Technical Ford 352 clogged exhaust

So I have discovered a new little wrinkle in my 66 F100. A partially clogged exhaust. Passenger pipe flows just fine, driver's side tho is there, but not strong at the tip. Getting smoke coming from the area of the header/exhaust manifold, especially after shutdown. Any tricks or tips for diagnosing the location of the clog and dealing with same? Removal by me will be challenging due to space and it would have to be on jack stands. It's a fairly new project to me and the maintenance was pretty nonexistent prior to me picking it up. Thanks all!

Sent from my LM-V405 using The H.A.M.B. mobile app

 

Also, I am going over things prior to driving it, so I don't have a lot of road time on it, need new rubber before can go anywhere without fear of a maypop problem.

Sent from my LM-V405 using The H.A.M.B. mobile app

 

Does it have the hear riser in the driver side exhaust?








Bones

 

Do you have any idea what it is clogged with? Rodent nest, rag, potato? Reason that I ask this is if it were a rag or potato it should be near the end of the tailpipe. Rodent nest could be anywhere. What type of mufflers, baffeled or straight through design? ^^^^^^^^^^ that too. You are fast Boneyard.

 

I believe so. Haven't ever messed with one before so wasn't even looking for it. Sadly my shop light is going down for the night but I will double check tomorrow. It it is say stuck closed, that could explain lack of flow. Do you have any tricks to free one up?

Sent from my LM-V405 using The H.A.M.B. mobile app

 

I wish I did. Can't really tell where or what. Hoping Bones hit the nail, but will certainly take all ideas

It'd be a lot nicer if it were just a banana in the tailpipe.....

Sent from my LM-V405 using The H.A.M.B. mobile app

 

Then it would shoot out as it is slippery. What a mess that would be on whatever it hit as it came out.

 

Shoulda seen the look on the kids' face when he started his John Deere tractor and it spit all the mushrooms I put in the exhaust out!

 

If there is a clog in the exhaust system, wouldn’t the exhaust pipe, muffler, etc, be hotter before the clog? Maybe start it up and use a temp gun down to measure temps on the pipes, or muffler?


Sent from my iPhone using The H.A.M.B. mobile app

 

Don't pull the exhaust manifold until all other possibilities have been ruled out. The FE is famous for breaking off manifold bolts if they've been in there for a long time, sometimes even a short time...

 

Years ago, my Dad had a challenge with a pickup that ran great cold, and would get weaker as it warmed up. Turned out that the exhaust tubing was rolled in "layers", and as it got hot a "flap" of sorts would expand out inside the tube and choke it off. Weird thing, but I have seen plate steel delaminate sometimes, too. I think the heat gun idea is a good way to try to narrow down where you need to look.

 

Study the design of the exhaust system front to back for a few minutes. According to the FOR REFERENCE ONLY Ebay add, the stock left manifold on a 66 F100 with a 352 has a heat riser valve.
https://www.ebay.com/i/263619109001...hxIb6c26NfyeKZDaXBcIMH6XLmkyCwTMaAqyHEALw_wcB

There is a fair chance that valve is rusted shut and some PB Blaster or other good rust solvent should help free it up.
If it moves ok now when you reach down and flip the weight, you may not have run the truck long enough to get it hot enough to open up. Heat riser sends exhaust though a passage in the intake to warm up the intake so the fuel atomizes much better when the engine is cold. But on that one and a lot of dualed out rigs, it causes one pipe to lag behind in the both pipes blowing smoke contest.

 

look for this. they look like spacers between the manifold and start of the exhaust pipe and can sometimes get stuck

 

Late to the party! Anthony and Mr48 Chevy are giving you good advise!








Bones

 

Could be heat rizer/ however most stuck ones I seen the heat melted the plate inside of them. I will bet on a collapsed pipe. Your truck didnt have factory dual exhaust. So one side is likely made from that lamanated pipe and its came apart inside. Your best bet take it to a muffler shop. Put it on the lift. Saw the offending pipe off close to the manifold and you can see the heat rizer. If its stuck closed have them torch it out. If not replace the pipe.

 

I had a newer Pontiac come in where I was working for a tune up, way down on power and the exhaust had a whistle to it. With the customer's permission, we dropped the exhaust and right at the part that goes to the exhaust manifold, it had a piece of doubler that came loose and blocked the flow.

 

In the late sixties or early seventies Ford had some trucks with screens near the end of the exhaust pipe. It could have been an aftermarket deal but I don’t think so. After an engine replacement the scale/rust on the inside of the pipe broke loose and plugged the exhaust on a friends truck. Ruined the new engine. You should be able to hear the problem if it’s at the end of the pipe.

 

FORD in the FE era used double wall exhaust pipe,...a pipe inside a pipe. The inside pipe would sometimes collapse causing a SERIOUS restriction.....

 

Chrysler used to have a heat riser lubricant that worked real good. I believe it had a lot of graphite in it which would help keep the shaft from sticking again. At any rate you will probably have to remove it in order to free it up.

 

Lots of good info. I was able to look and can confirm that there IS a heat riser. The valve DOES open but I'm not sure if it does so properly without assistance. There is a screen that was previously mentioned but it appears to be just above the heat riser. I have seen some folks mention setting up a manual control for the riser (much like a manual choke). The thing that seems odd is that not only does it rotate open and closed but it feels like the pin on the engine side has possibly broken as you can move the weight front to back in addition to rotating. Next step is of course to try and manually open to see if that improves the flow.

Sent from my LM-V405 using The H.A.M.B. mobile app

 

Welp, was able to look at the valve. It appears to be opening correctly. Tried manually opening and closing and holding it in either position with vice grips. No change, so that leads me to a pipe blockage. I am a little worried because the screen seems to be slightly disintegrating outside the pipe, so i am thinking that something has made it down past the valve and is blocking prior to the muffler. May not be fixed but narrowing things down. Appreciate everyone's help. Next stop, a mechanic with a lift

Sent from my LM-V405 using The H.A.M.B. mobile app

 

And a temperature gun to pinpoint the area where the blockage is.

 

That sounds familiar.


Sent from my iPhone using The H.A.M.B. mobile app

 

You said it first. I just reminded him.

 

That you did. Next next step is buying a temp gun. Lol

Sent from my LM-V405 using The H.A.M.B. mobile app

 

Does it have catalytic converters? I Googled 1966 F100 catalytic converts and the list was long. If you have one, replace it with a straight pipe or take a tire iron and bust up the insides. Been there, done that.

 

^ converters started in 1975

 

New terminology to me, or maybe a typo? What do you mean by a doubler? . . . Double walled exhaust pipe ? ? ?

 

Exactly. The engine pipe end at the manifold sometimes has an insert in it to give it strength for the bolt-up.