Where is my EGR valve?

Aaarrghh · June 11, 2016, 09:41 PM

I have an issue with hesitation/stalling on acceleration after a stop. The manual lists a stuck EGR valve as one of the possible causes. I want to start there, because I've never checked it.

I know it's a dumb question, but I've looked through the manual and searched Google, searched this forum, and asked at O'Reillys. It's supposed to be on the passenger side, back of the carburetor, on the intake manifold. Here's a picture. Do you see it? (Nevermind the grunge -its an old picture, taken before I did anything). There's no vacuum hose for it, and none pictured in the emissions hose diagram.

EldoradoBill · June 11, 2016, 10:32 PM

On a stock engine it would be at the back of the engine (out of the shot you posted) but something seems odd about that intake manifold....

BrianB · June 11, 2016, 10:50 PM

Are you sure your engine has an EGR valve? I don't see it on the emissions diagram.

Aaarrghh · June 12, 2016, 02:39 AM

Quote from: BrianB on June 11, 2016, 10:50 PM
Are you sure your engine has an EGR valve? I don't see it on the emissions diagram.

No, not sure, but I thought every engine used EGR. Just assumed mine does.

Rickf1985 · June 12, 2016, 11:07 AM

I don't see the egr and it is not on the diagram so it probably doers not have it but there are a few things I do see, the main one being the TVS just laying out there with lines hooked up but not threaded into the manifold. Kind of hard to tell with all the rust what exactly I am looking to tell the truth. Was this vehicle under water? Do you have a pic after it has been cleaned up.

M & J · June 12, 2016, 12:39 PM

He probably removed it from the air cleaner when he removed it instead of pulling the vacuum lines Rick.

Aaarrghh · June 12, 2016, 03:54 PM

So, is the consensus that this motor does NOT use exhaust gas re-circulation?

Aaarrghh · June 12, 2016, 04:21 PM

Here's a better view of a nearly identical motor, in a truck at the junkyard. Where's the EGR valve?

Rickf1985 · June 12, 2016, 05:17 PM

The EGR on 1975 up through the mid eighties was on a machined casting on the passenger side of the intake manifold right behind the choke heater casting. It is not on either of the engines you show probably due to the weight rating of the vehicle the engines were installed in.

And the picture of yours with the squirrels nest is a classic!! :)rotflmao :)rotflmao :)rotflmao :)rotflmao Now I understand the rust! Gallons of squirrel piss! D:oH!

Aaarrghh · June 12, 2016, 07:16 PM

Thanks. I'll go with that answer.

Rickf1985 · June 12, 2016, 09:47 PM

On the serious side, If you had that much or a squirrel issue you need to go over every inch of the wiring on that RV. You do not want to find the chewed wires as the magic smoke is coming out at 60 MPH on the interstate!

TerryH · June 12, 2016, 10:04 PM

Aaarrghh · June 12, 2016, 10:24 PM

Quote from: Rickf1985 on June 12, 2016, 09:47 PM
On the serious side, If you had that much or a squirrel issue you need to go over every inch of the wiring on that RV. You do not want to find the chewed wires as the magic smoke is coming out at 60 MPH on the interstate!

I've done a lot of that, to get the gauges and lights working again. You wouldn't believe the places they got into. They even ate up a foot of both wires on top of the gas tank. I still have vacuum hoses I can't find both ends of. The AC won't run and the cruise doesn't work, 'cause I don't know what wires and tubes go where for the controls. I've examined all the wires behind the dash, thankfully they didn't go there. I doubt the thing in the photo works correctly. I guessed at rewiring that. In most cases I could identify both ends of a chewed wire, but not there. I'm still figuring stuff out - like the EGR valve.

Rickf1985 · June 13, 2016, 08:46 AM

Your best bet is to find a early eighties heavy duty van with a V8 and get the entire wiring harness. It would have to be in better shape than yours. Even a standard van harness would have most everything you need, probably a few extras you don't but they could be cut out.

I remember the days you could go into a junkyard and take that harness out yourself and pay about 25-50 bucks for it. Advantage being you took it out so you know all the connectors and you can keep all the little clips and things that break. And you are going to be a lot more careful taking it out than the yard guy is.

Aaarrghh · June 13, 2016, 02:19 PM

Quote from: Rickf1985 on June 13, 2016, 08:46 AM
Your best bet is to find a early eighties heavy duty van with a V8 and get the entire wiring harness. It would have to be in better shape than yours. Even a standard van harness would have most everything you need, probably a few extras you don't but they could be cut out.

I remember the days you could go into a junkyard and take that harness out yourself and pay about 25-50 bucks for it. Advantage being you took it out so you know all the connectors and you can keep all the little clips and things that break. And you are going to be a lot more careful taking it out than the yard guy is.

New wiring harnesses might have been an option in February 2015 when I got serious about fixing things, but now I'm well along with it. It's been on the road since October, 2000 miles back. I'm not about to start over. Even then, new wiring wouldn't have fixed the chewed hoses. Besides, finding such a van is getting harder. The 2 at Larry's that I've been depending on for parts have been removed, probably crushed.

cook elandan · June 14, 2016, 10:36 AM

Have you done any thing with the carb. Next choice. By the looks it needs replacing or rebuilding. Accelerate pump is probably dry rotted and the will give you some of your issue. Imo.

Aaarrghh · June 16, 2016, 06:33 AM

Quote from: cook elandan on June 14, 2016, 10:36 AM
Have you done any thing with the carb. Next choice. By the looks it needs replacing or rebuilding. Accelerate pump is probably dry rotted and the will give you some of your issue. Imo.

That's an old photo. Yes, carb was rebuilt last year. Except for the hesitation on acceleration, the motor seems to be running very well now. Averaging 11mpg. I'm examining the emissions hoses and little parts, especially the timing advance controls, hoping for the best mpg I can get without scrapping the whole business, which would be a project for the future. Can you tell me anything about the theory of operation of this part of my emissions setup? The 2 hoses from the check valve go to the TVS on the thermostat housing. I just ordered a new TVS from Rockauto. The vacuum advance is new, an OEM replacement, and the distributor cap and rotor are new. The spark plugs look good and the wires don't show corona at night, so I'd guess they are good.