PO botched carb?! Help Please

That retainer for the pcv is actually rubber, and it must be a tight fit!!!!

That is a very common issue! It's referred to as a "pcv grommet" and is not commonly available any longer in any parts house (except "maybe" and IH/navistar dealer).

I have some of those here (new). Since I'm sending you this envelope in about an hour, I'll throw one in. Then you can call Jeff and settle with him as it's a normal ihon stocking item. Ya caught me just in time!
 
michael mayben said:
...plug the fuel line where it goes into the carb so it can't squirt fuel. Crank the engine over several times (pull the coil wire out first!) and you will see mt. St. Helens erupt from those two holes! Use vacuum again to pull any remaining particles outta the plenum, ya don't want that stuff going into the combustion chambers!
Click to expand...

I've got a mech. Fuel pump...is there any concern about back pressure busting the diaphragm? The pump is only a couple months old but just had to ask
 
Sweet!

Yeah I guess rubber does turn to "plastic" in 30+years

well I'm either shortening the problem list or jumping further down the rabbit's hole :gringrin:

your time and help is invaluable..thanks again!
 
You won't hurt the fuel pump, it's "rated" output is 5.5psi +/1 1psi, that is a "standard" for the Holley carburetor feed.

It won't take but a few cranks to blow that schnizz out! Push the diaphragm "open" while cranking so the exhaust "pulse" can blow through the passages.

I'm outta here until after midnite!
 
Alright, got the plenum holes cleaned out, the pcv tube back into the manifold nice and snug, and the old grommet out

question on the egr valve...is the diaphragm bottom supposed to be flush with the dividing slots? It was about a finger's width "open"...guess I was expecting to feel it flush with the slots, so I'm just curious if its stuck in an open position or always like that

thanks
 
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Nope, the diaphragm is not flush with the slots when not applied. Your description sounds correct. But...particles of carbon cause the pintle to not seat correctly resulting in the vacuum leak at idle (actually egr partially open).

If in doubt, remove the two bolts that hold the egr valve in place and remove/clean. The replacement gasket for that is a fel-pro 70978 used in many acura, GM, Nissan, Jeep, saturn apps. Egr valve service is a periodic maintenance kinda thing.
 
Will the egr valve's open position provide an audible hiss?

I've heard one ever since my Scout has been running.

Be checking that one tomorrow. Perhaps I'll remove carburetor and try rigging up a 2x12 for "bench" work, too.

:dita: it's good to live bbs free, I've decided.
 
If you can detect a "hiss" around the egr valve, it's most likely a perforated vacuum motor diaphragm. That means the egr valve is non-func and ya have a vacuum leak when there is an egr apply signal provided in the vacuum circuitry.

A hand held vacuum pump is an essential tool for working with many of the systems on these old motors! Ya can rig one to the port on the egr and simply apply a vacuum with the engine idling. If the idle quality goes to hell, then the egr is functioning. If it won't actuate off the pump, then the diaphragm is perforated/rotted, and ya won't be able to apply a vacuum and have the egr valve "hold open" since the vacuum motor has failed.

The el cheepocheeseball way of testing this??? Put a length of appropriate vacuum tubing directly on the egr valve nipple. Start the engine. Then suk bigtime on the hose until yore eyes pop out. If the idle quality goes to hell and maybe the engine even stalls, then the egr is operational (but the valve pintle and seat May be grunged up). If ya suk and suk and nothing happens, then the valve diaphragm is perforated.

Use that same chunk of vacuum tubing for a poorboy stethoscope to seek out engine noises such as the "hiss" you describe. Stick one end (the clean end!) in yore best ear! Use the other to probe around suspected areas of vacuum leakage, etc. You will hear problem areas greatly amplified in this manner. Be careful, do not stick the hose in yore ear so far it comes out the other side! We can't fix that in cyberspace.
 
michael mayben said:
if in doubt, remove the two bolts that hold the egr valve in place and remove/clean. The replacement gasket for that is a fel-pro 70978 used in many acura, GM, Nissan, Jeep, saturn apps. Egr valve service is a periodic maintenance kinda thing.
Click to expand...

Dont want to get too far off topic for this thread, but would you recommend just blocking off the egr?
 
Let me see if I'm learning here....

Since I'm running a 2210/2245 "smogerator" its "set up" to run with the egr system = lean

so to maybe answer my own question, if the egr is working properly than its best to keep it on?
 
Ryan...discussion of issues such as egr or modifications to any component or the complete emissions systems on any vehicle is kind of a gray area, even for a 30+ year old junker being resurrected from the boneyard (figuratively thinking of course!)! And that is a practice the state of kalifornia (and many others!) does not want free-thinking folks to play with as a hobby/special interest.

Discussing proper service and parts replacement techniques is certainly ok! But we gotta be real careful here in bs'n about "mods" which would be performed only "for off-highway vehicle use".

So...I'm sending you an private email regarding my opinion only! Not trying to dodge the bullet...but there is a major reason for being careful about this stuff! I can only trust ya don't work for the epa suits/spooks that run this kuntry!

I will say this...finding the correct replacement service part egr valve for any IH application has become an extremely difficult issue to deal with in the last few years. Parts that were readily available off-the-shelf at any parts house just a few years ago, are now nla from their respective manufacturers/distributors, the old story of supply (there is none), vs. Demand (there is none)! There were many individual p/n egr valves used across the board just on the sv engine, add in all the other IH engine apps and the problem is greatly magnified. Then add in the "evolved" egr apps that came into play around '76 and beyond and the problem becomes much more complicated.

That's my tap dance for the week!
 
Understand completely!!! I'll look for that email and appreciate your time on that question

probably start with removal/cleaning/new gasket..local store's got that felpro for $0.99

do you recommend just careful cleaning of the ports on the egr, or is there any liquid solution safe for that diaphragm?
 
No liquid needed to clean the egr valve. Once ya get it off and move the diaphragm with your fingers, you will fully understand how all this schnizz works!

I hold the pintle open and use a rotary wire brush in my drill press to buff the carbon accumulation away if needed. Sometimes there is no accumulation, but if the egr has never been serviced, it will look like the gates of hell in there!

Ya should have the email right now if nancy pelosi has not turned off the I-net.
 
Haha...looks like we're still up and running for now

I did get the email! Thank you!

Picked up a gasket at lunch..get that cleaned out this evening and keep moving forward
 
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