

Edit: I replied before your edit. Nevermind then I guess...

 

[Eli]

Originally posted by: Heisenberg
Carburetor huh? *shudders* I still think it's a minor miracle those things work at all.

I guess I'd start by checking the timing and making sure the vacuum advance is working. Then adjust the carb yourself.

When those secondaries opened before, there was a HUGE surge in power. Now it does nothing when I put my foot to the floor. No growl, nothing...

They checked and rechecked the timing. He said that it was set to TDC before.

I wish I knew more about how this engine was built and setup before.

I just want to take it back and be like "Undo everything, I want it the way it was before".

 

[MikeMike]

take it to a seperate mechanic, who knows Carbs better?

 

[Heisenberg]

Maybe they just misadjusted one of the linkages in the carb? Does it run smoothly other than the lack in power? I'd think that if the timing was too far out of whack, it'd be really rough.

 

[iamaelephant]

What sort of carb is on it? Sounds like a possible vacuum leak, but you say they adjusted the timing? They probably stuffed it up. It's possible that the balancer has spun slightly so they thought they were getting the timing right but it's off. You'll need to find true TDC on the balancer, which is fairly easy to do. The best way to do it is to get someone to weld a small nut onto the end of a spark plug, screw it into No. 1 cylinder. Turn the engine clockwise by hand (carefully!!) until the piston just touches the nut on the end of the plug. Mark the balancer where the arrow is pointing. Now turn the engine carefully counter clockwise until it hits the nut again, and mark the balancer. Exactly in between those two marks on the balancer is true TDC. Now use a protractor to find the real timing marks on your balancer, set the timing to where you want it and you will know 100% for sure that the timing is right, provided the vacuum diaphram is in good condition and the mechanical advance springs aren't broken.

 

[Eli]

Originally posted by: MIKEMIKE
take it to a seperate mechanic, who knows Carbs better?

I'm completely broke now.

I'm afraid that is what I'm going to have to do though.

I paid them 70$ for a tuneup though. It should have more, or at least the same power that it did before they touched it.. Not less.

That isn't right.

 

[Eli]

Originally posted by: Falcon39
What sort of carb is on it? Sounds like a possible vacuum leak, but you say they adjusted the timing? They probably stuffed it up. It's possible that the balancer has spun slightly so they thought they were getting the timing right but it's off. You'll need to find true TDC on the balancer, which is fairly easy to do. The best way to do it is to get someone to weld a small nut onto the end of a spark plug, screw it into No. 1 cylinder. Turn the engine clockwise by hand (carefully!!) until the piston just touches the nut on the end of the plug. Mark the balancer where the arrow is pointing. Now turn the engine carefully counter clockwise until it hits the nut again, and mark the balancer. Exactly in between those two marks on the balancer is true TDC. Now use a protractor to find the real timing marks on your balancer, set the timing to where you want it and you will know 100% for sure that the timing is right, provided the vacuum diaphram is in good condition and the mechanical advance springs aren't broken.

I don't have time for that kind've ******.

 

[Eli]

Originally posted by: Heisenberg
Maybe they just misadjusted one of the linkages in the carb? Does it run smoothly other than the lack in power? I'd think that if the timing was too far out of whack, it'd be really rough.

It seems to be running OK, but it ran OK before.. just not while cold.

 

[iamaelephant]

Well short of replacing the balancer ($$$$) unfortunately that's the only way of knowing if you're on true TDC. You could just play around with the timing for a bit until it feels a little better, but this often ends badly (you often make it worse).

 

[Eli]

Hmm..

Definitely something with the secondary's not opening. Looks like maybe the PCV hose was touching some linkages and causing them to bind.

They only barely peek open when I blip the throttle, they used to pop right open. Going to go fiddle with it some more....

 

[Eli]

Originally posted by: Falcon39
Well short of replacing the balancer ($$$$) unfortunately that's the only way of knowing if you're on true TDC. You could just play around with the timing for a bit until it feels a little better, but this often ends badly (you often make it worse).

I am VERY curious as to why the timing was set to TDC before they messed with it.

You would think that'd make the engine run like sh!t, especially when any advance kicks in.

WTF???

They've got it set to the stock setting of 10º BTDC now.

 

[Kilgor]

Did they adjust the Air/fuel ratio? Maybe you need to adjust the accelerator pump.

 

[zanieladie]

Oh man...that soooooo sux. Sorry...

 

[Eli]

Originally posted by: Kilgor
Did they adjust the Air/fuel ratio? Maybe you need to adjust the accelerator pump.

I'm not exactly sure what they did with the carb, but yeah.. they probably did.

It was tuned by a professional Chevy guy before. It had just started running a little rough when cold the last few months, and maybe a small loss in power when warm.

So I did all the routine stuff.. plugs, wires, distributor cap/rotor.. and it still persisted.

So I was like "meh, I'll have them do it since it's in the shop aready."

It made me nervous, but I just trusted they would know what they were doing. Apparently that was a mistake and I should've gone with my intuition.

The big, big mistake was that they did not drive it while warm before they worked on the engine. I really thought about requesting that they let it warm up and then take it on the highway as a test run, instead of just going around the block. Now I really, really wish they would have. They just don't get it.

I wanted to show them the videos I made, so they could at least hear what it sounded like before.. and get an idea of acceleration. But not only did they look at me like I was crazy.. even though they have a small "internet cafe" in the lobby of the office, the computers didn't have speakers. :roll:

Geesh, what a clusterfsck. I knew it, I really did.. I ignored my feeling and figured they would know what they are doing.

 

[Ktulu]

I think you need a :beer:

GL with your 350

 

[Ornery]

Check the linkage on the choke pull-off. It won't allow the secondaries to open until it's warmed up.

 

[Eli]

Well, christ. At least it was something simple.

The PCV hose was indeed rubbing up against the linkages, and it was preventing the secondaries from opening.

What a difference. It's much better now. I'd need to go out on the highway to really see if the top end is better, but I was able to squeek the tires when I went into 2nd without really even trying.. It was pretty hard before.

 

[iamaelephant]

Excellent to hear it was something simple!

 

[OrganizedChaos]

glad to here it was something simple. those chevy carbs are supose to be somewhat reasonable to work on. i have a friend with a 1990 police package crown vic. with the motorcraft 7200 variable venturi carb. you can stare at that thing for hours without ever figuring out how it works.

 

[iamaelephant]

1990 and still with a carb? WTF?!

 

[ElFenix]

glad you fixed it

 

[RossMAN]

Which hwy are you going to test it out on?

If it's I-205 I'll steer clear of it this weekend

 

[Eli]

Originally posted by: RossMAN
Which hwy are you going to test it out on?

If it's I-205 I'll steer clear of it this weekend

Probably all over. lol