350 vortec 5.7 lower intake leaking vacuum?? Help please

[SirRobyn0]

Ok you have gotten a lot of good advice, so I won't duplicate any of that, but I'll try to mention only stuff that has not been mentioned.

Obviously you had issues with the intake and you are getting that taken care of which is great. Getting the updated spider injection is a must do, I'd put a new fuel filter on it to.

But the vortecs with the pancake style ignition cap are known for failing in weird ways. Everything from hard starting to sudden misfires and backfiring. Can happen on a cap of literally any age or mileage. At the shop we will only use ACDelco cap & rotor as they are the only brand that doesn't seem to do this. I only mention this so if you get it back together and it still isn't running like it should, this would be a good next step.

Oh and for the record, I think that the stock vortec's are great motors, but just like any other motor they have their idiosyncrasies. I've got a 1999 454 vortec in a class c RV. Also I would not hesitate to own a truck with 5.7 vortec.

 

[squaredeal91]

@SirRobyn0 here's the automotive small engine filter.

 

[HotWheelsBurban]

Ok you have gotten a lot of good advice, so I won't duplicate any of that, but I'll try to mention only stuff that has not been mentioned.

Obviously you had issues with the intake and you are getting that taken care of which is great. Getting the updated spider injection is a must do, I'd put a new fuel filter on it to.

But the vortecs with the pancake style ignition cap are known for failing in weird ways. Everything from hard starting to sudden misfires and backfiring. Can happen on a cap of literally any age or mileage. At the shop we will only use ACDelco cap & rotor as they are the only brand that doesn't seem to do this. I only mention this so if you get it back together and it still isn't running like it should, this would be a good next step.

Oh and for the record, I think that the stock vortec's are great motors, but just like any other motor they have their idiosyncrasies. I've got a 1999 454 vortec in a class c RV. Also I would not hesitate to own a truck with 5.7 vortec.

I have had great luck with the United Motor Products blue vented cap and rotor, both with brass contacts, on both my Vortec 350/5.7 trucks. I grew up watching Dad use Blue Streak caps and rotors on our vehicles. He was a big Delco Remy user, but we sold both brands at our parts store. The Vortecs have a problem with humidity collecting in the cap, and corroding the aluminum contacts. So the vent keeps the humidity from collecting, and the brass contacts don't corrode like the aluminum ones. The other thing you have to watch for is that the #5 and #7 can misfire if the wires touch, or the cap gets cracked or corroded around the terminal bridges inside the cap.

 

[SirRobyn0]

@SirRobyn0 here's the automotive small engine filter.

I have those on the shelf at the shop, I had noticed sometime back that they'd physically fit a small engine, just never knew if it was ok, thank you!

 

[squaredeal91]

I have those on the shelf at the shop, I had noticed sometime back that they'd physically fit a small engine, just never knew if it was ok, thank you!

I think what matters is if it's a low bypass or not maybe?

 

[SirRobyn0]

I think what matters is if it's a low bypass or not maybe?

IDK, but I have that exact filter you mentioned so I guess I'll give those a try and see how they work out.

 

[RanchWelder]

Just to be clear the injector set is referred to as a "nut set" in the manual. No idea why?

The "spider" is technically the metal spring bracket that holds the roller lifter retaining keepers in place.
With too much cam and improper push rod lengths or weak springs, (such as under loaded springs), the spider can "float".

When this happens the roller lifters may rotate sideways to the lifter keepers and very quickly turn into solid lifters.

Checked with R/A for the part numbers on the 5.7L EGR, to see if the EGR pulled from the 7.4L 99' K2500 would fit your rig.
The part numbers for the 5.7L are completely different.

They look the same, the plug has 5 pins and looks the same, but they call for different parts.
No-go.

If you use a big can of carb cleaner and soak the valve, it should be OK.
When the EGR fails to work or gets clogged, it usually will stall and bog badly.
Used a really small flat blade and a set of picks to clean the carbon out after soaking anually on my EGR.

you can usually push on the pintal and see if the spring moves the piston and closes properly.
The cheap one is $68, so try not to break it. ACDelco wants $124 P/S.

 

[squaredeal91]

Here's what I'm waiting for in the mail. Legs are alot different from original. Looks like they will fit tight in there holes. Originals were a sloppy and has lots of space around.

 

[idahovette]

@squaredeal91 I HATE sloppy.......

 

[squaredeal91]

@squaredeal91 I HATE sloppy.......

If it ain't tight, it ain't right!

 

[bucket]

All this talk of spider injectors reminded me of a funny Napa commercial with Michael Waltrip. They had several commercials that featured a certain part and the injector spider one was quite funny. I couldn't find it on YouTube though.

However, I inevitably went down the YouTube rabbit hole and came across this one that I had forgotten about.

xc_hide_links_from_guests_guests_error_hide_media

 

[squaredeal91]

Eight legged freak!!!!!

 

[squaredeal91]

Also new coolant temp sensor and new tps. Seems to be running good again! Engine itself is quieter probably the valve adjustment did that. It's pretty smooth I'd say. I'm happy with it.

Ps: this thing is running 4°cam advance and no check engine light. Only side affect is its better on fuel because it has lots of torque
and the cap and rotor need cleaned more often. I'm cool with the better mileage lol.

 

[squaredeal91]

I wasn't counting but because I took my time and did extra things I'd say a 12 pack job maybe.

 

[RanchWelder]

They call that injection system "The Toilet".
(It's where your money goes re-purchasing that injector pod... hahahah).
It's a good system, I'm only having fun with you...

Word of advice?
Double check the valves and timing after driving 30 days or 500 miles.

Look for the loose push rod, with too much slop or the rocker arm wobble.

If you find even 1 sloppy rocker... you should consider taller Vortec center bolt valve covers and a quality set of Comp rocker lock nuts or crush the loose nuts, SLIGHTLY, with a vice.
(Obviously, bump through the entire line and re-set the valve lash and pre-load.)

1 sloppy valve will ruin that engine, most likely from 1-2 low grade imported steel 3/8" studs in those heads.
You drop a valve, collapse a lifter or loose a weakened spring; your done.
Crappy threads at the point they need to grab the lock nuts, will loosen up again.

Adjusting the valves is fun, after a few times. Dropping the wrench or the Allen Key, is to be avoided at all cost.
No Coors during the valve adjustments. You leave the wrenches in there and you'll be very angry.
You spill a Coors and you'll lose it!